It depends on the ejection seat.

Modern zero-zero ejection seats are designed to be usable at zero speed, zero altitude.

Older ejection seats had different minimums which varied from model to model.

On a side note, the early F-104 ejection seats required quite a bit of altitude to deploy properly, since the pilot exited through the bottom of the aircraft.

This was done because there was some concern that the pilot would hit the F-104's T-tail with a standard ejection seat.

EDIT

It appears that it may actually be possible to eject from an inverted aircraft.

According to Wikipedia (bold added for emphasis): The minimal ejection altitude for ACES II seat in inverted flight is about 140 feet (43 m) above ground level at 150 KIAS.

While the Russian counterpart - K-36DM has the minimal ejection altitude from inverted flight of 100 feet (30 m) AGL.

When an aircraft is equipped with the Zvezda K-36DM ejection seat and the pilot is wearing the КО-15 protective gear, he is able to eject at airspeeds from 0 to 1,400 kilometres per hour (870 mph) and altitudes of 0 to 25 km (16 mi or about 82,000 ft).

The K-36DM ejection seat features drag chutes and a small shield that rises between the pilot's legs to deflect air around the pilot.

Pilots have successfully ejected at negative altitudes in a handful of instances, after being forced to ditch in water.

Documented evidence exists that pilots of the US and Indian Navies have performed this feat.

Also: I once read, but cannot now locate, the citation awarded a pilot of the USAF for the world record lowest altitude successful (i.e. the pilot survived) emergency ejection from a stricken aircraft over land: sixteen feet below ground level.

Apparently the young pilot was practicing with his T-33 single-engine trainer when the engine flamed out and could not be restarted.

The pilot observed the flat desert below, crossed by several paved roads and highways.

One road seemed to be completely clear of traffic, so he opted for a gear-down dead-stick landing on it, hoping to minimize damage to the aircraft.

He discovered only after touchdown that the paved strip was not a road at all but a flash flood drainage ditch, wide enough for the fuselage but not the wings.

The aircraft was seriously damaged and set on fire.

The damage prevented the canopy from opening, so the pilot used the ejection seat to escape burning to death.

He survived with minor burns, some compression damage to his spine, and two broken ankles.

The Martin Baker MkGRU7 and EA7 on both the A6 Intruder and on the EA6B Prowler aircraft

have "zero-zero" capability, which means that the seats could be fired at zero AGL and zero airspeed.

Quite a few years back, about 28 to be exact

I worked on Mirage III service for the RAAF and one of my jobs

was to fit the ejection seats after major airframe servicing.

Originally they were fitted with Martin Baker OM6 and these seats were zero-90 classification.

They were powered by cartridges, basically a big multi stage canon that shot you out of the plane.

This means they were able to be used at zero altitude and 90 knots forward speed, the speed was purely to have enough air flow to open the chute fully but mostly to help with the removal of the canopy by blowing it backwards.

The canopy jettison would unlock the canopy and lift the front into the airstream, the forward motion would do the rest.

Later we made a modification to the seats to make them into zero/zero capability and this included fitting a rocket pack under the seat that would launch the seat to a safe height enough for the parachute to open normally.

In both cases the seats were capable of going through the canopy but normally the canopy would eject first except in the zero zero situation where the seat would go through the canopy.

It all depends upon the seat type, altitude, speed, attitude and orientation of the aircraft during the ejection process.

Ejection seats just provide a velocity vector in order to give the pilot enough time to clear the crippled aircraft and deploy the recovery parachute, as this USAF training film shows.

This results in an envelope of airspeed, altitude, and attitude in which the seat can be activated allowing for a safe recovery.

For a so called 'Zero-Zero' ejection seat, it allows for a safe ejection from an aircraft on the ground in level flight attitude.

It does NOT guarantee safe ejection from an aircraft in unusual or inverted attitudes at low altitudes or airspeeds.

In the Boeing ACES II ejection seat a basic guide to seat characteristics is given here.

I can't comment on the capabilities of the Russian seats.

However the Russians do have a tendancy to be excessivly boastful and colorful with a gullible western press, such as the 1989 crash of a MiG-29 at the Paris Airshow, where the press ran with a story about the K36 seats being able to safely eject at low altitudes and extreme attitudes.

The reality was the seat in this incident was activated outside of its safety envelope; the pilot was just lucky he wasn't killed.

Question: Is there generally a minimum altitude for ejecting in order for the sequence to function reliably (all the way to opening the chute, and slowing down to a survivable descent rate)? I've seen ejector seats test being done on the ground, don't know if there were actually test pilots in those seats though.   I assume all bets are off if you're not wings level (obviously a low-level inverted ejection has a 0% chance of success).

Is there a minimum altitude for ejection seats?

It depends on the ejection seat. Older seats have different minimums. Modern  zero-zero ejection seats  are designed to be usable at zero speed, zero altitude.  Pilots have successfully ejected at negative altitudes  in a handful of instances, after being forced to ditch in water.

It depends on the seat type, modern seats can be deployed even at 0 altitude and 0 speed

Users tend to agree that it depends on the seat type.


A great site to download airport diagrams and other charts is charts.aero .

As of April 2015, however, the site seems gone.

Airport diagrams show all the taxiways and ramps, which is what you are looking for.

Keep in mind that this is an unofficial website.

The charts should not be used for actual navigation.

In the US, you can find this on the FAA's website here .

You can search for a US Airport, and it will pull up a Airport diagram with Taxiways, Runup areas, and Runways on it.

I couldn't find an official guide for European airports, but this site has a detailed guide for CDG , among others, with a taxiway map being one component.

They also have a similar guide for AMS .

They do not have one for PRG.

Keep in mind these are unofficial charts.

As Lnafziger noted, this site also has airport charts, including approaches.

The downside is you must register (free) first to access them.

You can read more in this answer .

If you look up the ICAO code, e.g. here http://en.wikipedia.org/wiki/International_Civil_Aviation_Organization_airport_code

then Google for the code

+ charts, e.g "EGLL charts"

, you will usually find what you're looking for. https://www.google.co.uk/search?q=egll+charts

Airport ground charts are always part of the AIP (Airport Information Publication).

