Categories: all aviation Building a Biplane bicycle gadgets misc motorcycle theater

Sun, 26 May 2019

The New-House Contractor Shuffle










Enter, the Contractors













Posted at 23:54 permanent link category: /misc

Tue, 14 May 2019

The Need for Speed

Norbert the Champ has been ailing a bit in the last few months. I've been flying every few weeks, as the weather allows, occasionally letting a whole month pass between flying dates. The problem is, when the engine sits like that for long periods, it gives condensed water a chance to attack the innards and start creating rust.

The accepted remedy for this problem is to fly more often (how convenient!). The idea is that by flying, you warm up the oil, and encourage the water to evaporate out, as well as getting a fresh coat of oil in all the places it's supposed to be. Ideally, you want the oil to be 180-200°F for at least half an hour to get the water out.

Fortunately, I haven't noticed Norbert's ailment in the sense of feeling like anything's wrong as we fly. Rather, I've been noticing that the crankcase breather tube is drooling a bit of oil/water mixture after flights. I'll come back a week or so later, and there's a 2" pool of mocha-colored oil-water emulsion sitting under the engine, almost exactly like it had a little potty training accident.

The plane is equipped with an air-oil separator, which is a little thing the size of a beer can which is supposed to condense the oil out of the crankcase breather tube, and let it drain back to the oil tank, rather than sending it out over the belly of the plane in flight. It seems to work pretty well, but this new pool of oil was worrying.

Did it mean the separator needs to be cleaned? Did it indicate some other problem inside the engine? The oil on the dipstick came out looking like oil (good) and not like mocha foam (which would be bad), so I wasn't sure.

Finally this last weekend, I got a chance to chat with the local mechanic about it, and his recommendation was to go fly the plane a bit to warm up the engine, then do a compression test. This would confirm whether any of the cylinders were leaking more than they should. Previous compression tests (we do one at least every year) have been good, but this one showed that the #4 cylinder was down a little bit. Apparently the ideal number is 79 out of 80, with a full 80/80 indicating a problem, and anything down to about 40/80 being in the acceptable range (this is hard for my perfection-oriented brain to comprehend, but apparently is true).

After the compression test, the A&P mechanic said, "Frankly, what I'd recommend is that you go out and fly for a while at higher power, like a high-power cruise. That'll probably improve this, though even 72/80 is pretty good." This actually aligned well with my thoughts on boiling the water out of the oil, so I set out to see what I could do.

Norbert and I launched into the warm May day (it was over 80°F that day), and I set out to fly it like I basically never do.

The first order of business was not to climb too high. Normally I'm in the "altitude is insurance" game: the higher you are, the more gliding distance you have if anything goes wrong with the engine. However, the air is thicker and hotter down low, so I mentally plotted a course over a set of flat fields through the Snoqualmie Valley.

The next thing was to push the engine faster than normal. I've settled on a fuel-sipping 2200 RPM cruise (2500 is the maximum, or nominally 100% power), which probably represents around 60-65% power. I've been burning about 5.5 gallons per hour at this setting, which seems like a nice level. I have no idea how much fuel we'd actually burn at higher power, but presumably around 8-10 GPH, which is a lot for a 90 HP engine on a plane like this.

So I launched from Harvey and aimed myself southeastwards. It was interesting to see what happened.

I set myself up for about 1700 feet of altitude, which puts me safely over the legal limit, but not so high that I was losing much heat from the ground-level air. I pushed the power until it was just shy of the 2500 RPM redline limit. The plane made a constant shimmy and judder feeling, very light, but enough to communicate to me that it wasn't happy. The louder engine noise combined with increased wind noise to give a sonic edge to the plane's discomfort. We ended up cruising around 105-110 MPH, vs. my normal 85 MPH at 2200 RPM. Gratifyingly, the oil temperature kept rising, finally stabilizing just below the 200°F mark -- I haven't seen over 150° since last summer. Maybe I have been under-working the engine.

I flew most of the way to North Bend, then turned around over Carnation and flew back, circling once over a friend's house, and then looped back around to Harvey Field. I briefly lowered the engine back down to 2200 RPM and let it settle into its happier cruise speed. It was remarkable how much more comfortable the plane felt. Then it was back up to nearly 2500 for the return to Harvey, and an uneventful landing.

In all, just shy of an hour's flight time, almost all of it spent at just shy of full power. Out of curiosity, I checked the fuel left in the tanks -- I'd taken off with around 21 gallons -- and found there were about 14 left. 7 GPH for nearly full throttle. I had expected more, and would probably plan on at least 8 if for any reason I had to fly for any distance at full throttle; part of my hour's flying time included taxiing on the ground. My fuel dipstick measurement technique is fairly crude, and will never be more accurate than within about a gallon or two (gas cans always seem come in frustrating "gallon plus 3 ounces" sizes to accomodate people mixing 2-stroke fuel, making accurate measurement very difficult).

I was able to visit the plane Tuesday night after the flight on Saturday, and found a small puddle of discarded oil, fortunately not as mocha-colored. There is a distinct trace of oil running down the belly, but it's coming from somewhere in the engine compartment rather than from the breather tube.

A very interesting experiment in Going Fast with my pal Norbert. My key takeaway is that I should probably be running the engine harder for its own good health. The slightly increased fuel burn is a fair trade-off for not having to overhaul the engine (a $25,000 proposition) early.

Posted at 22:21 permanent link category: /aviation

Thu, 09 May 2019

The Great House Kerfuffle

As 2018 descended from summer into fall, it became apparent that the living arrangement my partner and I had wasn't working any more. As winter started up, it became clear that it was working poorly enough that I should probably start packing my stuff. It was unfortunate, but these things happen, and better to part on good terms, which we did.

I had built myself a neat little shop at Hogsmeade Hollow (our shared house), though it was a bit on the small side due to lack of real-estate. It had many electrical outlets (one every 3 feet or so), it had lots of light, with skylights and more LED shop lights than you might have thought reasonable. It had a very cool set of swing-out doors, so there was no overhead track, and there was a smaller wicket door in one of the bigger doors. That's where I was building my biplane.

Of course, when it came time to pack up and move out so we could sell the house, the biplane project had to get packed up as well. Even if the new owner could be persuaded to let me keep working there, I wouldn't want to, since it would invariably be a trek to get there from wherever I ended up living -- no way could I afford to live as close in as Hogsmeade Hollow on my own.

So, it all went into storage, and I moved in with some friends who were willing to let me rent their spare room for a few months while I looked for a new house. Not quite living out of a suitcase, but not that far from it, either.

Then commenced the house hunt. For weeks and weeks and weeks I looked at houses. Starting in January, before I'd even moved out yet (which wouldn't be until the end of February), I was looking at houses. There were some... interesting ones, but nothing that really grabbed me.

I saw houses that were in a great location, but too expensive and with no way to have a shop (a full-stop requirement so I could continue building the biplane). I saw houses that had a perfect shop, but the house itself was so dreary that I could never imagine actually wanting to live there. I saw one house near Aurora that had an amazing dream shop that was also plainly illegal and unpermitted, in the zone of rapacious condo developers who would turn in the owner of such a house in roughly 1.3 heartbeats. I saw houses that were a fine combination of house and shop, but far away from where I wanted to be. I saw one house that had clearly been slowly expanded over the decades by an enterprising owner who really didn't know how to design living spaces, so it was a warren of little four foot tall rooms and improbable doors. I would have had anxiety dreams of finding new, weird little rooms for the rest of my life if I'd lived there.

Finally, as spring started to spring, I started to see more promising houses. I had moved out of Hogsmeade Hollow, and was living with my friends, with a 10x25' storage unit packed in a towering cliff to the edge of the door, and I found a house that was genuinely interesting.

It was built in the 90s, and was grey, situated on an odd little square lot deep in the middle of a block, three houses from the road on a private driveway near but not too near Lake City Way. It was the home of some famous session musician, who'd played with the Beatles, and had framed LP covers all over the walls. It had a pretty large 2-car attached garage, and a kind of funky four-bedroom-and-living-room situation upstairs. It was, attractively, about a 5 minute walk from Fred Meyer and some unexpectedly fast buses to downtown.

But. When I thought about it, my approach to this house was, "Well, it checks many of the important boxes on my checklist of Things I Gotta Have in my Next House." It was, simply, acceptable. The price was decent. It had enough rooms for what I wanted to do. It had an acceptable but not great shop space, with potential to be pretty good (but not great). It was, in my mind, a kind of acceptable grey, much like the color of the siding. I totally could have made it work.

That, however, is not a great way to approach a ¾ million dollar investment that should keep me happy for the next 20+ years.

I dithered. I talked to friends and parents and my real estate agents for hours and hours trying to work out if this was a good idea or not. I simply couldn't decide, since my emotional reaction was absent, and my logical reaction was 95% in favor of the place. A noticeable part of me knew it was the wrong choice, but the months of searching had worn me down, and it was ever so tempting to just get it over with, even if it wasn't the perfect house.

Still dithering, and still poring over real-estate listing websites like my life depended on it, I marked out a few more houses that looked like they might be promising, but almost certainly would let me down somehow in person. Agent in tow, we went to look at them, stopping first at the grey house again to see what I thought of it on second inspection. No different, as it happened.

The second house on the list for that Saturday trip was in North Seattle, about 10 blocks north of my previous house on Dayton -- that had been my starter-house, and I'd planned to be there for around 5 years, but ended up staying for 15. This North Seattle house was listed as being a bit over 3000 square feet, and over my maximum price, so I figured it would be a fun lark then we'd move on. 3000 square feet is far too big for just me, though the photos looked pretty good.

I'd taken to bringing along a GoPro style camera that I wore on a forehead harness, so I could record what I was seeing as I walked through all these different houses. They started to blend together something fierce; having a recording of what I'd seen was great for keeping them apart in my head, and occasionally helped me understand some factor I hadn't been paying attention to the first time through. I only made it the length of this North Seattle house before you can clearly hear me say on the video, "You know, I think this is The One."

This house (which I am provisionally calling Brinkley Manor in my head, after the country house of Tom and Dahlia Travers, Bertie's sole good aunt in the P.G. Wodehouse stories of Bertie and Jeeves, which country house is called Brinkley Court -- I think my grandfather would find this funny, if he were around to hear my Wodehouse reference) has a wide front porch with a swinging bench on one side. The front windows contain cut-glass tulips in lead framing, an elegant touch you don't find on modern houses. It has a large living room with a fireplace insert, an unexpectedly open dining room, and a spacious though outdated kitchen with a generous eating nook off the back end. It has four bedrooms, the first of which is on the main floor, and is an odd oversized, elongated shape. Upstairs are three bedrooms and a full second bathroom. And in the back yard, sitting unpretentiously and awaiting my attention, is an oversize 2-car detached garage which is (just barely) wide enough to accept a fully-rigged Marquart Charger biplane, and long enough to (comfortably) accept a fully-rigged Marquart Charger biplane. This house, this provisional Brinkley Manor, has a full basement in which I can stand comfortably upright nearly everywhere. It smells of wooden floors and old-house, an aroma which I find nearly irresistable.

It is, in short, The One.

Of course, it has downsides. The price is the big one -- the listing price was nearly twenty thousand over my maximum price, and had been dropped repeatedly since it was first listed, a discouraging sign. It is possessed of a surprisingly large lot, most of which is covered by lawn, which requires far more care and maintenance than I want to put in. Every single appliance in the place is at least 25 years old, and all appear to be near the end of their lives. It needs a surprising amount of maintenance on the brickwork, which has been let go for too long. It is, frankly, several bedrooms too big for one guy and his biplane project.