They are usually publicly available in electronic format, but not always easy to find.

Wikipedia's entry for AIP has a For european airports, you can get them from Eurocontrol (requires registration).

However, you can also usually get these directly from the country's CAA or AIS.

Here's the ones you asked for (be aware these links may only work for a short period of time): Paris CDG .

Amsterdam Schiphol .

Prague .

Just stumbled across this directory, hosted by VATSIM.

Doesn't appear to be entirely up to date but does provide a link for charts for Prague, among many others.

(Includes links to content that may be behind a paywall though). http://www.vatsim.net/charts/

Question: Whenever I sit in an aircraft and we taxi around the airport, I wonder how exactly is the airport organized, for example, the arrangement of the taxiways and runways.  Is it possible to locate airport diagrams? I'm mostly interested in Paris CDG, Prague PRG and Amsterdam AMS.

Are the airport "taxi" plans available online?

A great site to download airport diagrams and other charts is  charts.aero. You can also find airport diagrams that show all the taxiways and ramps.

You can find such information on charts.aero, on the FAA website or on the individual airports websites.

There are a number of places where this information can be found.


It would actually miss the point of wind tunnel testing.

A free flying model could only be subject to air stream in speed and direction so that the forces are balanced.

A fixed model on the other hand can be subject to air stream of any direction and speed and the forces measured.

It is important to measure the forces under those conditions too.

Could you?

Yes, probably, but it would be very difficult due to the very limited space.

You would have to have a huge airflow in excess of 50 knots for a small aircraft, and you could not simulate any motion fully, such as takeoffs rolls.

You could also not test stalls and other manoeuvres.

I think the main reason against this is that this is simple areas of flight dynamics that can just as well be done with computational fluid dynamics on a computer for a fraction of the effort and cost.

I don't think it would be safer either.

It's a very confined space, and you couldn't cut the airflow very quickly, so it's probably more dangerous than flying outside with unlimited space and a stable airflow.

You certainly could fly a completely assembled aircraft in a sufficiently-large wind tunnel -- at least in theory (theory is an awesome place - everything always works there.

When I retire I'm moving to theory).

In reality there are lots of drawbacks which have already been pointed out, but there's one that hasn't been yet: Wind tunnel testing is traditionally done with scale models, and even then it's not "cheap"

: It takes a lot of power to move wind through a tunnel at high speed, and scaling this up to a full size airframe - even small-airplane size like your typical Cessna or Piper trainer - is cost-prohibitive since you would have to build the entire plane and then pay to blow high-velocity air over it.

( There are wind tunnels at this scale though - at least one.

NASA spent a lot of money on it, and then Boeing and Airbus came out with their new super-jumbo planes which don't fit!)

It's also worth pointing out that the kind of fluid dynamics modeling that used to be done with wind tunnels and smoke trails is now often done with Computational Fluid Dynamics (CFD) software .

Cheaper, Safer (no risk of parts blowing off and bouncing down the tunnel), and more accurate in many regards -- but nowhere near as much fun to watch :)

There have been tests of real aircraft in wind tunnels, with a pilot sitting in the cockpit.

But in all cases the plane had been tied in place with strings.

Trimming the lift and especially the thrust in all phases of the test is really impossible.

The Messerschmitt 109 was tested in the French Chalais-Meudon tunnel in 1940, the Bell P-39 was tested at Langley, where the top speed could be improved from

340 to 392 MPH, the P-51 was tested at Langley in 1943 like most small military planes of that period, and lately a stealth demonstrator made by MBB was tested in 1984, in most cases with the pilot in place.

These are the ones I know; there were certainly more.

Yes you can.

Yes it has been done.

And yes people are still doing it.

The caveat being that most (all?) of the tests are done with scale models rather than full size planes.

Free flight wind tunnel tests are done for different reasons from static mounted tests.

Where static mounted tests are done to collect measurements of forces acting on the aircraft/part, free flight tests are done to understand

/confirm the stability of the aircraft.

Flying a model plane in such confined spaces is very difficult and typically the plane will tend to wander around in the wind tunnel.

As such, the data that you can get from a free flight test is very limited.

Due to the difficulties of doing the test and the limited amount of data you can get from it

most new plane designs don't go through such a test.

Instead, what typically happens is that the design goes straight to a radio controlled scale model that is flown outdoors to study its stability.

However, when trying out new ideas that has not been developed it is still worth doing the stability tests in a controlled environment - in a large wind tunnel.

Here are some old videos of free flight wind tunnel tests (these come from a time period where the behavior of delta wings were not yet fully understood): https://www.youtube.com/watch?v=OGmigdhxMRw https://www.youtube.com/watch?v=aDIQc3-umf4

Here's a more recent video of a free flight wind tunnel test of the Blended Wing Body: https://www.youtube.com/watch?v=B7zMkptajMQ

No, you cannot fly a plane like that.

Problem is: propulsion is missing.

Once you expose a plane model to an airstream, the airfoils (wings) start producing lift but also drag.

In real world, an airplane requires propulsion to overcome the drag (induced drag,parasite drag,..)

in order to move forward.

The wind tunnel airplane model would just lift-off and fall behind, there would be no chance to establish a stabilized flight attitude where propulsion equals drag and lift equals weight.

Such a stabilization is required to seriously start measuring.

That's why the models are strapped down to a pylon or whatever.

Measuring results can therefore also be reproduced (certain fixed AoA's at certain airstream speeds etc.)

Question: There are  very large wind tunnels  out there. Wouldn't it be very efficient to test new airplanes flying them "on the spot" inside of these tunnels? That is, in free flight - not mounted to a pylon? One could presumably omit the test pilot and remote control them, get excellent visual feedback and have a completely controlled environment. Has this been done? If not, why?

Can you fly a plane in a wind tunnel?

You certainly could  fly a completely assembled aircraft in a sufficiently-large wind tunnel. There have been tests of real aircraft in wind tunnels, with a pilot sitting in the cockpit. The caveat being that most of the tests are done with scale models rather than full size planes.