However, it only took me about 20 minutes of thinking to realize that I wanted to put an offer in. We called the seller's agent and got the story that there was a previous buyer, but they were first-time buyers and had been utterly freaked out by some heavily-charred floor joists in the basement (properly reinforced and stronger than when the house had been built), presumably in addition to the looming dollar-signs over every appliance and some of the less well-maintained aspects of the house. The price had dropped more than fifty thousand dollars since it first listed, and it had gone pending, then come back on the market. Both of these things are enormous black eyes in the current Seattle housing market. It went on the market in Feburary, in the middle of a giant snowstorm which kept pretty much every potential buyer off the streets and out of open houses, and had been on the market for over a month (another black eye).

All of this added up to the idea that I could offer less than asking price, and be reasonably certain it would be accepted. We actually got Hogsmeade Hollow under similar conditions, with a previous buyer who backed out on the inspection, doing the house a noticeable injury in the market.

We had the previous buyers' inspection report for this Brinkley Manor, and I pored over it carefully: it's a 100 year old house, and had a modest set of 100 year old house problems. Plus it's got a bunch of old appliances that will need to be replaced soon. That's what's wrong with it. All acceptable to me, so we prepared a no-inspection-required offer and submitted it on a Thursday evening. It was countered the next day, within 12 hours: the price was accepted, but the seller (we suspect actually the seller's agent, not the seller himself) required a zero-day inspection period for the title documents.

This still seems a little petty to me, but they stuck to it tenaciously. It seemed to be a reaction to the previous buyers backing out -- they wanted to give me as few outs as possible. The practical effect was that I needed to carefully review the title documents (which should have all been present and available) before saying yes. Presuming I didn't find anything objectionable, we could proceed.

There followed the most stressful weekend I've spent in quite a while. Of course I tried to look over the title documents on Friday evening, and of course one of them was missing. It appeared in the title report as a link, and when I clicked on the link, the resulting page said, "This document has not yet been received from the county." The title report was dated August, 2018, about 6 months beforehand. That document was not going to be arriving from the county. The missing document was the Conditions, Covenants and Restrictions document, arguably the most likely place for Unacceptable Hijinks to appear, so I was very reluctant to just wave my hands and say, "Yeah man, no worries."

But, naturally, the title company was closed for the weekend. My agent pulled some strings, and suddenly in the middle of Saturday, a title report appeared in my inbox for a neighboring lot. Weirdly, the recording number for the document I wanted to see was identical to the one that was missing from the other report. I read it over, and found nothing objectionable (but definitely hilarious: 1. no house worth less than $2000 may be erected on the lot, 2. no barn or other nuisance will be permitted on the lot -- apparently people were moving far from downtown to make little farms in 1921). But it wasn't for my lot, so it didn't really help. There was some back-and-forth about the identical recording number, but that was inconclusive.

I put together some moderately legalistic language for a counter-offer, which basically said, "I'm 100% into this house, but I need 6 hours after receiving the missing title document to make sure it doesn't require me to host a boarding house for evil clowns or something," and we floated it past the seller's agent. No dice.

Then, equally suddenly, on Sunday morning, I received a new title report, dated February 2019, and, hallelujah, it had a working link for the correct CC&R document. Same restrictions. No problem. No clowns. A quick docu-sign session, and suddenly we're under contract. The open house that Sunday was still held, but we presume that anyone who tried to make an offer was told the house was already under contract.

Everything from then on flowed in a pleasantly clockwork-like manner. The loan came through in record time (only about a week), and a few weeks later, I was signing a giant stack of papers asserting that I'd be paying a lot more in rent every month, but I'd have a pretty sweet place to lay my head each night.

On April 24th, 2019, I ditched work early and went to the real-estate office to pick up an improbably bulky envelope full of keys, and take possession of my new house. If I'm very diligent and pay my bills every month, it'll finally be all mine in 2049.

The putative Brinkley Manor; click for gallery

Posted at 00:21 permanent link category: /misc

Sun, 21 Apr 2019

Flying for Passport Stamps

The Washington State Department of Transportation and a bunch of aviation organizations just released the Fly Washington passport program. Basically, it's a program where you get a free "passport" booklet which contains a bunch of blank spots organized by region of the state, and your job is to fly to different airports and fill out the passport. Apparently there's some kind of prize at the end if you fulfill a set of requirements.

The goal of the program is to encourage aviation, and particularly to drive traffic to smaller airports that have been suffering from lack of use in the last decade or two.

I'm here to tell you, I love this kind of thing. I always envied people who had passports full of visa stamps; there's just something so satisfying about all those stamps from all those places. It's not even the places that appeal to me, just the sheer collector-impulse OCD satisfaction of pages covered in stamps. So I fell for the Washington aviation version hook, line and sinker.

Despite what it says on the official page, it appears that most airport offices have at least a handful of passport booklets available. You don't have to go exclusively to the four official places to pick one up. I was able to get one at the Harvey Field FBO office, and they had a stack of at least ten more ready to give away. At least here at the start of the program, it's worth asking at your local airport.

Norbert at the Darrington Airport (1S2)

This weekend was my official entre into the passport stamp game. I managed to hit five different airports over two days -- yesterday I flew up to Lynden to visit a friend, and today I took the afternoon to specifically go out and collect some stamps, eventually stopping at Arlington, Darrington, Paine Field, and Harvey Field. I expect to have more days like this over the summer, where I just go flying for the day and hit new airports I haven't visited recently, simply to collect the stamp.

The thing is, from what I can tell, pilots will grab at nearly any excuse to go flying. It acts nearly like an addiction. "Gotta go collect some stamps" is a ready-made excuse, and seems to me like an excellent way to get a bunch of pilots into the air and visiting airports far and wide across the state.

On today's flight, I started out at Harvey as usual, and grabbed the stamp from the office, where it's temporarily being kept until they set up an external station for it. Then it was off to Arlington for my next stamp -- Lynden was collected yesterday. Arlington was interesting, because the wind changed direction as I was fuelling up, then Norbert's carb heat seemed to malfunction at the run-up check. I pulled back around to a taxiway, shut down, and did a quick visual check -- everything looked right, and on the next run-up it worked like it should. These little Continentals apparently ice up at the slightest provocation, so a malfunctioning carb heat system is a big deal.

From Arlington, I had to ponder where I wanted to go next. Norbert is still limited by a lack of blinkenlights, which keeps it from being legal for night flight, so I had to be back to Harvey before the sun set. That ruled out any longer flights, but as I was looking at the chart, I realized that Darrington was only about 25 nm away, and I'd never been there before. That seemed like an ideal destination, so I launched and turned northeast from Arlington.

The Darrington airport is a very small strip set near downtown Darrington -- Darrington is a town of about 1400 people, so "downtown" is a relative description. Nevertheless, the airstrip is right in the middle of town. I was interested to see runway lights and a beacon: I had flown (in a different plane) out to the Concrete airport a few years ago hoping to watch a meteor shower from a very dark place, but Concrete didn't have runway lights. Darrington isn't quite as dark, but the ability to actually land at night overcomes that downside to some extent.

The wind was blowing pretty strongly from the west, so I set up for runway 28. I actually overestimated the amount of wind the first time around, and wound up too high to land, so I went around and tried again rather than try to salvage an obviously flawed landing approach. Once I got down, I parked the plane next to a helicopter with a massive boom strapped to the skids, which looked like it hooked up to some kind of geological sensor box. The stamp at Darrington is located in a "small box on the beige hangar" -- with the aid of the photo on the passport website, I realized it was what looked like a discarded electrical junction box. I gathered my stamp and took a few photos. I found Darrington to be a surprisingly delightful little airstrip.

The flight back was not as daunting as I'd feared (I was expecting the headwind coming up the valley to really slow me down, but it wasn't bad), and I realized that it was only 7:20, and I had ages until sunset (8:03 pm), so why not pack Paine Field into the flight? I entered my best powered-descent mode, hitting 115 MPH (normal cruise is about 85, so this is screaming for Norbert) as I made tracks for Paine's traffic pattern.

Once on the ground, the Paine ground controller didn't know about the passport stamp, so I stealthlily looked it up while doing a very slow taxi. I called the ground controller back, and after a few minutes of mutual confusion, they got me directed to the right spot, right next to Regal Air. I leapt out of the plane, ran into the flight planning space, stamped my passport, and dashed out again. Norbert was swung 180° and shuddered to life again -- that sun seemed to be accelerating toward the horizon as a cloud bank suddenly hid it from view, and the moment of sunset is my official cutoff.

Fortunately, there was no waiting to get to the runway, and I was off the ground having only spent about 10 minutes between landing and takeoff -- that's definitely a record for me. I managed to touch down at Harvey with nearly 5 minutes to spare, and relaxed with a celebratory snack as I watched the sky fade from blue to pink to purple over Norbert's nose. I had spent a mere 14 minutes between starting the engine at Paine and shutting it down at Harvey.

Flying continues to be a surprisingly potent source of happiness for me. It finally took finding my own airplane to really get into the groove of things, but I'm glad I did. Now I just have to plan out the next few batches of passport stamps I need to go for...

Posted at 22:48 permanent link category: /aviation

Sat, 23 Mar 2019

Crosswinds and Turning Stalls

Image by Chris Kennedy, used under CC BY-NA 2.0 license

I found myself with some free time a couple days ago, and decided to take Norbert the Champ up. There was an occluded front due in the afternoon, so I had to abandon my original plan to fly over to Port Townsend (0S9) for a late lunch. Instead, I decided to do some pattern work and possibly some turning-stall work in the practice area. I wanted to stay close to the field so any nasty weather that turned up wouldn't catch me away from home.

According to the new weather robot at Harvey Field (S43), the wind was blowing about 180-190°, and between 10 and 15 knots in gusts. The closest runway is 15L, so there was a bit of crosswind, but nothing terrible. The gusts made things more interesting, but fine practice for me -- I rarely get to take off and land with crosswinds and need all the practice I can get.

One of the members of my EAA chapter has been developing a pretty cool program aimed at experimental (homebuilt) aircraft, to determine and then correct low-speed stall characteristics. Specifically, he's worried about the base-to-final turn, which is the closest to the ground most pilots will ever turn, and thus the one most fraught with danger should anything go wrong. He recently lost a friend to a likely stall-spin accident on a base-to-final turn, so his idea has received fresh momentum.

Something he mentioned recently was that most pilots haven't explored their aircrafts' stall characteristics except the most basic straight-ahead power-on and power-off stalls. Stalls while turning can be very exciting, easily leading to a spin -- a condition which may be unrecoverable at low altitude, and a prolific killer of pilots in the beginning years of aviation. I realized that not only did I not know my plane's behavior in this condition, I'd never done a single turning stall in my entire flying career.

The setup for these stalls is exactly the same as normal stall practice, except the plane is turning. Add at least another thousand feed of altitude compared to normal stall practice, just in case. A spin can develop very quickly, and the extra space gives you a bit more breathing room to recover if it surprises you. It would be best to have experience recovering from spins and recognizing incipient spins before trying this yourself, but read this handy article on spin recovery at a bare minimum. I spent several hours doing spin recovery training with a CFI a few years ago, which makes me barely competent, but I felt safe enough to give turning stalls a try.

The first thing I tried was power-off turning stalls. I figured, correctly, that with less energy involved, things would be a bit calmer. So I set up for my normal descent to landing -- carb heat on, power to idle, and enter a 20-30° bank to turn from downwind to base. Since I didn't know exactly when the stall might happen, I put myself into a constant rate turn, kept the ball centered with the rudder, and pulled back on the stick. With the hand grip buried in my belly (I really need to get rid of that thing; the belly, not the handgrip) and maintaining a nearly 45° bank angle, the plane simply refused to stall. Just to eliminate the possibility that the 7EC Champ is more resistant to turning stalls to the left than to the right, I climbed back up to 4000 feet and tried again, this time circling to the right. Nope, no stall.

Surprised, I climbed back up to 4000 (the Champ didn't seem to be stalled, but it was definitely going down quickly, losing 700 feet in what felt like maybe 45 seconds) to try power-on turning stalls.

This time, I set up for a fairly unrealistic 45° bank coordinated turn at full power, and held the stick full back until I got a definite stall break. To my complete surprise, with the stall, the plane rolled sharply away from the direction of the turn, trying to roll into an opposite-direction turn and possibly stall/spin (I stopped it before it could develop). I tried in the other direction: same thing. Weird.

I haven't yet figured out the aerodynamics of what might be happening with the power-on turning stall, but I was interested to see that it also seems to happen with the 7AC Champ model in X-Plane. My understanding was that X-Plane treats stalls in a somewhat unrealistic manner, since the aerodynamics get pretty tricky around stalls, and it's hard to simulate them properly. It's cool that the simulator mimics real life in this situation.

My EAA member's idea (I'm not naming him because the program isn't official, and I'm not following it, just inspired by the discussion) with his base-to-final stall/spin reduction, as I mentioned earlier, is that pilots of homebuilt aircraft should explore their planes' stall characteristics, including in a turn, like I did. Once it's determined whether the plane wants to drop a wing in a stall (leading to a spin), apply appropriate anti-stall modifications to the wing, such as vortex generators, stall strips, etc. to correct the behavior. This should lead to a safer and more predictable plane. It's a great idea, and I'm glad he's working on it.

I'm equally glad that I tried out a couple of turning stalls to see what would happen in my plane. The results were very surprising to me, both the fact that the plane didn't want to stall in a turn with the power at idle, and the manner in which it stalled with power on. I may spend some time exploring the power-on stall a bit more, to see if I can figure out what's going on with the airflow that causes the plane to flip around like it does. I'll continue flying well away from the potential danger zones of the stall. I'm glad to learn another bit of knowledge about how my plane behaves.

Posted at 23:00 permanent link category: /aviation

Wed, 26 Dec 2018

Building a Biplane: The Data Edition

Just a short take for this one: I've finally put together a page to display my live buildlog. One of my first tasks for myself before I started building my airplane was to code up a simple system to record my activities in a database. One of the big reasons I wanted to do that was so that I could display that log of activity on a web page. I finally found some free time, and put together that web page last week:

My Marquart Charger Buildlog

It's got data (with more to come, I just haven't had time to code it up yet), and it's got photos. Enjoy!

Posted at 10:58 permanent link category: /charger

Fri, 07 Dec 2018

Building a Biplane: In Which Mistakes are Made

I've been warned repeatedly that I was going to make a bunch of parts, then realize I'd have to completely re-make them due to some small error or flaw I built in without realizing it. So, in a way, I'm better off than I could have been.

Having now completed all 36 drag strips (why 36 when I needed 32? Let's charitably say I was building in my 10% extra and not just mis-remembering), I finally sat down to figure out what was the deal with these drag wires everyone else uses. Good timing, right?

So, I worked out the math. The drag strips are .063" thick and 1/2" wide. The total length of drag strip material is 916", if you add all the plans-specified lengths together. Add another 32" for the 1" doublers that go on the flat end of each strip, another 16" for the 1/2" of length after the flat-end hole, and another 51.2" for the 1.6" length each strip is folded over. This amounts to 1015.2" of strip length. With a cross-section of .0315 square inches, this adds up to about 31.98 cubic inches of 4130. It takes about 3.6 cubic inches of 4130 to make a pound, so the final weight of all this metal is:

8.88 pounds

4130 steel has an annealed yield strength (the strength at which deformations like stretch or bend become a permanent part of the metal) of 52,200 PSI. So one square inch of 4130 will lift 52,200 lbs before it will yield. .0315 square inches of 4130 will lift 1644 lbs if the metal is in the annealed heat-treat condition. This annealed condition is important because it's the weakest state of the metal, and after welding, you can't count on the heat treatment state of the metal around the weld. For normalized 4130, the yield strength is 63,100 PSI.

The turnbuckles, at .06 lbs each, add another 1.92 lbs of weight. We will ignore the weight of the pins, since the alternative wire construction will also use pins (though they'll be shorter, and so will contribute to any weight savings). The turnbuckles are rated for 1600 lbs as their "strength" (I'm not sure if that's working load or yield load or breaking load, but I'll guess it's either yield or working load), so they match nicely with the 1644 lb strength of the drag strips.

Total weight is now: 10.8 pounds for the drag strips. Not bad.

But what about wires?

This is where things got real for me. I checked, and realized that although a 3/16" wire has a smaller cross-section than a drag strip (.0276 in2 instead of .0315 in2), the wires are guaranteed to be normalized. You don't have to weld them, so you don't mess up the heat treatment. This means you get to use the higher 63,100 PSI number, and a 3/16" 4130 wire has a yield strength of 1741 lbs. So... it's stronger and weighs less? What's the downside?

AN665-21R clevis fork rod ends (like you didn't know that already)

There really isn't one. The wires by themselves weigh 8.12 lbs (916" length plus 144" to account for the now-missing turnbuckles, for a total length of 1060"; making 29.26 in3 of steel). You have to add AN665-21 clevis fork rod ends and locknuts, which add up to 1.16 lbs for a total weight of:

9.28 lbs for drag wires.

Hmm. Compared to 10.8, 9.28 sounds pretty good. Saving a pound and a half is nothing to sneeze at -- I've heard tales of people substituting titanium fasteners on a plane for a total savings of less than a pound, at the expense of several thousand dollars. Here, I can do it by returning a thousand dollars worth of turnbuckles and buying $800 worth of rod ends and $200 worth of steel rod. So, I spend the exact same amount of money and save 1.5 lbs? Sign me up!

Now, it would have been really awesome if I'd figured all this out before spending a bunch of hours making drag strips. So, if you're building a Charger, this is my gift to you. Go figure out drag wires rather than wasting a bunch of time on heavier strips. Fortunately, I had a good time with making the strips, and I don't consider it time wasted. I got to meet a local Charger owner to have the strips cut, and learned about fabricating an interesting part. And now I get to play with threading a bunch of 4130 rod and RMA-ing a small army of turnbuckles.

Posted at 21:44 permanent link category: /charger

Mon, 03 Dec 2018

Building a Biplane: The Many Steps to Actually Make a Part

I've been impressed by the seemingly countless steps necessary to actually make a part for this biplane build. I'm currently in the middle of making the drag and anti-drag strips, which will go inside the wings as crossing "wires" to keep the wing structure from racking forward and aft.

At first glance, the drag strip idea makes a lot of sense -- no special tooling required, sheet metal is widely available (and probably more available or cheaper in the late 1960s than 4130 wire of the appropriate size), it's easy to cut on a sufficiently beefy shear, etc. However, on reflection and having accomplished 90% of the construction of the strips, I think I would have been happier buying wires.

Here's what it takes to make a batch of 36 drag strips:

  1. Acquire sheet metal. $80 at Online Metals for a 2x3' sheet of .063" normalized 4130. This was by far the simplest part of the process.

  2. Find someone with a big enough shear to tackle 1/16" 4130. I managed to find someone through the Biplane Forum who offered to do it for free at his shop. We cut my sheet into about 40 1/2" by 36" strips.

  3. Polish the edges of the cut strips. I finally figured out that I could hit multiple strips if I was careful by using the belt sander that has served me so well making ribs. This process alone took over 2 hours between finding the right procedure and actually doing it. I started out with draw filing individual strips clamped in the vise, which doesn't count the 2+ hours I spent making perfectly smooth vise jaw covers. Such a simple operation that took so much time and head-scratching.

  4. Bend the teardrop end of the drag strip (see the above picture). 4130 is no slouch when it comes to the strength department, and I wanted to get these bends perfect the first time. The solution I eventually came up with was to build a bending jig out of beefy 1/4" thick angle iron and 1/4" plate (7.3 hours, not counting driving around hardware stores for a couple hours, looking for 1/4" angle iron). This can be used in the 12-ton el-cheapo hydraulic press I got back in my engine rebuilding days to get the strip most of the way bent, then it's off to the vise with a hunk of 1/4" round to close the end of the loop, but keep the teardrop open.

  5. Weld the edges of the loop's tail. For all my initial fears of welding, this was among the simplest operations in this process. It still took 3 hours to weld all 36 of them.

  6. Cut the slot into the teardrop. This process was the subject of much heartache for me. My first idea was to use my milling machine with a very tiny endmill to cut the slot before the strip was bent. This worked, but was very slow, and ran a substantial risk of breaking the cutter, for it was ever so wee. Then I had the idea to use a slitting saw in the mill once the loop had been bent. Much better, but I discovered that after welding, the slot would expand a bit, and the plans are very particular that the slot should be a particular size. So I thought it better to weld first, then cut the slot to eliminate welding as a possible source of error. I welded up the first 17 strips, and tried to cut the slot in one of them, only to be horrified to find that welding modified the strength of the metal such that the saw (which had worked perfectly before welding) suddenly sounded like it was about to explode. Finally someone on the forum suggested using an abrasive cutoff wheel, which worked well, and was the method I finally used to cut the rest of the strips. I spent nearly 5 hours just figuring out how to cut slots and then slotting all the strips. I'm glad I didn't have to use a hacksaw and file to do the job, as someone suggested when I asked how Ed might have expected the average homebuilder to do it.

  7. Clean up the welding scale. I started out by hitting the strips with sandpaper to clean up the scale, but it didn't do a very good job. I finally switched to a wire brush and had much better success. I also destroyed two partially-used wire brushes in the process. If I have to do any more of that, I'm getting the wire wheel set up on my bench grinder again. I need to do that anyway, as long as I'm welding parts.

That's the process so far. I'm not done yet, but that's as far as I'm taking it until the wings are built, and I can see exactly how long each strip needs to be.

By contrast, the steps necessary to deal with wires would be:

  1. Buy wire. This requires an order from Aircraft Spruce, and costs more than the sheet metal ($128 + shipping vs. $80 for sheet metal).

  2. Cut wire to length. Hacksaw and file to clean up the cut.

  3. Thread ends. Time-consuming, and requires a left-hand threading die for one end, but a well-denfined problem with a well-defined solution.

That's it. If I had it to do over again, the extra $50 would be 100% worth it. I think the turnbuckle situation would be a bit cheaper too, by at least half. If you find yourself building a Marquart Charger, may I humbly suggest that you don't follow the masochistic "Do it exactly per plans" path that I have, at least for this particular situation.

For your edification and edumacation, I also filmed much of the process and turned it into this moderately interesting video:

Posted at 23:06 permanent link category: /charger

Mon, 26 Nov 2018

$50 COOAU 4k Action Camera Review

If you go to Our Favorite Online Retailer that Used to be a River, you will find about a gajillion "action cams." These are little boxy cameras that always come with a hard plastic case so they can be used underwater, and usually fit onto a now-universal two- or three-bladed mount first pioneered by GoPro. They range in price from about $50 for the cheap Chinese knock-offs to many hundreds of dollars for the name-brand versions.

I still own a first-gen GoPro, which was powered by AAA batteries that would inevitably rattle loose about mid-ride when I was filming motorcycle races back in 2008. I don't think it works any more. It was ok, but felt pretty chintzy at the time, and didn't have a screen on the back or any more feedback than a little LCD panel with a number and a couple icons on it. Times have changed.

A few years ago, I got a Xiaomi Yi 4k 2 camera, which was, at the time, a $250 Chinese work-alike of the $400 GoPro Hero 3. It wasn't a cheap Chinese knock-off though, and I've actually been pretty happy with it. Its biggest problem was that the 1/4" tripod mounting screw broke out of the body. The thing it never did that I wanted it to was to take an external audio input.