While in theory you could fly a plane inside a wind tunnel, even with the limited space, and it has been done, you could not really test stalls or other maneuvers, there would be no propulsion and you would need a huge amount of airflow.

People say it is possible and it has been done.

People say it would be difficult or impossible.


There is no difference between civil and military aircraft.

Not the least because the civil and military transport aircraft are actually the same models .

Many military planes have civil variants like Lockheed C-130/ L-100 , other military planes are derived from civil ones, e.g. C-135 is B707.

The difference depends on where the wings and engines are placed.

All the aircraft actually have similar clearance from the ground.

Just on some the lowest point is fuselage, on others

it's the engines hanging down from the wings and on propeller driven ones it is often the propellers.

Cargo planes (like C-130, C-5, An-124 or An-224) are often built with high wings, so the fuselage is lower and therefore easier to load.

This is also concern for regional airliners as they are designed to carry their own stairs.

That's why BAe146 , ATR-42 or Dash-8 are high-wing and other like Bombardier CRJ series have tail-mounted engines so they can also be lower.

On the other hand low or mid-wing designs with wing-mounted engines have better aerodynamic properties, which is why that construction prevails for large airlines.

Easier to Load As stated earlier, this is your primary reason.

You have to be able to load in cargo from the ground.

If you want to get troops and vehicles in fast to somewhere with minimum equipment, you want to be able to roll them of the aircraft, and the lower the aircraft, the easier this is done.

Other considerations:

Shorter gear is stronger

The longer you make the gear, the more it will bend.

Bad news if you're trying to land on rough ground.

More Cargo space

The shorter you make the gear, the less trouble you have finding space for it inside the aircraft, where you want to maximise the amount of space you have for cargo, especially for vehicles and the like.

The anatomy of a cargo aircraft is that they are typically hollow inside, unlike passenger aircraft where they fold up into the center section.

Landing gear is heavy Landing gear is very heavy, since its got to support the weight of the entire aircraft above.

The shorter you make it-

the lighter the aircraft gets.

Better use of ground effect

The low gear may bring the aircraft a little bit closer to the ground, maximising ground effect and lowering your landing speed, again very ideal for rough terrain.

Note: These don't only apply to military aircraft, but to a lot of commericial ones as well, since the benefits are the same.

Look at the Dash-8, ATR 42/72, BAe 146 along with the rear-engined planes, and they all try to do this for these reasons, although ease of cargo loading might not come first on the list.

For the aircraft you use as examples the aircraft height above the ground (landing gear height) is mostly a function of use-case and clearances.

For the Boeing and Airbus airplanes you mention, the gear need be long to accommodate the engines hanging under the wings as well as the minimum bank angle needed to avoid wing strikes.

On the other hand, the C-130 has the engines mounted up on a high wing and the aircraft needs to handle big slow heavy things like tanks being driven into the cargo.

The need of the tanks specifically probably mandates the interior floor be pretty close to the ground, or you might need extremely long ramps to for the tank to ascend (and these would pose their own problems).

C-130 Addendum Purpose-designed for cargo - rather novel at the time back then, perhaps.

Look at WWII films of the C-47 or Berlin Airlift film of

C-54 's.

How the heck do they get anything in there?

Designed around a "standard truck bed height" floor and a "standard railroad box car" dimensions - 10' x 10'.

The short landing gear derives from the basic design goals.

Further, the wheels are in tandem - one behind the other vice side by side.

And the tires are fat.

These aid operating out of unimproved/dirt fields.

The leading tire "plows the way" so to speak for the rear tire.

Fat tires lowers the "per square foot" weight on the tires.

The longer you make the gear, the more it will bend.

Bad news if you're trying to land on rough ground.

Ironically the C-130 landing gear is wimpy when it comes to side loads.

It does not have adequate side-bracing.

Straight ahead, we can pretty much plop that puppy on the ground relatively aggressively.

But, during taxi, stopping while still in a turn is a write-up and requires maintenance inspection prior to flight.

The first possibility that jumps to mind is that one is more comfortable than the other, The C-130 is designed for utility, by masochists.

It is painfully loud, too cold and too hot at the same time, vibrates like the inside of a jack hammer; and if the the prop synchro-phaser ever fails will drive you insane in short order.

The biggest factor in landing gear length is going to be how the engine(s) is/are mounted and ensuring they have clearance.

The C-130 and turbo-prop commuter airliners (Embraer and Bombardier) have the engines in line with the bottom of the wing which is attached to the top of the fuselage.

Large airliners (Airbus and Boeing) have engines slung well under the wings which attach near the bottom of the fuselage.

The turbo props get a lot of clearance from the height of the fuselage while the jets rely on longer gear legs.

Question: Why do military aircraft have a lower landing gear than civilian? I have in mind the difference between a Lockheed C-130 Hercules and a Boeing or Airbus.   The first possibility that jumps to mind is that one is more comfortable than the other, which is more robust. But would an aircraft designer reduce robustness to provide more comfort?

Why are military and civil aircraft landing gear generally so different?

There is no difference between civil and military aircraft. Civil and military transport aircraft are actually the same models. The difference depends on where the wings and engines are placed.

There is practically no difference between the two, however it does depend on where the wings and engines are placed. It is also a fact that shorter landing gear is stronger.

Users say there is practically no difference between the two.

However it does depend on a number of factors.


The only term in the Pilot Controller Glossary is Go Around, so should technically be the only term used, at least when communicating with ATC: GO

AROUND- Instructions for a pilot to abandon his/her approach to landing.

Additional instructions may follow.

Unless otherwise advised by ATC, a VFR aircraft or an aircraft conducting visual approach should overfly the runway while climbing to traffic pattern altitude and enter the traffic pattern via the crosswind leg.

A pilot on an IFR flight plan making an instrument approach should execute the published missed approach procedure or proceed as instructed by ATC; e.g., "Go around" (additional instructions if required).

(See LOW APPROACH.)

(See MISSED APPROACH.)

The ATP PTS also includes a Rejected Landing, which is what our simulator instructors refer to as a Balked Landing, and must be at or below 50 feet AGL.

It has the following note describing it in the PTS: NOTE:

The maneuver may be combined with instrument, circling, or missed approach procedures, but instrument conditions need not be simulated below 100 feet above the runway.

This maneuver should be initiated approximately 50 feet above the runway or landing area and approximately over the runway threshold or as recommended by the FSB Report.

The pilot follows the same procedures for both of them by aborting the landing, cleaning up the airplane, and flying the appropriate procedure afterwards.

Almost everything I read says that a balked landing is the same thing as a go-around.

(Indeed, the wikipedia page for balked landing redirects to the 'go-around' page).

In these cases, a balked landing, also known as a go-around, creates a better opportunity for a near perfect landing [ src ] A balked landing – also known as a go-around, is an aborted landing of an aircraft that is on final approach … for landing [ src ] This thread mentions that they are the same as a go-around, but can include when the wheels briefly touch down.

However, I did find one slightly dissenting opinion here : I don’t know of an official definition of a balked landing that makes it different from a go-around.

The way the balked landing term is generally used is that the actual landing procedure has begun and must be aborted.

A go-around generally begins at a higher altitude and lacks the urgency of the balked landing.

So, in summary, they're pretty much the same thing (or exactly the same thing), but some people differentiate the two by the altitude the procedure begins at.

While there is no distinction between balked landing <-> go arround, "technically" you will find in regulations a difference between balked landing and missed approach .

Missed Approach climb is defined as a go-around from at or above DH (possibly with one engine inoperative).

CS(Part

) 25 assumes required gradient on: Go-around thrust on remaining engines

Landing gear retracted Approach flap set

Balked Landing climb is a go-around from below DH, possibly in the flare

(note that all engines are assumed available).

CS (Part)

25 assumes required gradient on : Go-around thrust all engines Landing gear down Landing flap set

Balked Landing is a very low altitude Go-Around.

Not a term you would use with ATC, they don't care.

It's a term found in certain aircraft flight manuals and requires a slightly different procedure than a normal go-around, similar to a rejected landing.

Usually wheel touchdown is likely and you must verify airspeed increasing past a certain point (safe flap retract speed) and positive rate of climb before de-configuring, otherwise you risk touching down with the gear in transit or slamming down because of loss of lift from flaps/slats.

The missed approach procedure is published with considering the terrain in the area.

It is calculated that an aircraft can safely go around clearing the terrain if it starts go-around at the DH.

If the aircraft descents below DH, and decides to go around things go different.

Because now it starts the procedure approximately 200' below and also 1NM ahead of the published missed approach procedure.

This is a balked landing, and has to be handled with more care.

to carry out the engine out SID after balked landing in low visibility conditions also has to be considered

A balked landing is a go around in the landing configuration: flaps and slats at the required setting, gear down, etc.

A go around can be performed in any aircraft configuration.

Balked Landing – A discontinued landing attempt.

Term is often used in conjunction with aircraft configuration or performance assessment, as in “Balked landing climb gradient”.

Also referred to as “Go-Around”

Balked landingd it is not a simple go around or missed aproach landing, in a balked landing the airplane must be able to maintain a steady gradient of climb of at least (different for each airplane)with: (1) Not more than the power that is available on each engine eight seconds after initiation of movement of the power controls from minimum flight-idle position; (2)

The landing gear extended; (3) The wing flaps in the landing position; and (4)

A climb speed equal to VREF, available: http://www.risingup.com/fars/info/part23-77-FAR.shtml

A baulked landing and a go around are very much TWO different procedures.

A baulked landing only happens on very short final if for instance the captain isn’t happy with what they see.

The procedure is simply to pitch nose up and simultaneously apply full power.

The wheels may touch the runway but that is fine.

This is an escape maneuver to quickly get away from the ground.

Once the aircraft is in a stabilized climb, the go around procedure can be applied.

This is initiated by a term like “Go around, flaps” which helps bring both pilots back into the loop.

A go around procedure always follows a baulked landing, but a go around procedure can of course be flown on its own.

Question: Is there a difference between a balked landing and a go-around?  If there is, what exactly is a balked landing?

What's the difference between a balked landing and a go-around?

The only term in the Pilot Controller Glossary is Go Around.  A balked Landing is a very low altitude Go-Around.  A balked landing only happens on very short final if for instance the captain isn’t happy with what they see.

People are of devided opinion when it comes to this. Some say it is basically the same thing, only depends on where you think the procedure starts, and others say that they are two procedures entirely, a baulked landing being a low altitude go-around.

Users say that it is basically the same thing

Other users suggest it is a different procedure entirely


I think most people would say the answer is no .

Consider the dictionary.com definition as it relates to Aeronautics: 9.

Aeronautics .

a. one of a pair of airfoils attached transversely to the fuselage of an aircraft and providing lift.

b.

both airfoils, taken collectively.

The wings are the big airfoils which are responsible for generating most of the vertical lift.

A colloquial test of this definition would be to grab a CFI and ask him/her to "point out the wings on this airplane to me.

" They won't point out the propeller.

( Not a scientific experiment )

However, both wings and propellers are airfoils (and so are the other wing-like surfaces such as the vertical and horizontal stabilizers).

You might get some disagreement about whether those other surfaces are wings, but I believe the answer is still no.

There is nothing to be gained by calling them wings, and only leads to ambiguity.

We already have a word which describes lifting surfaces in-general, and again, it's airfoil .

Is a propeller a wing?

Maybe.

It depends on how pedantic you feel like being about your definitions.

A propeller is certainly an airfoil (usually several of them - each blade is an airfoil, and you can have one blade , two, three, four, or more attached to a hub).

A wing is also an airfoil.

Aerodynamically a wing and a propeller function the same way:

Air moves over the surface of the airfoil(s), producing "lift".

In the case of the wing the lift is mainly vertical and we call it "lift", while in the case of a propeller it's mainly horizontal and we call the resulting force "thrust" instead.

My two cents, ignoring all the dictionary pedantry?

A propeller is an airfoil, but it is not a wing.

Why?

Simple: If I'm flying along and my propeller magically vanishes I'm now flying a really inefficient glider.

My day is ruined and when I catch the guy with the genie-in-a-lamp who wished my propeller away I'll probably beat them up, but I have a fair chance of putting the aircraft on the ground without killing myself or anyone else.