So, a week or two ago, I typed some appropriate search terms on our retailer's site, to see if I could find an inexpensive camera that would take an external microphone. Sure enough, there were a gajillion of them, priced between $50 and about $150, all with brand names that make your eyes bug out, they're so weird. So of course I chose the $50 kind. Here's part of the description they apparently came up with on their own:

COOAU Sports Camera comes with several powerful function,such us Loop Recording,Time-Lapse Shooting, Car Model, Underwater Model,Slow Motion,Audio Record,Burst Photo, giving you the texperience of a digital camera.Exposure Value and White Balance meet various needs under specific conditions.The F2.5 Lens allows more light to enter the camera to make sure the photo and video are extreme clear under low light conditions

(Text copied and pasted from big online retailer site, can't add enough [sic] tags without making it ridiculous.)

COOAU's motto or saying or subtitle or whatever you want to call it is "MAKE YOU COOL & PROUD". Sure.

What it Comes With

So anyway, it's a $50 camera that includes the camera, the waterproof case, a plethora of mounting widgets, an external microphone (yes!), not one but two little batteries, and a carrying case. This is one of those cases where you wonder how they can afford to sell them for this price. It claims to have a Sony sensor, but I would be surprised to learn it was a recent Sony sensor.

First Impressions

The first impression as I laid my hands on the camera itself was actually pretty good. It's covered in a soft, grippy rubber that feels much higher quality than a $50 action cam has any right to feel. Fortunately, as soon as you check out the buttons or actually turn it on, you're back into reassuring territory. The rear screen turns on at a nearly obnoxious brightness with the bright white COOAU logo splash screen, and a tiny, tinny power-on noise plays through a speaker that must be 2mm across. It cuts off before it's finished, and the screen blacks out, and you think something's wrong. Then the screen lights back up again, and you're looking through the sensor and very wide-angle lens.

The lens itself is quite wide, 170° according to the description. It's described as being fish-eye, which is kind of right. I'd rate it as about half-way to fish-eye, like they were trying for rectilinear, realized it was way too much work, and gave up. It's not bad, it's just kind of its own thing, neither rectilinear nor fish-eye but somewhere inbetween. Initial testing inside the house at night (unlikely to be a cheap action cam's strong suit) was not terribly encouraging, with noticeable grain and poor dynamic range.

The user interface is useable, but a bit on the weird side. It has three buttons across the top: power, M, and a circle. The power button is pretty obvious until it's not; you quickly discover M means Mode; and the circle is the most sensible of the three, being either record or select. The M button switches you from video to still camera, then to video review, then photo review, then settings. Once you're in settings, it keeps looping through until you get to the Exit Settings mode (a U-turn arrow icon), and press record/select; if you press M again, you're back to the first settings screen, which takes some getting used to. The power button, once you're in settings screens, moves the cursor to the next thing. So if you want to set the video mode, you press M until you're on the video settings screen, then press power to move the cursor down until video mode is highlighted. Then you press select to enter the setting, power to move to the option you want, and select to pick it and exit back to the higher level menu -- there is no "back" button, you just gotta select something.

My initial tests with the internal and external microphone suggested that the internal mic is probably made of the same materials that go into a foxhole crystal radio, and very nearly doesn't record sound. The external mic, on the other hand, sounds pretty good, though it peaks quickly, and doesn't seem to offer any kind of gain control.

I was immediately annoyed with the battery cover, a small piece of plastic the size of an elongated postage stamp, which is sure to become lost within a month of owning the camera. I understand that the hinges on other cameras can be problematic, but this completely disconnected battery cover seems like a step in the wrong direction. Fortunately nothing will fall out if the cover goes missing. Along the same lines, the port cover on the other side of the camera is amazing for its ability to snug back down into its ports even when you are explicitly trying to plug a cable into one of them. It has to be actively restrained from getting in the way.

Actually Using It

The reason I got this thing in the first place is to record my melodious voice as I fly around in my little airplane. The first proof-of-concept test was to jam the external mic into the headset's earcup, and use that to record what my ear would hear. For lack of anything better to film, I aimed the COOAU at my ugly mug, while the Yi did its standard duty of aiming out the windshield to show a more-or-less pilot's-eye view.

I mounted the two cameras with a combination of the relatively heavy pro clamp mount I use with the Yi, and the pile of mounting widgets the COOAU came with. Mounting options in my Champ are limited, so the COOAU (facing me) ended up really being a receding-hairline-watch camera rather than a good view of my face. Not the camera's fault.

I fired up the plane, and jammed the mic into my headset. I had no idea what the audio would be like, though in reviewing it, it's at least usable. Unfortunately, keying the radio results in huge distortion (not too surprising), so I will be subtitling the video that will end up at the bottom of this review. Fortunately, this is not a challenge that most users of the COOAU 4k (remember, "Make You Cool & Proud!") will run into.

The flight went as well as I could ask, and as I write this, I am in the midst of exporting videos so that I can edit them together. I've reviewed some of the COOAU footage, and it's actually pretty decent. The dynamic range compression is still there, mostly noticeable as JPEG-artifact blowout on my giant forehead when I lean forward. The finished video will not be color corrected or adjusted in any way other than cuts (you don't want to watch an hour-twenty of me flying around, it's rull boring unless you're actually there), so that you can see exactly what comes out of the camera.

As is common to avoid creating over-large files, the COOAU 4k splits its videos up into 15-minute chunks when recording 1080P at 30 FPS. There's probably a more efficient way to join them together than what I'm doing, but I never claimed to be an expert at editing video.

I'm using Davinci Resolve 15 for my editing (because free, also awesome) on a recent iMac, and one problem cropped up: although the built-in QuickTime Player app would play back the audio on the COOAU clips, Resolve couldn't decode them. They just came across as silence. Many of the questions about the camera on our retailer's site had a canned response from COOAU about making sure audio worked right, and defensive statements about how it's AAC audio, so evidently COOAU is sensitive about this audio issue. I got around it by using the QuickTime Player to export the audio. The resulting m4a file imported well into Resolve, and it was a matter of mere moments to line the audio up with its clip.

I had the COOAU mounted upside-down, and forgot to set the "upside-down" setting. As a result, I had to flip the videos in Resolve, which is fortunately a trivial operation. The Yi automatically detects when it's upside-down, a feature that I have appreciated, and appreciate even more now.

One thing to note is that the batteries can only be charged in the camera. Charging from nearly-empty takes an hour or two on a normal USB port. One battery lasted me for an hour and seventeen minutes of recording, though it showed no bars left when I shut it down. It appears to work fine when plugged into an external power source, so vehicle use will only be limited by storage space, and it does include a "loop" mode that only records the last N minutes of footage.

My camera came with a card in the package saying I'd receive a free battery if I left an "honest review" on our retail site and told them about it, which I'll probably do for yuks, because free stuff.


Reviewing the footage from the Yi and the COOAU, there's no question that the Yi looks nicer. Does it look five times nicer? Not really. The footage from the COOAU is pretty good. I can't really compare the internal microphones, as I haven't played with the COOAU's mic.

The Yi uses a touchscreen for most of its settings, which offers an interesting comparison: since the COOAU is not a touchscreen, you can do all the setting and adjusting you want with the camera while it's in the watertight case. That's not true with the Yi. Score one for COOAU (Cool & Proud!).

Is the COOAU worth fifty bucks? No question. I'd actually say it's a pretty good deal for $50. Not only do you get a halfway decent action cam, you get a bunch of mounting widgets and a pretty good carrying case. If you're coming from a GoPro or Garmin or Sony or similar high-end camera, you'll probably be disappointed in the quality, but that's kind of not the point. It's a fifty dollar camera. I could strap it to my wing, and if it departed the plane, I'd be considerably more worried that it would damage something when it landed than that I'd lost the camera. It's a perfect "disposable" camera if you need an action cam for something dangerous enough that you'd hesitate to put your $500 GoPro in that situation. It would be a fantastic My First Action Cam for a young person to strap to a helmet or handlebars or snorkel mask.

It even records external audio with a perfectly standard 2.5mm mono phono plug, no weird, hard-to-find adapters needed. I'll probably look for a smaller microphone if I want to keep using it inside the headset, the supplied mic is a fairly chunky 12mm in diameter.

In all, I'd say it's a good deal on an acceptable camera. This is not the camera to get if you want to include your footage in your high-class indie film (unless low-quality footage is the gimmick). It is absolutely the camera to strap to your amateur rocket to get a cool shot you'd hate to try with a higher value camera.

Coming Soon

This review is not finished. I'll be taking some photos and possibly more video to show some of the idiosyncracies of the camera. Check back in a few days.

Posted at 09:47 permanent link category: /gadgets

Thu, 13 Sep 2018

A Triumvirate of Chargers

My work sent me on a trip to Orlando recently, and I checked in with folks on the Biplane Forum to see if there was anyone who's be interested in showing off a project, or if there was some aviatory attraction I should definitely see. I got a few suggestions, but by far the most appealing one was to visit a set of three Chargers at the Ormond Beach (OMN) airport.

My work duties were finished around 5 on the day of my visit, and I was rolling by about 5:20. Unfortunately, from where I was, it would be at least an hour and a half drive, and traffic at 5:20 on a weekday meant there was an additional ten minutes of delay. Silently cursing as I passed through Florida's plethora of poorly-explained road toll booths, I made it to the airport around 7.

I met D., who had made the invitation initially, at the gate, and he introduced me to a crowd of folks, all of whose names have already disappeared from my fickle memory. I think two of them were Charger owners, D. used to own a Charger, and there was one owner who wasn't at this particular event. They were gathering anyway for a birthday celebration for R., who I ended up talking to after my flight.

D. looked up at the sky and said, "Let's get you up before sunset!" We pulled his plane out, and climbed in. I found that I mostly fit in the front cockpit, but the rudder pedals were uncomfortably close. I still managed to fly the plane just fine, but I wouldn't enjoy a long cross-country in the passenger seat.

I had an airspeed indicator, an altimeter, and a tachometer as my instruments; a control stick, rudder pedals, and throttle as my controls. We taxiied out to runway 8, and after a brief run-up, launched into the humid, warm air. D. gave me the plane as soon as we were out of the traffic pattern around OMN, and told me to stay around 1000 feet to keep under the Daytona Class C, and then we could climb once we hit a particular body of water.

We got to our mark, and I sent the throttle forward. The plane didn't scream upward, but it climbed with more vigor than Norbert the Champ would have. Looking out over the short twin wings was a little strange -- Norbert's wings are 5 feet longer in each direction, and there's only the one on top.

I was more relaxed than I had been in the other Charger I've flown in, probably because I was over the first-time jitters. I found that the plane responded quickly to control inputs, and felt like it was shorter in all dimensions than the comparatively pokey Champ, which is true. Ailerons rolled the wings faster, the rudder swung the tail more aggressively, and the elevator pointed the plane up and down with greater speed and less pressure. It also struck home how much more comfortable the stick arrangement is in the Charger: in the Champ, the stick pivots below the floor, and although this is very neat and trim looking, it means the stick swings pretty far in all directions. The Charger has the stick's pivot above the floor, so you can see the workings of the system.

I tried a variety of maneuvers, dancing around the puffy clouds that dotted the sky: a power-off stall, a power-on stall, steep turns, a slip, a dive, etc. The power-off stall was almost shocking in how gentle it was. It wasn't properly a stall at all -- we were clearly going down while aiming up (or at least level), but there was no break, and I had a sense that at least one of the wings was still flying. The power-on stall was much more interesting, breaking distinctly and dropping the left wing promptly. A release of pressure and a touch of rudder straightened the plane back up, and we were flying again. The steep turn was unremarkable and quick. The slip was pretty weird: unlike the Champ, which seems to be designed to slip, the Charger wouldn't plunge over at 45° and drop like a rock. I could get it over about 20° then ran out of rudder, and it didn't seem to go down appreciably faster than just slowing the motor down and coasting downward. I suppose the advantage would still be that you could descent without gaining extra airspeed, but a slip was definitely where the Champ is the more capable plane.

The wind in the cockpit was basically unnoticeable. It was there, and in cold air I would have been cold, but it wasn't howling through or anything. The windshields were a single sheet of (probably) polycarbonate that had been scored through about half of its thickness by a 1/8" or so saw blade, then bent along those scores to form the three-faceted windshield shape I like for these planes. It was an interesting technique that I haven't seen before. It's nice in that it doesn't leave a big distorted section around the bends, and it doesn't require a frame. D. said that the wind in the back cockpit was more present, but not terrible. He was able to turn off the push-to-talk feature of the intercom, and just leave it always-on, so maybe I block the wind more effectively than other passengers. D. said that a front pit cover is a very good idea, and very nice to fly with compared to an uncovered but unoccupied front cockpit.

As the sun descended toward the horizon, we turned back to the airport, and dropped down to get under the Class C again. D. seemed to be offering to let me land the plane, but as we approached OMN, I gave it back to him, unsure which runway we were landing on, and certainly having no experience landing a biplane. In the traffic pattern is a bad time to learn much of anything, and I figured it would be safer all around to give that particular offer a thanks-but-no-thanks this time.

After we were down -- the landing was stiff-legged but not bad, and I could feel the difference between the Champ's oleo gear and the Charger's rubber donut setup -- we taxiied back in, and I had a chance to wander around the assorted Chargers in the hangar. One was missing its motor (I took advantage of the opportunity to photograph the firewall, motor mount, and what accessories were still mounted), and the other was fitted out with a giant Dynon glass-panel screen in the pilot's cockpit, with a very professional-looking black instrument panel. All three Chargers were painted the same scheme of white and red and black checkerboards and sunbursts. It's a good looking scheme, though it looks like it would take a long time to mask off and paint.

I ended the evening talking to R., who built one of the Chargers (I think he built the one that was sitting with its engine removed, but I'm not so sure now). He was the owner of the one D. took me up in, and I got the impression he's been building airplanes for a long time now. We talked about good and bad points of the Charger design. He pointed out a few things that I should address:

I wish I had had more time to chat with him, but I knew I still had a 90 minute drive ahead of me, and my sleep schedule has been all kinds of messed up lately with the switch from Pacific time to Eastern time plus not sleeping well in the hotel bed. It was after 9 by the time I left, though fortunately the return trip was through much less traffic than the way there. It still took an hour and forty-five minutes to get to the hotel after a stop for gas and slowing down for some torrential rainstorms that passed through.

It was a surprisingly nice visit -- I don't mean that I had expected it to go poorly, just that I didn't have any real expectations beyond that I would see some planes. Everyone was very friendly, and welcomed me as if I've been hanging out with them for years. D. and R. were very generous with their plane and their time, and it was a very kind gesture on D.'s part to let me fly basically the whole flight after takeoff.

I know a few more things to look out for on my build, and I have re-confirmed that the Charger is a nice plane to fly. Being in the 160 HP plane rather than one of the 180 HP planes means I also have a reasonable expectation for how my plane might perform (I'm not planning on using the larger 180 HP motor unless a too-good-to-ignore deal shows up). R. and I exchanged eyebrow waggles and appreciative discussion of putting a radial engine (probably the Verner Scarlett 9S in my case) on a biplane, which would be a 150 HP solution.

So, hooray for unexpected business trips that can be turned to biplanely purposes. I have more information, and another half hour of Charger time in my logbook.

Posted at 10:58 permanent link category: /aviation

Sun, 09 Sep 2018

Flying East

I recently took a day off work, and decided that I would fly Norbert, my little Champ 7EC, to Yakima. Actually, I decided to fly to Wenatchee, but the runway was closed, so I changed my destination to Yakima. The main reasoning was to try flying over the Cascade mountains, which have formed a real barrier in my mind that was limiting where I thought was a good destination.

The Cascade mountains run north-to-south, east of Seattle, and they form an unbroken chain from British Columbia all the way into Oregon, where they merge and blend with a few other mountain ranges. They're not the 11,000 foot monsters to be found further east in the Rockies, but with many of the peaks topping off between 6,000 and 10,000 feet, they're still nothing to sneeze at.

And they have formed the eastern border of where I was willing to fly in the Champ, which is many fine things, but "fast climber" is not among them.

So, I drove out to the airport, sailing past the grinding traffic heading the other direction, toward Seattle. I arrived at Harvey Field (S43) around 10:15, and preflighted the plane. Plenty of fuel, having tanked up at Arlington's (AWO) relatively cheap pump a few days before. Relatively cheap these days is $5.06 per gallon of 100LL gasoline.

I was floating off the runway around 10:50, a bit later than I'd planned, but not catastrophically so. The path I'd plotted out took me down the Snoqualmie Valley to Fall City, where I would form up over I-90, and fly more or less over the freeway to ensure I'd avoid any dead-end canyons. Once to Ellensburg, turn left for Wenatchee (EAT), with a right turn to Yakima (YKM) presenting a good alternative.

The flight briefer had mentioned that runway 12-30 at Wenatchee was closed, but I didn't take much note of it. The airport symbol at Wenatchee shows two runways, so I figured I'd just land on the one that wasn't closed. I've gotten into the habit of just glancing over the airport information for my destination before I depart, now that accessing the chart and supplement with airport data is so easy on the tablet I usually fly with.

As I was climbing out from Harvey, I called into Seattle Radio and opened my flight plan, also giving them a quickie pilot report about the smoke in the air -- I guessed I could see about 50 miles in haze. The flight service operator repeated the warning about runway 12-30 in Wenatchee being closed, which I thought was odd, but I thanked him and switched back to Seattle Approach to set up flight following (a radar service where they call out traffic they think might conflict with your flight path, and very handy). Fall City's tiny private airstrip passed underneath, and I eyed my chart to make sure I wasn't climbing into the tightly controlled Class B airspace that surrounds SeaTac airport (SEA) even as far east as Snoqualmie.

The fact that the flight services guy had mentioned Wenatchee's 12-30 closure again nagged at me, so I pulled up the airport info for EAT. Oh. There is only one runway at Wenatchee. And it was closed. The second runway shown on the chart is present, and thus visually important enough to depict on the chart, but you're not allowed to land on it. Sigh.

So, I called Seattle Radio again, and amended the flight plan to land in Yakima instead. I had considered Yakima as a destination already, so it wasn't any real mental effort to shift my plans.

By this time, I was nearly to my desired 7500 foot cruising altitude, chosen so that I'd be above the majority of the mountain peaks by a comfortable margin, but not so high that I'd climb into the unfavorable winds predicted at 9000 feet. As it was, I seemed to have no wind at all to contend with, which was nice. The air was smooth, and I placidly watched I-90 wind around under me. Snoqualmie Pass crept slowly past (I was making all of 83 MPH over the ground), looking odd and barren with its ski slopes covered in yellowed grass and empty parking lots presenting appealing emergency landing strips should the engine falter.

Then Norbert and I were on the dry side. The road, I knew from driving it in the past, started sloping down, and the vegetation changed. The big lake just east of Snoqualmie Pass passed by, and the last threat of the mountains faded away. In truth, I never felt like I was flying through mountains, since I'd reached 7500 feet by the time I got over serious mountains, and none of the nearby peaks reached that high. There was probably a 50 mile stretch where finding a good landing spot would have been tough, but never impossible.

Then we were on to the valley that spills to the east from Snoqualmie Pass. I flew over the small airstrips that dot the landscape alongside I-90, spotting some, and unable to see others. De Vere (2W1) in particular evaded my efforts to spot it despite knowing exactly where it should have been. Ellensburg (ELN) was easy to spot, and once I reached it I turned right over the hills to find Yakima.

The advantage of having a flight planned out on the tablet is that you get immediate feedback that you're going where you intended to go. Because it's tracking your travel over the ground, corrections for wind drift are built in by the nature of the beast. I could have planned everything beforehand, and filled out one of the cross-country planning sheets I got when I started flying (and before tablet computers beyond the Apple Newton existed), but it would have meant that when I realized I needed to go to Yakima instead of Wenatchee, I would have had to pull out the chart and do some plotting and calculating to know what compass heading to fly. With the tablet, I just scrolled over to the Route tab, deleted EAT, and added YKM. New line drawn on the chart for me, and I'm good to go. I appreciate knowing how to do it the old way, but the new way is pretty awesome.

It was a short leg to Yakima, and Chinook Approach put me in contact with the tower when I was about 12 miles out from the airport. I could see where I thought it should be, but I knew from past experience that I can very easily get airport identification wrong, so I held off on descending until I was 100% sure I had the airport in sight.

Then, being 4000 feet too high, I had a lot of altitude to lose in a hurry. Fortunately, the Champ is a champ at going down quickly and safely, so I put it into a slip, and flew the plane sideways. We descended over Yakima quickly. I realized at some point that I was smelling gas, which is never a good feeling, and glanced out the side window to see fuel dripping out of the right-wing tank vent. Oops. Straightened out the plane, and thanked past-me for filling the tanks full enough that I wouldn't have any danger of fuel starvation, but also slightly cursed past-me for filling the tanks so full I couldn't slip down to get to pattern altitude.

The tower cleared me for landing, and I touched down on the soverign soil of Yakima International Airport.

I knew from my preflight studies that Yakima didn't hold any appealing attractions for me, which is part of why I'd picked Wenatchee at first. So, I wandered around a little bit, looking for an entrance into the terminal to use the bathroom, eventually being directed to the big, obvious RAMP EXIT sign over a gate far from the terminal. Logical, really, that you'd walk away from the bathroom to get to the bathroom.

Having successfully used Yakima as my biological dumping ground, I checked the weather and the fuel price at Ellensburg, and got the plane back in the air. My plan now was to fly the half hour to Ellensburg and fuel up there for the return trip to Snohomish.

The return trip over Yakima town and the ridge to Ellensburg was uneventful, though I did look down at the smooth, bare ridge and ponder a YouTube video recently pointed out to me of a Kitfox pilot landing on similar hills in Nevada. I didn't ponder it very hard, since the Champ is not a Kitfox, and my little tires are not the giant tundra tires he was sporting, and I had no idea if the land below me was public-use or privately owned. Ellensburg hove into view, and I descended down to the traffic pattern, slotting in behind a twin that was doing touch-and-goes.

After a little musical-chairs action with another pilot who was sitting in front of the fuel pump looking at a phone, I pumped another 10 gallons into Norbert's tanks, and made my way back into the air. I was getting anxious about getting back to Harvey, since I was due to meet with an instructor at 4 to do my Biennial Flight Review.

Oddly, I immediately spotted the wind turbine farm west of Ellensburg as I took off, but completely missed it on the way in. It's a huge, distinctive landmark, and I thought it was odd that I hadn't seen it. It ended up being a useful landmark as well, as I communicated with a plane that was doing maneuvers over it, and we were able to negotiate who would go where by references to it.

Past the wind farm, I started to notice that I was flying the plane a bit oddly. I kept adding way too much right rudder. Norbert normally needs a few pounds of pressure on the right rudder in cruise flight, for whatever reason. So it's a habit to just keep that pressure in, but for some reason, I kept adding way too much, so we ended up flying a bit sideways. I eventually decided it had to be from the quartering tailwind that was speeding me along a little bit, but also causing me to drift to the right over the landscape. Even being conscious of it, I found that I had to repeatedly correct my over-use of the right rudder. Fortunately, the side-wind went away about half-way along the mountains, and I was able to stop worrying about it. Snoqualmie Pass drifted by dreamily and I kept glancing at the Estimated Time of Arrival box on the tablet's display. I was going to be 10 minutes early according to the box, but I knew that maneuvering for traffic patterns and taxiing would eat much if not all of that time.