If I'm flying along and my right wing magically vanishes the genie-posessing miscreant is safe as I'm almost certainly going to die.

All the lift from the remaining wing is going to try to flip the aircraft over, and I'm nowhere near skilled enough to keep control with a missing wing and land safely .

An aviation expert reminded me that a propeller is a wing.

This is not false- a wing generates lift by creating a pressure difference, in the same way a propeller does.

Wing typically refers to the structure lifting the main weight of the aircraft, while a propeller generates thrust, so from definition it's probably incorrect, from a theoretical standpoint

it's the same principle.

While I understand that propellers use similar principles to generate force, it muddied the definition of a rotary wing aircraft vs a fixed wing aircraft.

A fixed wing aircraft will move at speed to generate sufficient lift to get airborne.

A helicopter will be able to lift off vertically by spinning the blades quickly enough, which will have the same effect as moving forward.

If the propeller of a fixed wing aircraft is considered a wing, what is the distinction between the two?

Is it how much surface area

each type of wing works on?

Is it the direction of force?

Propeller thrust is directed forwards.

In level flight it contributes very little to lifting the plane up-

that's left to the wings to do.

Rotary wing aircraft's blades do really work as a propeller: By increasing the angle of attack on one side, you generate more thrust, and the helicopter flies in the direction you want it to, since there's a force vector in that direction.

(source: tiscali.co.uk )

Distinction between the two: Rotorcraft generate the thrust to lift off themselves.

A propeller generates the thrust (and in turn speed) necessary to create lift over fixed surfaces.

Since no one else mentioned this, I thought I would.

Wilbur Wright, of the Wright brothers, said that a propeller was nothing more than a twisted wing.

If you accept his analogy, then the twisted wings that compose a propeller are clearly specialized wings, but they do generate a differential in air pressure above/in front of and below/behind as the surface moves through the air.

That is what a wing does.

When one thinks with respect to plane, things are a lot less "muddy".

Forget about definitions and rote and focus on what the function is.

First, while airborne, the only thing with respect to ground is gravity.

Everything else is dependent on orientation of the aircraft.

This is not muddy, it is actually a crucial step in becoming a better pilot.

So, starting with straight and level flight, it is obvious what is the wing (lift) and what is the propeller (thrust).

Now pitch up, add power and climb.

Yes, the propeller is now helping you climb as well as maintaining airspeed.

Is it now called a wing?

No, it is still out in front of the plane, so, with respect to plane, it is still the propeller!

The key is to draw the thrust vector, then break it down to vertical and horizontal components.

The propeller is helping lift the plane.

Now rotary wing aircraft.

All lift is provided by spinning the rotor, and forward motion too!

So it is both wing and propeller.

Birds have learned this trick as well!

So do not worry about muddy, take what you need and fly.

Question: An aviation expert claimed to me that a propeller is a wing.  While I understand that propellers use similar principles to generate force, it muddied the definition of a rotary wing aircraft vs a fixed wing aircraft.  If the propeller of a fixed wing aircraft is considered a wing, what is the distinction between the two?  Is it how much surface area each type of wing works on?  Is it the direction of force?

Is a propeller a wing?

A propeller and a wing are certainly airfoils.

It depends on the definition, as a wing and a propeller are both certainly airfoils. However most people would say no it is not.


The device you are talking about is called a transponder .

This is a device that listens for a signal (an interrogation) and responds with information about the airplane including an ATC assigned code, altitude information and additional aircraft info for certain equipment.

There are 2 ways ATC watches airplanes: Primary Radar Secondary Surveillance Radar

The transponder is interrogated by the Secondary radar and the response is listened for.

Even with no transponder, the aircraft can still be tracked by primary radar.

This is just a normal radar that is good at seeing airplane sized objects and not so great at seeing weather and can occasionally spot a large flock of birds.

The primary radar is what provides the "blip" on radar and tracks the airplane.

The datablock ATC has on the airplane comes from the secondary, so what ATC will see is a blip with no information.

Turning off the transponder is as simple as setting it to OFF or pulling a circuit breaker and yes, it can be selected OFF in flight, it is just a switch.

The problem with radar is that it only works so far from a radar transmitter and the further away

you are the higher

you must be to be seen by the radar.

Over the ocean away from land, you are going to be on the fringe of radar or out of radar contact completely and thus unable to be tracked directly by ATC (at this point, non-radar procedures such as position reporting and ETAs can be used to track positions).

The flight in question was apparently visible by a military radar before it disappeared from the scopes (it allegedly observed what appeared to be a turn back toward its origin).

With the proper knowledge of the aircraft systems almost anything can be turned off.

That's what we do at the end of almost every flight day.

Most of the communications systems can actually be turned off fairly easily, but the average person would not know how to do it.

In airplanes like the 777, there are multiple ways that they communicate but all of them can be turned off (transponders, ACARS reports, CPDLC, ADS-B, radios, satellite phones, etc.).

Some are automatic and some are manual, and not all aircraft have all of them.

Most of them have a switch or can be controlled through the Flight Management System, but the ones that don't will have a circuit breaker designed to protect the system which may be pulled in order to deactivate the system.

As a B-737 pilot, I can tell you that ALL electrical components are wired into the electrical system to a specific electrical BUS.

It would not be hard to determine which BUS(S) run power to the associated component and therefore knowing which circuit breaker(s) to pull.

The ACARS that transmits our FOQA information can be disconnected on the BBJ I fly.

I assume it can be done in the B-777.

With today's locked cockpit policy it is extremely unlikely that hijackers would be able to turn off the transponder without pilots being able to set it to 7500, the code for unlawful interference, for at least a short while.

Because while the transponder can be turned off, the hijackers would have to get into the cockpit first.

The cockpit door can't be opened from cabin side.

Even if the stronger code is entered that will open the door (for cases when one pilot is incapacitated while the other is in the lavatory) the pilots still have some time to cancel the unlock request.

Therefore the hijackers would have to threaten with something to get the pilots unlock, but that would give the pilots time to provide some indication of the hijack to the ATC.