In light of the comparative rush, I decided to do something unusual. I turned right at Snoqualmie Pass, directing my path of travel right over a tall mountain, but with I-90 and the flat fields beyond the mountain still in gliding range. I had been cruising at 8500 feet (if you're flying east, you fly at odd thousands-plus-five-hundred-feet, and if you're flying west, you fly at evens), and tried pointing the airplane downhill without substantially reducing power. This is unusual, but not wrong necessarily. The plane doesn't seem to enjoy flying much over 100 MPH, but the official Never Exceed speed is actually 135 MPH, so there's a lot of leeway available. Being a 60+ year old plane, I don't like to push it to the point of discomfort, but I figured it couldn't hurt to try. Norbert dove like an expert as I put us into a 115 MPH speed-descent. Of course this all had the advantage of getting me to Harvey Field noticeably faster than my normal 80 MPH cruise speed.

I made it on time almost to the minute, shutting down the engine at 3:59. It's funny how these timings seem to work out. My instructor ended up being a few minutes late in any case, and we had a good BFR, he passing me with flying colors. It helps to have an instructor who's just as finicky as you are.

Interestingly, I am writing this entry from 22,000 feet above eastbound I-90, where was just able to observe the same path that I flew a few days ago, but at several times the altitude, and many times the speed. My two-hour flight to Yakima probably would have taken 25 minutes in an Airbus A320. I prefer the two-hour version in the Little Champ that Could, even if it does shiver uncomfortably when you push past 100 MPH.

Posted at 10:50 permanent link category: /aviation

Thu, 06 Sep 2018

Heard on the Radio

I was flying to Yakima yesterday, talking to Seattle Center, an air-traffic control facility that covers most of the northwest United States. Seattle Center is responsible for the airspace that's not around big airports; you talk to Seattle Approach when you're coming in to SeaTac, you talk to Portland Approach when you're coming in to Portland International, etc., and you talk to Seattle Center once you're outside of Approach's airspace.

As a small plane flying under Visual rules (the big planes are all flying under much more restrictive and communication-required Instrument rules), I talk to ATC mostly so they know where I am in case of potential conflicts, and for the reassurance that someone is paying attention to me if anything goes wrong.

Normally, on the radio with Center, it's all business all the time. You get a lot of exchanges like this, where this is the entire conversation:

Controller: United 123, turn left heading zero-five-zero.

United 123: Left to zero-five-zero, United 123.

It's normal to get a long string of these instructions, so you get used to the rhythm of the language.

Controller: Alaska 234, climb and maintain fifteen thousand, one-five thousand.

Alaska 234: Climb to fifteen, one-five, Alaska 234.

Controller: UPS 987 heavy, turn left heading one-two-zero for traffic.

UPS 987 heavy: Roger, left turn to one-twenty, UPS 987 heavy.

Controller: Cessna 456-Tango, contact Seattle Approach, one-one-niner point two. Good day.

Cessna 456T: Nineteen-two for 456-Tango, good day.

Airplanes are handed off to different controllers by zone, so when you cross from one zone into another, you get passed off to that zone's controller. When you switch frequencies, you check in with the new controller, so they know you're on frequency and talking to them:

Cessna 456T: Seattle Approach, Cessna 456-Tango with you, ten-thousand-five-hundred, VFR.

Controller: Cessna 456-Tango, roger.

So when something unusual happens, it sticks out just because it disrupts the flow. Thus the following incident, which happened more or less like this (details changed because I can't remember them), sticks in my memory:

Santos 123: Seattle Center, Santos 123 with you, ten-thousand.

Controller: Aircraft calling Center, say again the callsign?

Santos 123: It's Santos 123, that's Spanish for "underpaid."

Unexpectedly long pause

Controller: [barely contained laughter] Ok, Santos 123, maintain ten-thousand, expect lower in one-zero miles.

I suspect, unfortunately, that you had to be there, but it was a good joke.

Posted at 10:55 permanent link category: /aviation

Sun, 19 Aug 2018

Building a Biplane: Good to the Last Rib

That's a lotta ribs

I reached a pleasant milestone at the end of July: I finished all the ribs for the Charger. I had run out of materials at the start of May, having underestimated capstrip and 1/16" plywood by about 5%. Aside from kicking myself for the mistake, there wasn't a lot I could do, so I went off and did other things while I waited for my order of new materials to ship. I took advantage of the announcement of the new steel and aluminum tariffs to order my fuselage steel at the same time, although that delayed the order by another month or so. What's a month on a 10-20 year project, right? (Sigh)

In any case, on the 22nd of July, I glued together my final two ribs. This is the first major-ish milestone I've reached in the build. It was great to achieve it, but it was distressing how long it took -- more than a year from first rib to final rib. I had known it would take a while, but I was figuring 6 months. I blew my time estimate by 100%.

The downside to reaching this milestone is that I was now without a singular task to work on. When I was building ribs, it was easy to go out to the garage, and pick up wherever I left off on the ribs, going until I was at an obvious stopping place. Now, I suddenly had a variety of tasks to accomplish: profile the spars; machine bushings for compression tubes; weld bushings to compression tubes; produce drag strip.

Profiling the spars is the scariest task for me. Each spar costs between $100 and $150 to replace, but much more importantly, would take something like 6 months to arrive once ordered. Spar-grade spruce is hard to find. I mean, it's easy to order, but Aircraft Spruce and Specialty, despite their name, don't have a pile of spruce sitting around ready to ship. So, if I mess up a spar, that's 6 months of waiting, and about $300 lost (because they're 10-11 feet long, the spars have to ship by truck, which is a minimum of $150 on top of just buying the wood).

Because of this trepidation, I've been dithering. I got a couple of 2x6s at the hardware store, and crudely resawed them to 1" thick to mimic the spar blanks. I tried a variety of methods of cutting them down until I found a method I like: cut the bevels on the edges with a table saw, but cut it oversize, then finish with a hand-powered bench plane. I got a bigger plane (a Stanley #5), but discovered that Stanley has gone substantially downhill in the quality department, and then went on a week-long research bender getting deeply, deeply nerdy about bench planes. I ended up ordering a Lie-Nielsen #5, and have a bid out on a vintage Stanley #7. For those of my loyal readers (ie, all of you) who don't know planes that well, the Lie-Nielsen is the ridiculous-but-worth-it Cadillac of bench planes, and a vintage Stanley is the they-made-them-well-back-in-the-day winner. A #5 is a good all-around size, and a #7 is a bit of a monster, but good for making sure you don't accidentally introduce some hills-n-valleys on your piece of wood.

That's a lotta tubes

I also found myself dithering on the welding front. Although I now have much of the metal in stock (plus some) that I should need, I've been worried that my welding skills aren't up to scratch. I welded up practice piece after practice piece, but they didn't quite seem good enough. Finally, a couple nights ago, I made some new test pieces, and took a methodical approach to solving the problem, setting up the best jigging system I could think of. I welded my four test pieces, and by the fourth I was actually feeling pretty good. Not great, but good enough that I was willing to try with the expensive aircraft steel.

Fortunately, it looks like I had the technique right, and the resulting welds have met with approval from the experienced folks who've seen them. I now have twelve half-compression tubes. Only 24 to go. (Actually, they went really fast. I should have the compression tubes done in a couple of work sessions if I can maintain that rate.) Not quite worthy of the name "milestone," but it was good to get some real aircraft welding done.

I also made my first foray into the world of waterjet contractors. My original plan was to draw up all the little metal brackets and bits that I would need in CAD, and ship the drawings off to a waterjet shop to have the pieces cut. Then all I would have to do was bend the pieces appropriately (easier said than done, but new pieces would be as far away as the waterjet shop when I messed up), and voila! All done. It turned out that I found a good deal on a set of Ken Brock wing fittings, which took care of 90% of my waterjet work for 1/3 the likely cost, and that was an easy decision when it came up on Ebay. However, it didn't include the drag strips (criss-crossed strips of steel inside the wing, which stiffen it and make it so it won't rack side to side), so I've sent those DXF files out to a bunch of shops to get estimates. I'll be curious to see what they say. Of course, the drag strips would have been cut on a metal shear back in Ed Marquart's day, and I need to explore that option as well, since it may be substantially cheaper. I can cut my own slots and holes if it saves hundreds of dollars.

It's nice to be making progress. I wish I was making progress faster, but I need to let go of any concept of building to a schedule unless I want to upend my life to do it. I enjoy still having relationships and friends and other activities, though, so the airplane building will continue to be a "when I have time" priority.

Posted at 18:42 permanent link category: /charger

Thu, 05 Jul 2018

Fuel Used vs. Airspeed (X-Plane edition)

I've been curious for a while to see what the efficiency of the Champ was. How much does engine power buy you speed? What's the most efficient use of fuel vs. travel time?

I don't have a complete answer by any means, but I've collected one form of data:

Fuel flow (GPH) Airspeed (MPH) Miles per gallon
7.4 106.5 14.4
5.77 98.8 17.1
4.1 90.5 22.0
3.53 82.2 23.3
3.1 69.2 22.3

This data was generated in the X-Plane simulator flying a mostly-accurate Aeronca 7AC model someone made available on the download site. To gather it, I flew at different throttle settings, stabilized the plane so it was flying level, and recorded fuel flow and indicated airspeed. Much easier to do this in the simulator than in real life -- I don't have a fuel-flow meter in real life!

Obviously, this is not Hard Science™. It's still interesting. I only gathered 5 data point over the course of about 15 minutes of flying, but it's representative of the range of speeds you might reasonably fly a Champ. The fuel flow numbers are at least similar to what I would expect in reality, though the RPM indicated for a given fuel flow is substantially high compared to what I see in my own plane.

The Champ instrument panel in X-Plane

The conclusion that I see here is obvious: if you're flying a digital Champ in X-Plane, and you have the same model of 7AC I downloaded, aiming for a cruise of about 83 MPH will get you the best fuel efficiency. Pretty much squares with what I see in the real world.

It'd be neat to some day instrument the plane to duplicate this test in real-world conditions, though I doubt I will. Fuel flow meters are expensive, and somewhat counter to the feel of the Champ. If I could do it temporarily, though, that would be very interesting...

Posted at 23:04 permanent link category: /aviation

Wed, 13 Jun 2018

The World's Silliest Commute

Back in February of last year, I got a plane. Norbert, the Champ. I was (and still am) an active member of Chapter 84 of the EAA. EAA 84 has their chapter meetings on the second Tuesday of every month. Now that I owned a plane, I really wanted to fly it to one of these meetings.

The problem is, Chapter 84 meets in Snohomish, at Harvey Field (S43), the same airport where the plane is based. It doesn't make much sense to fly the plane to its own airport. How would that even work?

It works if you're a bit crazy. Crazy like a crazy person!

It goes something like this: very early in the morning, drive up to Snohomish, conveniently going the opposite direction from all the traffic. Get in the plane, and fly it from Snohomish to Boeing Field, which is reasonably close to downtown Seattle, where I work. Take a taxi (since there is no practical bus service) to downtown. Work for the day. Leave a touch earlier than normal, and take a taxi back to the airport. Fly from Boeing Field to Harvey Field, waving slightly ironically at all the poor car commuters below me on I-5, moving through a 10 MPH continuous traffic jam. Go to the meeting. Drive home. Simple, right?

As simple as it should be, the Seattle weather and my schedule have conspired for well over a year to prevent it from happening. If I can go to the meeting, the weather is terrible. If the weather is gorgeous, I'm otherwise committed. Most vexing.

Finally, yesterday, I was able to pull off the World's Silliest Commute™. The weather was predicted to be perfectly flyable until midnight, well after I needed to fly.

I should note that I live about 6 miles from my workplace. A bike trip takes 35 minutes each way. Taking the bus takes 35-45 minutes depending on traffic.

Getting There

So, I left the house at 7 am almost on the dot. I arrived at Harvey Field without much incident 45 minutes later. There was a car fire that was out at Northgate, which slowed everyone down so they could rubberneck at the flashing lights, but that only added a minute or two to the trip. So far so good. I preflighted the plane, and was in the air by about 8:20. I shut down at Boeing Field half an hour later, at 8:49. So far, so good!