Another Boeing 777 on 12th July 2014 suffered smoke in the cockpit and cascading loss of electrical systems, navigation displays and Comms in the cockpit.

That was Continental Flight 201 which made an emergency landing on Midway island.

There are disputed claims that flight 201's transponder also failed during the emergency.

In the case of MH370 it is acknowledged that the ACARS suffered a power interruption prior to log-on requests.

It seems possible that the transponder was affected by whatever power interruption the ACARS suffered therefore it is not an automatic assumption that the transponder and ACARS were turned off deliberately.

The plane's position is reported by ACARS and by the transponder.

MH370 lost ... ... its Mode S transponder (shortly before 17:20:33 UTC) ... ACARS (somewhere between 17:07:49 - 17:37:29 UTC) ... and the SDU (somewhere between 17:07:49 - 17:37:29 UTC).

The SDU was repowered, however, at 18:25:27 UTC, when it logged onto theInmarsat satellite network again.

The first 2 items can be easily disabled in the cockpit.

The SDU can be disabled by either turning off the AES circuit breaker in the E&E bay or depowering the left main AC bus in the cockpit (which results in the collateral loss of various systems).

India has made it mandatory for aircraft flown by Indian operators to install a device reporting the aircraft's location every 15 minutes, thereby preventing the aircraft from disappearing:

India makes its aircraft disappearance proof post MH370 incident «

India has taken several steps to remove any possibility of the aircraft operated by its airlines disappearing without a trace in the aftermath of the shocking incident in March 2014 involving Malysia Airlines’ MH370.

It has made it mandatory for aircraft flown by Indian operators having a seating capacity of 19 passengers or takeoff weight of 45 tonnes or more to install a devise that will send location of the aircraft at 15 minute intervals.

The government had ordered airline companies to compulsorily install an automated aircraft tracking system (ATS) in all aircraft falling in the above categories.

The system will pass location information to ground stations even if the aircraft is flying over the oceans during long international flights throughout the duration of the flight.

» ( source )

Question: I was speaking to someone about the  MH370 incident , and they suggested that a hijacker could turn off the device that sends the plane's current position, resulting in the appearance of a catastrophic midair failure.  I assume that such functionality could not be turned off, but I could be wrong. Is there any way that this could be done? Could an aircraft's internal tracking systems be "turned off" midair, and also not be located by external tracking like radar?

Is it possible for a modern commercial airliner to stop being tracked without substantial mechanical failure?

The device you are talking about is called a  transponder. The plane's position is reported by ACARS and by the transponder.  With the proper knowledge of the aircraft systems almost anything can be turned off.

The transponder reports the position of the aircraft, this can be disabled from the cockpit. However the plane can still be tracked by normal radar.

Users provide information on the operation of transponders in aircraft


The angle of attack is the angle between the wing (wing chord to be precise) and the direction of travel (undisturbed airflow).

The angle of pitch is the angle between the main body axis and the horizon.

The difference can theoretically be any angle, but during normal flight it will be limited to about 15 degrees.

The reason that the angle of attack sensor was inoperative was due to low airspeed.

Below 60 knot IAS the indication is unreliable and therefore the indicator is inhibited.

This also inhibits the stall warning.

This lead to the confusing situation that lowering the nose to correct the stall increased the airspeed beyond 60 knots, thereby reactivating the stall warning.

It can be.

Remember that the angle of attack is the angle between the chord line of the airfoil and the relative wind.

Imagine if the plane is level with the horizon with zero airpseed.

It will fall straight down, putting the angle of attack close to 90 degrees with the pitch close to zero.

That said, during normal flight it's not likely that pitch and angle of attack will be excessively different.

But honestly the two aren't closely related: You can exceed the critical angle of attack and stall at any pitch, bank, or yaw angle.

Just want to add the image.

Angle of attack is relative to the direction of relative wind (which is equivalently relative to the direction the plane is going, if in still air and the angle of incidence = 0, i.e. the wing is mounted parallel to the longitudinal axis of the plane), while pitch is relative to the horizontal axis.

Angle of attack depends on the pitch, current velocity of the aircraft and the wind.

They can be different.

Angle of attack is important to the aerodynamics (amount of lift, drag, etc.), while pitch tells you the aircraft's orientation relative to the ground.

Image source Assumptions for the image: still air and angle of incidence is 0.

Just before the ground impact Just watch this video of a looping gone bad during a flight display.

At 1:30 into the video it becomes painfully obvious by how much both can diverge in extreme situations (shown above).

The flight path angle is the difference between pitch attitude and angle of attack.

If pitch attitude and angle of attack would be equal, the airplane could only fly straight ahead at the same altitude.

Once it climbs, it has to increase pitch attitude at constant angle of attack.

With enough thrust or speed, both can be 90° apart.

Now consider flying inverted: Both are almost 180° apart.

In a dive, again the difference will become large because the flight path angle takes on negative values.

The more fun

it makes to fly an aircraft, the more both angles diverge.

Only boring aircraft will keep both of them at similar, low values.

How much the pitch (horizontal orientation) can differ from the angle of attack?

270 degrees appears to be the maximum angle that the pitch attitude can differ from the angle-of-attack.

Some examples of extreme differences between pitch attitude and angle-of-attack: Jet fighter or aerobatic airplane or aerobatic glider in a prolonged vertical climb.

(May be a steady-state situation or the aircraft may even be gaining airspeed or it may just be a "zoom" climb where airspeed is exchanged for altitude; obviously only the latter is possible with the glider.)

For simplicity assume a symmetrical airfoil.

Pitch attitude is 90 degrees, angle-of-attack is zero degrees, for a difference of 90 degrees.

Now the throttle (if present) is pulled back to drop the engine power to zero, but the nose is kept pointing straight up until the aircraft starts to tailslide backwards.

Pitch attitude is still 90 degrees, but angle-of-attack is now 180 degrees, for a difference of 90 degrees.

Now imagine the tailsliding aircraft experiences a slight variation in angle-of-attack-- perhaps due to a horizontal wind gust striking the aircraft-- that changes the direction of the relative airflow by one degree, so that the relative airflow is aimed slightly toward the top surface of the wing, rather than aimed directly at the trailing edge.