The weather was gorgeous for the flight in

I parked the plane at Kenmore Aero Services, who charged me the princely sum of $15 in "handling" to stay there for the day. Cheapest parking on the field, though, and compare that to a day of parking your car anywhere near downtown ($30+). Parking for airplanes is weird.

Anyway, I called a cab, who showed up about 9:05, and we were on our way. Unfortunately, Airport Way (the most logical path to downtown) was blocked, and we had to backtrack and take a very crowded I-5 to get there. I arrived at the office around 9:40. Fortunately my workplace is very chill about when people show up.

So, trip to work: two hours and 40 minutes. Pretty clever, eh!? Also, $15 parking, and $40 for the taxi. Also, 27 driving miles and 24 flying miles.

My plane-a-day calendar was, happily, an Aeronca Champ!

The trip back was even better.

Getting Back

The taxi ride was about twice the cost I'd been anticipating, so I was somewhat anxious to avoid having to take a taxi back. Spending another $40 wouldn't kill me, but it wasn't very appealing either. I've never signed up for Uber or Lyft, so I figured I'd check out taking a bus to close by, and then using one of the rental bikes that litter the city to make the final stretch. The buses run to the north end of the field, but then they divert down the west side, and I needed to go to the east side, which would be a long walk from the nearest stop.

I identified the route: Metro 124 goes right past, and was the obvious choice. I tried signing up for Limebike (one of the rental bike outfits), and was dismayed by the terms I ran into: the Lime app won't even show you the map unless you've got location (GPS) turned on -- which I don't normally do, since I try to limit data leakage. It appeared from the non-existent documentation (ie, how the app behaved) that I would have to load a minimum of $10 into my account, but I have no plans to use these bikes long-term. Overall, the experience left me very unhappy with how it worked, and kind of turned off from the whole idea.

I looked back at the bus route, and realized that A) I needed to go to nearly the southern extremity of the field, and B) there was a bus stop on the west side of the south end of the field. It would only be about a 20 minute walk from the bus stop to Kenmore, vs. the 45 minute walk from the north end of the field (Boeing Field's long runway is about 10,000 feet long, or nearly two miles long; the surrounding land is over 2 miles long). Sold!

So, I left the office early, at 3:45, and grabbed myself a sandwich to eat for dinner once I'd arrived. I caught the 4:03 bus, and we were off. Then we hit Georgetown, and about 20 minutes of unexpected traffic. One of the other riders complained about the slow pace, and how she was going to spend her entire day just getting home. When I finally arrived at my stop, it was 4:48, making it almost exactly a 45 minute ride.

The walk around the south end of the field and up to Kenmore's building took 20 minutes, with a slight delay while I called to get the weather briefing, staying away from the very loud traffic on Airport Way S. I reflected, as I was walking along the 9" wide path through the grass on the side of the road, how oddly happy I was -- it was delightful to be doing something so different from my normal routine, even if it was kind of weird.

Kenmore was pleasant to deal with, and I fired up the engine around 5:20. Boeing ground sent me to the long runway (Boeing Field has two runways: the 10,000 foot runway, and a 3700 foot runway; the 3700 foot runway is 3000 feet longer than I need to take off), which I found fairly delightful. The Champ is an impressive aircraft in some ways. One of them is its take-off performance: 300-400 feet on the ground under conditions like this. The weirdness of having 8000 feet in front of me (leaving from part-way down the runway, at the A10 intersection) was wonderful. I could take off and land several times in that distance.

Flying past downtown Seattle

Norbert the Champ revved up, and we were quickly off the ground, passing through 100 feet as the control tower went past on the left -- it takes off quickly, but it doesn't climb very fast, with all its drag and its small 90 HP engine. We continued straight out, flying over all the Imperial Walker-looking loading cranes on the waterfront, and past the jeweled splendor of downtown's many skyscrapers. I flew over my house in Ballard just for fun, then angled my path northeastward toward Harvey Field.

As I crossed I-5, I looked down benevolently on the poor suckers in their cars, grinding slowly northward. Normally, that's where I'd be, and the difference again delighted me. It's amazing how often the weather screws up my plans to fly to the EAA meeting.

Crossing over I-5's packed traffic

The rest of the trip was uneventful, and I dropped down to land at Harvey Field, shutting off the plane around 6:15. I quickly tucked it away in the hangar, and was to the meeting by about 6:30. Later than I'd wanted to be, but the bus trip had taken longer than I thought it would.

If you're keeping score at home, that's two and a half hours from downtown Seattle to Snohomish -- and I still had another 50ish minute drive home after the meeting.

The Final Score

On the way in to work, on a normal day:

On the way in to work, yesterday:

On the way home from work, on a normal day:

On the way home from work, yesterday:

Total for the day: 121 miles in 5.8 hours: about 20 MPH average, and $0.61 per mile.

Of course, what's not calculated there is how much fun I had doing it. Aside from the patent silliness of what I was doing, I was having a good time the entire time. Even grinding through I-5 traffic in the morning in a taxi driven by a guy who spent more time looking at his phone than at the road was fun, if only in how different it was from my normal daily routine.

In short, it was a good, lightweight adventure. A thrilling change from the normal day-to-day. I'm not likely to do exactly that thing again unless I can figure out a better airport-to-downtown link, but I'm very glad I finally accomplished it after dreaming about it for so long.

Posted at 00:00 permanent link category: /aviation

Sun, 10 Jun 2018

Building a Biplane: The Waiting Game

When I started building the ribs last year, I ordered a bunch of materials: Spruce capstrip (1/4" x 1/4" by 4' long pieces), plywood in 1/16" (!), 1/8" and 1/4" thicknesses, and so on. The Charger plans include some estimates of of the material required to build the ribs: 600 lineal feet of 1/4" capstrip, 24 square feet of 1/16" plywood, 16 square feet of 1/8", 8 square feet of 1/4". I took these numbers as my basis, and ordered about 120% of each of them, since I figured I'd make some mistakes, and it never hurts to have extra.

As I mentioned about ordering wing spars, the shipping on some of this stuff can take a long time. Well, more fulfillment than shipping. Shipping itself is pretty quick, but it can take a long time for the businesses involved to get all the bits and pieces sorted out for an order. Particularly with orders like these, where it has to go by freight instead of normal package shipping, you can't just split it up and ship some of the stuff separately. A freight shipment is a $150-200 proposition for the things I'm ordering.

So the rib materials arrived after a not-too-bad wait last year, and I got to building. I quickly discovered that some of the capstrip I'd received had gouges in the side, and I was assured that this is simply par for the course. However, I lost about 10% of my order to these gouges. Without being finicky about the math, that meant that I only had 10% extra for mistakes and, as it happened, extra ribs "just in case."

This brings me to a month and a half ago, when I ran out of materials with three and a half ribs left to make. I guess I didn't use the 1/16" plywood as efficiently as the designer or something, as I was out of that around the same time I was out of usable capstrip. Since I can't get either material locally, I was stuck.

So, I loaded up my shopping cart at a national aviation supplier to build the rest of the ribs. Then I thought, "You know, I will just need to launch into building wings once the ribs are done, let's see what else I'm missing." More items into the shopping cart until I had about $750 worth of stuff. It took me a week to be sure I had everything I could reasonably predict into the cart, and I finally hit submit. I got a call a few days later: UPS has updated their shipping prices, and it's now cheapest (at $190) to ship this particular order by truck freight. That was weird, but I double-checked, and indeed, the shipping charges for normal UPS package delivery was nearly $400. Fine, ship by truck.

Unfortunately (fortunately?) I had ordered an item that was backordered -- 11 sheets of 0.8mm Baltic Birch plywood for the leading edges -- and it took most of a month before the order was finally assembled for shipment. As it happens, that was June 1st.

Something else happened on June 1st, of course: Mr. Art-of-the-Deal announced 25% tariffs on imported steel. Well, what is my plane going to be made of? About $2300 (pre-tariff) worth of steel tubing, most of it not produced domestically, whether I wanted domestic or not. Faced with a likely $500+ surcharge to stroke his frail ego if I waited, I decided now was the time to pull the trigger on the steel order, too.

Fortunately, I've had the materials list assembled and ready to order for a few months now, hastened by the first rumblings of a steel tariff. I quickly put together the order, and called to get it added to the existing order if it hadn't shipped yet: might as well make the truck shipment charge really work for me, since UPS definitely won't be taking 20 foot lengths of steel tubing in the brown trucks. I was in luck, and the shipment was scheduled to go out on June 1st, but they were able to put a hold on it before it was actually loaded onto the truck.

Downside: more waiting. Upside: reduced overall shipping cost, and I'll have much or all of the hard-to-ship material in hand for the next 5+ years of the project. There will still be many orders to place as I come on new phases and realize just how much stuff I still need.

Unfortunately, all this means that I've had a half-completed rib sitting in the jig for a month and a half, and not much else to do. I've occupied myself in the meantime with some steel work, trying out a technique to machine bushings for the wing compression struts which was successful, but is likely to be time-consuming if I pursue it.

Bushings. I'll be using the right-hand design.

I had thought up until just now that I could only make prototypes for this bushing out of the material I have on hand: mild steel rod. Then I gave it some serious thought (and this is why I need to write more often), and realized that no, the bushing is under practically no stress in any direction, and can be made from mild steel or aluminum, or whatever works. For some reason I was thinking it had to be made from 4130 chromoly steel, which is very strong, but also expensive and likely to be harder to machine. It's nice to occasionally make little positive discoveries like this.

I still have to wait for the 4130 tubing to arrive so I can weld everything together. But at least I have a project I can work on now, while I'm waiting for things to arrive.

Posted at 11:09 permanent link category: /charger

Wed, 21 Mar 2018

The (Other) Long Way Round

If you like real-life adventure stories and are like me, you've probably heard of The Long Way Round, in which Ewan MacGregor and Charlie Boorman ride motorcycles from London to New York by going east instead of west.

But have you heard of the other Long Way Round? It's the story of a Pan Am Clipper crew in 1941 who found themselves caught up in world events in a way they never saw coming.

Read it here: The Long Way Round: Part 1

Posted at 09:41 permanent link category: /aviation

Sun, 18 Mar 2018

Building a Biplane: The Landing Gear Problem

Marquart Charger forward view

The Marquart Charger is generally very well designed, but one of the problem areas over the years has been the landing gear. Thinking about this problem is years ahead of where I am in the build, but it's been bugging me for a while, and I wanted to get some ideas for a fix before I start building any fuselage pieces.

The Charger landing gear is a cantilever design that uses a box-frame leg, which pivots at the lower outside corner of the fuselage frame, and operates a sort of rubber shock absorber/spring under the passenger's feet. It's very clean-looking, since it only has one "tube" going down (most small biplanes have several tubes, forming a kind of 3D triangle).

Because of this single tube design, the pivot point for that tube has to be very strong. In practice, it hasn't ended up being quite strong enough. On top of this, the rubber shock absorber starts out a little bit too stiff, and only gets stiffer with age. The result of these problems combine to show up as cracked fuselages near the landing gear attachments.

Finding a Solution

The problem really breaks down into two issues:

  1. The rubber shock absorber is too stiff, and doesn't provide an effective energy buffer for the gear
  2. The fore-and-aft attachment points for the gear are pretty close together, meaning that braking and rolling-resistance forces are very high

Fortunately, there is a reasonably simple solution for problem #1, which is to replace the rubber spring with a different material. Univair sells the SK-35 Belleville spring kit for the Ercoupe, which is a drop-in replacement for the rubber donuts (also from an Ercoupe according to the Charger plans), and which by all accounts provides a much smoother ride.

The solution to the second problem, though, is one which required (and still requires) a bit more thought.