Now the angle-of-attack has changed from 180 degrees (which also could be called minus 180 degrees) to minus 179 degrees.

Now the difference between angle-of-attack and pitch attitude is 269 degrees.

Flat spin with flight path approximating a vertical descent.

Angle-of-attack may be close to 90 degrees, but pitch attitude may be close to zero degrees.

Actually on the retreating wing it would seem the angle-of-attack may go beyond 90 degrees (wing actually moving backwards relative to the airmass, so the local airflow comes partly from behind), in which case the difference between angle-of-attack of that wing, and pitch attitude of the aircraft, would also go beyond 90 degrees.

Question: How much the pitch (horizontal orientation) can differ from the angle of attack? I am trying to understand the claim that "angle of attack indicator was unfortunately not available", contributing to problems during Air France  Flight 447 .  Attitude indicator  most likely was available?

Can the pitch be very different from the angle of attack?

The angle of attack is the angle between the wing and the direction of travel. The angle of pitch is the angle between the main body axis and the horizon. They can be different.

The angle of attack is the angle between the wing and direction of travel, whereas angle of pitch is the angle between the main body axis and the horizon. They are and can be different. Furthermore 270 degrees seems to be the maximum angle that the pitch can differ from the angle of attack.

Users suggest ways in which they can be different and give definitions


The answer depends on what kind of aircraft you're talking about, and how much control the crew has over the pressurization systems.

For example, in theory you could very well reduce or completely shut off the air to the cabin on a 777 .

This could also be done by a single crew member alone.

The pilots have full control of this system should say the one of the engines produce bad air to that cabin and would needed to be switched off.

As for the oxygen masks-

these are for emergency descent use and have a generator that runs out after about 15 minutes.

The crew bottles last a bit longer I think, but these will also have a limit, and doing any attempt to break through the bullet-proof cockpit door in those conditions I'd imagine would be very difficult, since I'm not sure you're still picking up the amount of oxygen you normally would.

For a similar situation (though not a deliberate attempt) you can read up on Helios Airways Flight 522 .

For an idea of how the pilot masks look, see this video .

Source: SmartCockpit

Yes, I think it would be very easy for the pilot in command of a 777 to do this — here's one scenario: Ask the copilot to get a glass of water and lock the cockpit door behind him Don and activate the oxygen mask

Close the engine

bleed air valves that supply

cabin pressure Open the controlled outflow valves to equalize cabin pressure to altitude pressure

Put the passenger/supernumerary oxygen to "reset" (or pull the circuit breaker)

Ascend a little bit above the service ceiling of FL 410.

At FL 450, consciousness is measured in seconds, death in about 4 or 5 minutes.

Very simple operation

and you don't need to be at 41,000 feet to do it.

Anything above about 21,000 feet

and you die in a few minutes; you just fall asleep.

If you are really paying attention, you would first notice your fingernails (under them) will turn blue due to a lack of oxygen first.

A few giggles perhaps

, then you'd pass out and DIE.

Quite painlessly actually.

The answer is yes: if one of the pilots needed to use the restroom, regulations require the other pilot to put on his O2 mask while the other pilot is away.

Once outside the cockpit, the other pilot could lock the door and the other pilot out.

Then he could turn everything off.

Also since it was at about 1:30am, most passengers would be trying to sleep in their chairs; additionally the masks that drop only have enough O2 to last while the aircraft descends to a lower/safer altitude — so if the plane maintained altitude, there would only be 5-10 minutes of O2 and everyone would pass out and eventually die.

Unless it landed on smooth water, like the miracle on the Hudson, the plane's ELT (Emergency Locator Transmitter) would go off and the crash site would be pinpointed by satellites within seconds.

So therefore one of two things happened:

It landed on water softly and is now at bottom of ocean, or; It landed safely on land because there was no ELT signal.

Depressurization leads not only to the lack of oxygen in the cabin (and cockpit), but likewise may lead to a dramatic drop in temperature.

For altitudes above 38,000 - 65,000 feet, the outside temperature is roughly -70°F/-55°C.

Combined with data suggesting that at 40,000 feet a passenger sitting quietly would retain consciousness for only about 18 seconds with the loss of oxygen from depressurization (and thus presumably fewer seconds at 45,000 feet), it may only be a matter of seconds, not minutes, before everyone in the cabin would be dead.

What I don't know and wish I did know is whether the cabin and cockpit have separate pressurization systems.

I assume so.

This would make it even easier for a pilot to incapacitate/kill all crew and passengers.

Question: Could a pilot of an airliner incapacitate everyone outside the cockpit by somehow triggering a loss of cabin pressure while simultaneously disarming the airplane's oxygen masks, manipulating the air circulation system to induce hypoxia, or some other means?  For example, would it be a credible theory that the pilot de-pressurized the 777 flying  Malaysia Airlines Flight 370  and flew it off somewhere?

Could a pilot incapacitate other crew/passengers by manipulating cabin air quality/pressure?

The pilots have full control of this system. Should one of the engines produce bad air to that cabin and need to be switched off. if one of the pilots needed to use the restroom, regulations require the other pilot to put on his O2 mask while the other pilot is away.

While it is a bit more complicated, it seems that a pilot can actually mess with the systems that control the air in a cabun but only if there is a way to secure himself.

It is suggested that the pilot can manipulate the functioning of the systems that regulate the oxygen.


There have only been a few aircraft built with forward-swept wings.

Most notably was the X-29, which you have pictured above.

Russia/USSR built one more recently in 1997, the Sukhoi Su-47.

One of the biggest claims as to the superiority or an advantage of a forward-swept wing was increased maneuverability.

However, in the case of the X-29, as noted in the Flying Qualities Evaluation of the X-29A Research Aircraft , The high pitch instability of the airframe led to wide predictions of extreme maneuverability.

This perception has held up in the years following the end of flight tests.

Air Force tests did not support this expectation.

For the flight control system to keep the whole system stable, the ability to initiate a maneuver easily needed to be moderated.

This was programmed into the flight control system to preserve the ability to stop the pitching rotation and keep the aircraft from departing out of control.