Marquart Charger gear attachment diagram
The Marquart Charger gear attachment pivot

To this end, I solicited help on the FATPNW Facebook group, and got a couple offers. I just finished up meeting with one gent, B. (to be named later if he is amenable), who discussed the gear situation with me.

A surprising amount of our time was spent getting the existing structure adequately described for him. It's far too easy for me to forget that I've been thinking hard about this subject for a long time, and how clearly I have it visualized. For the purposes of this discussion, I will refer to the part numbers where they exist, from the diagram above.

The chief problem we ended up on was that the -479 part is a little bit too narrow where it meets the fuselage. In the left-hand section of the diagram, you can see the -479 piece edge-on, and you're looking from the side of the plane in toward the inside of the fuselage. In the right-hand section, you see it looking forward. This setup is about the same for both the forward and aft gear attachment points.

Looking at the red arrow on the diagram you can see how the faded red line is a straight line from the surface of the vertical tube to the beginning of the curve around the bottom of the -479 piece. The plans show that divot inward, and B. said that this is likely to be an area of high stress. Flattening out that curve, and making it more tangential to the vertical tube's surface will help to remove that stress concentration. Doing a similar change on the right-hand side of -479, do smooth the transition between -479 and fuselage was also recommended, although it's not drawn in.

The other change he suggested was to increase the length of the strap (the red faded shape on the left side of the drawing), to increase the welded area that attaches the gear pivot to the fuselage.

Charger gear leg diagram
The Charger gear leg

We discussed and discarded a number of other ideas:

These ideas were either pointless (changing part thicknesses), or too complicated (moving the gear attach points).

Generally, the idea he had was to increase the amount of material bearing the stress of the landing gear pivot. As he said several times, it's pretty intuitive. Adding a little bit more steel, and a little bit more weld area, can pay big dividends. It was a gratifying conversation in a way, since that was the idea I'd had as well, but I didn't know if it would negatively impact the stresses in the fuselage in some non-intuitive way.

I particularly like that his proposed solutions amount to a couple ounces of additional weight at most. They're not big changes, but should make a difference in the longevity of the landing gear (assuming I understood the problems correctly; a possibly big "if").

Posted at 14:32 permanent link category: /charger

Tue, 27 Feb 2018

Building a Biplane: The Saga of the Spars

Imagine for a moment that you're embarking on a decade-long project. You know the rough order in which you're going to take your steps, but not how much time each step will take, beyond very rough "Maybe two years?" type estimates.

That was me last June. I made my first wing rib, and started on the long and repetitive task of making a big stack of ribs. I knew from others' experience that the wing spars would take a long time to actually ship. Most people seemed to place an order, and see the shipment about 6 months later. So, I figured, I would order my spars early, and maybe they'd arrive about when I'd be finishing ribs, in the December-ish time-frame.

December has come and gone, and I'm still slowly grinding out ribs, so that timing was inaccurate. Un/fortunately the timing of finishing ribs was the least of my worries.

I placed the spar order with Wicks Aircraft Supply in June. The price was a bit steep, at almost $800 for eight 11- and 12-foot spars. Still, I'd understood that Wicks was the best place to buy aircraft grade Spruce, and I didn't get into building an airplane thinking I'd do it for free.

They didn't provide a shipping or order completion estimate when I ordered, but I knew it would take months, so I put it out of my mind, and worked on ribs.

I got a phone call around September or October with an update on my order: they were still trying to locate sufficient wood of a high enough quality. They knew I was waiting, and asked me to be patient. I said I was, and thanks for the update. I figured we were more or less on track.

Then I got another call on December 1st: we're unable to find enough wood to fill your order. In fact... we're getting out of the Spruce business. Sorry. Good luck.

Wicks explained that they'd had multiple large shipments of Spruce come in, and they simply couldn't find enough high-quality wood to fill the orders they were getting. They were taking a bath on wood orders, so they decided to cut their losses. They implied heavily that the supply of Spruce was simply inadequate to the demand, and that I was probably out of luck getting spars anywhere.

I was, to put it mildly, discouraged.

The next thing I did, though, was go check out the Aircraft Spruce wood selection (I found it ironic too, that Wicks was supposed to be a higher quality supplier of aircraft Spruce than Aircraft Spruce the business was). They listed everything I wanted as "in stock," which seemed like a potentially good sign. Previous experience with them had shown that they were generally on the ball, and if they listed something as in stock, that's because it was.

I also checked a few other options. I called up Steen Aero Lab to see how much they'd want to for a set of laminated spars. A week later, I got the answer: $2300 or so. That seemed like a choice of last resort to me. I contacted an aluminum extrusion company to see if they'd be willing to make a custom extrusion, and how much it would cost, but never heard back.

It seemed like Aircraft Spruce was the best choice, so I called them up and asked them what their expected leadtime was on a set of spars. They went into consultation with their wood department and mailed back a few days later: two to three weeks. Awesome, thought I, and placed the order with them on December 6th.

I'm sure you can imagine my surprise when, 3 weeks later, I had not heard from them. Around the 30th, I called and asked for an update. They eventually got back to me: my shipment would most definitely go out on Janury 30th. Ok, sure. I would have been perfectly happy if they'd told me it would take 3-6 months to ship the order, but they said 2-3 weeks, so now I was unhappy. This is pretty basic business logic: don't make up numbers you can't meet.

It was with a sense of resignation that I watched the 30th come and go without contact from ACS. A week or two into February, I put in a "customer contact" form asking for more information and expressing my displeasure at being misled on multiple occasions. Don't lie to me, I explained, just tell me you don't know, if you don't know.

Several days later, I got a terse response saying that my order would be shipping the next day. Of course, that would put the shipment arriving at my house in the middle of a week I'd be away in Hawaii for my parents' 50th wedding anniversary, so I had the weird role reversal of calling ACS and asking them to delay my order by a week. With visions of one of the spar horror stories in my head, there was no way I was going to allow delivery without me being there to personally inspect the package before signing: one of the Biplane Forum members had his spars delivered in similar circumstances, and discovered that a forklift operator had put the forks clean through the shipping container, destroying the spars inside. He turned the shipment back and had to wait another 6 months for replacements. I don't expect that to happen to me, but for a shipment of this price and fragility, I want to minimize all the risks I can.

And that puts me at now. The spars are supposed to arrive today, in the afternoon. Look for an update below on the actual condition they arrive in. Hopefully they'll be in perfect condition and give me a kick in the pants to get on with my slow-paced rib building so I can move on to building some wings already.

And the expected update:

The spars did, in fact, arrive with damage to the box. The UPS delivery driver and I cut away the outer box and determined that the abrasion damage was only to the outer layers, and didn't go past the second layer of three of sturdy cardboard around the wood. Without realizing I had an choice other than "Send them back" and "Accept the shipment without reservation," I signed on the form, since it looked like the damage was light, and the wood had been spared.

I turns out (news to me), you do in fact have another option. If you suspect that a shipment has been damaged, but it's not so bad you want to send it back, you can note your concerns on the form, something like "Possible hidden damage." Then you sign with that on the form, and UPS is still on the hook even though you've accepted the package. Future damage claims will be substantially easier. Of course, I learned this after I signed for the damaged package.

In any case, a day later, I was able to take the package apart and inspect the contents. The damage did not indeed go further than the cardboard, and the wood appeared to be intact and without problems. I am now the slightly nervous owner of eight lengths of nearly perfect vertical grain Sitka Spruce, which will be carefully stored against the day that I actually finish making ribs, and can move on to the next phase of building a wing.

Posted at 09:15 permanent link category: /charger

Thu, 15 Feb 2018

The Manliest Man Competition

A 30 Second Script

Casting note: no race has been specified for any actor except MAN #3, with the intention that any suitable actor can play a given part regardless of their skin tone. In order to reach the intended audience, we should unfortunately stick with men on stage, and mostly women in the audience. MAN #3 should be white to maximize the impact of the message.

Editing should be very tight. Total length of this piece should be around 30 seconds.

SCENE: Exterior, day. A beautiful sunny day in a rural county fair setting. 4H stalls, Elephant Ear stands, portable merry-go-round, calliope music in the background, etc. Mixed crowd doing the county fair thing, walking with cotton candy and oversized teddy bears from the ring toss, etc. Colors bright and saturated, almost super-reality.

PAN TO wide shot of the main stage.

DOLLY PAST a sign with the stage schedule. "Manliest Man Competition" should be a prominent entry on the list. A sizeable crowd of mostly women has gathered to watch. Eager anticipation is evident.

Slowly ZOOM IN to a stage-wide shot of:

EMCEE: ...don't forget, the Bovine Beauty Contest is happening at the Hewitt pavilion in twenty minutes, by the sign of the smiling cow. And now, what you've all been waiting for, the Manliest Man Competition!

A group of MEN run on to the stage. All are gorgeous body-builder types (IRL the actors will all be gay, of course) with appropriate props in hand.

EMCEE: Without further ado, contestant number one, show us what you've got!

CUT TO close up of MAN #1, who is holding a football. He picks an AUDIENCE MEMBER at the edge of the crowd, and urges them to go way back.

CUT TO close up of AUDIENCE MEMBER running into the distance: they know what MAN #1 is capable of.

CUT TO close up of MAN #1, who winds up and throws the football.

SFX of a jet engine spooling up as he winds up, and an explosive take-off noise as he throws.

VFX the football disappears into the distance.

CUT TO a wide shot from the back of the crowd, overlooking crowd and stage. The crowd erupts in applause. MAN #1 smiles winningly and bows.

CUT TO a close-up of the EMCEE.

EMCEE: Wow! Contestant number two, beat that!

CUT TO a close-up of MAN #2 who is, if anything, even more dashing and handsome than MAN #1.

MAN #2 beckons to one of the ladies in the AUDIENCE, who is attractive, but not petite. Our AUDIENCE MEMBER could be another man, but this might distract from the message for the intended audience of this piece.

CUT TO a close-up of the AUDIENCE MEMBER doing a silent, flattered "Who, me?" routine.

CUT TO a wider shot showing our AUDIENCE MEMBER being easily lifted on stage by MAN #2.

CUT BACK TO a close-up of MAN #2, who rips off his shirt, places the AUDIENCE MEMBER on his back, and proceeds to do one-handed push-ups with effortless grace.

SFX: A subtle thudding noise at the bottom of each push-up, as if MAN #2 is making the ground shake.

AUDIENCE: Ooooooooh.

The AUDIENCE applauds gently, awed by the feat.

CUT TO a stage-wide shot as MAN #2 gracefully hands the AUDIENCE MEMBER back down into the crowd to applause that ratchets up to being thunderous.

EMCEE: Contestant number three!

CUT TO close-up of MAN #3 who is somehow even more ripped and beautiful. He smiles winningly at the crowd, and pulls a tacti-cool AR-15 rifle from out of nowhere, Bugs Bunny style. It is equipped with numerous accessories like a bayonet, scope, laser, foregrip, etc.

CUT TO wide shot encompassing audience and stage, again from the back of the crowd. There is a beat of silence as everyone takes this in.

AUDIENCE laughs uproariously and humiliatingly. Pointing and jeering. Booing. MAN #3 visibly deflates, and slinks off stage. MAN #1 and MAN #2 look after MAN #3 with pity and mild scorn, shaking their heads at his misguided attempt.

ZOOM IN on an AUDIENCE MEMBER, who is lauging and wiping their eyes. They turn organically to the camera, and interspersed among the laughter:

AUDIENCE MEMBER: He thought a gun would make him manly? What a dupe! [more laughter]

FADE TO black.

SFX: Audience laughter continues into the black, taking on an echoing quality.

Do not add any titles or VO at the end. The viewer should be left with ringing laughter in their ears and nothing else.

Posted at 14:49 permanent link category: /misc

Categories: all aviation Building a Biplane bicycle gadgets misc motorcycle theater