As a result, the whole system as flown (with the flight control system in the loop as well) could not be characterized as having any special increased agility.

It was concluded that the X-29 could have had increased agility if it had faster control surface actuators and/or larger control surfaces.

The Su-47 was indeed a highly maneuverable aircraft, capable of pulling 9 Gs, however, its immediate predecessor, the Sukhoi Su-37, was capable of pulling 10 Gs .

So it's not clear whether a forward swept wing has any real positive impact on maneuverability.

However, stall characteristics are very different.

Air tends to travel towards the rearmost end of the wing.

On a standard configuration (Rear-swept wing), this of course moves from the wing root to the wingtip.

On a forward-swept wing, however, this moves from the wingtip to the wing root.

As a result, the dangerous tip stall condition of a backwards-swept design becomes a safer and more controllable root stall on a forward swept design.

This allows full aileron control despite loss of lift, and also means that drag-inducing leading edge slots or other devices are not required.

With the air flowing inwards, wingtip vortices and the accompanying drag are reduced, instead the fuselage acts as a very large wing fence and, since wings are generally larger at the root, this improves lift allowing a smaller wing.

As a result maneuverability is improved, especially at high angles of attack.

At transonic speeds, shockwaves build up first at the root rather than the tip, again helping to ensure effective aileron control.

Because of the capability of the X-29 to have the tips of its wings bend down when at high angles of attack, the X-29 remained controllable at an angle of attack of 67 degrees.

However, thanks to modern advances in thrust vectoring, the F-22 Raptor is capable of sustaining an angle of attack over 60 degrees.

With inherent instability and problems with extra stresses on the airplane for only moderate or supposed but not observed gains in instability, it is unlikely we will see combat aircraft with forward swept wings any time in the near future.

Other technologies have enabled similar or enhanced performance without the need for novel concepts.

Advantages: The wing spar carry-through can be placed aft of the cabin, so cabin height can be increased.

This is important for business-jet sized aircraft.

The boundary layer at the tips is not affected by the inner wing.

Controllability can be maintained up to stall.

Aeroelastic effects will increase control commands.

This makes for a very responsive airframe.

However, they are directly connected to these disadvantages: Stall will happen inboard first, which will result in a pitch-up.

If the tail cannot compensate, the stall is unrecoverable.

The aeroelastic effects will encourage flutter.

If flutter speed is found to be too low, the wing needs to be made stiffer, resulting in a weight increase.

These two disadvantages easily outweigh the advantages for most designs.

The first forward swept design, the Junkers 287 , needed a massive, wrought wing carry-through for stiffness.

Handling was great, but performance overall was poor.

Ju-287 with tufted wings and rockets below the wing engines.

The tripod ahead of the vertical holds a faired camera for in-flight observation of the tufts.

(picture source )

If combined with a T-tail, the aft position of the root of a forward swept wing will ensure that the tail is in the wake of the wing root at a high angle of attack, which can result in a deep stall .

The best forward-swept wings can be found in nature: Birds will sweep their wing tips forward if they want to pitch up and create lots of lift.

Especially for short landings the forward-swept wing is ideal when the legs are on the ground at the time of wing stall.

For a text book overview: http://www.desktop.aero/appliedaero/potential3d/FSW.html Note that the Hansa Jet actually was a production airliner using the forward swept wing, and 2 glider types that i regulalrly flew also had forward swept wings (for visibility reasons: Schleicher Ka7 and Ka13). R.

Also Zlin 142 has forward swept wing.

Not for aerodynamic reasons, but to place the pilots at the center of gravity and the spar behind them.

Blanik L-13 and Scheibe Bergfalke sailplanes had swept-forward wings, it seems it helps in adding freedom in setting center of gravity respect to the pressure center and pilots placement.

Advantages of forward swept wings may be mainly in the low speed range, takeoff and landing.

I'm not too sure about Ju-287 being a failure, there are reports it reached 1'000 km/ h in the Soviet hands, good for a bomber, but developing the concept was discontinued, they may have found some heavy problems.

A tailless US airplane of the late 40s used this arrangement, NASA/ NACA, Cranfield repository has documents about it, also YouTube videos exist

Question: What are the advantages of a forward-swept wing vs. a rearward swept one? Image credit: NASA  Image credit:  Paul Maritz  / Wikimedia

What are the advantages of a forward-swept wing over a rearward-swept wing?

A froward-swept wing gives increased maneuverability and the wing spar carry-through can be placed aft of the cabin, so cabin height can be increased.

The mentioned advantages of a forward-swept wing architecture are freedom in setting the center of gravity and the increased cabin height.

Some advantages  are stated, regarding the application of the building architectures.


Can a large modern jet airliner plunge intact underwater from flight?

No.

Large airliners are not desgned for this and are not even strong enough to make a landing on water in less than perfect conditions.

E.g. 961 striking the surface at a larger angle would certainly lead to widespread disintegration.

Is it possible for a large modern jet airliner to sink intact?

Yes (as near as makes no difference)

Almost all large aircraft impacting the sea surface in an emergency or uncontrolled will break up immediately and catastrophically.

One notable exception was US1549 , an A320, which was landed on water without breaking up.

It was described as "still virtually intact though partially submerged and slowly sinking".

The left engine detached and sank.

So a controlled landing on water is possible under extremely favourable circumstances.

It would then be possible for the aircraft to sink in more-or-less one piece without creating a large amount of floating debris.

Hitting water at speed is a lot like hitting concrete (try experimenting with different positions hitting the water off a high diving board—some will hurt).

Aircraft are simply not designed to withstand the sudden forces introduced upon impact with water, no matter the angle.

If an aircraft were to hit the water at high speed, the relatively flimsy structures of the aircraft would shatter, disintegrate, and completely lose structural integrity.

My answer is: It depends.

As always.

Generally, yes, it is possible to land an aircraft on water intact.

But the aircraft has to help you with that.

If the engines are not below the wings (turboprop, piston, jet at the rear fuselage), and the pilot flares to minimum speed right above the water, gear up , then most aircraft will stay intact.

Many are even tested for ditching qualities during development.

I personally know of the ditching tests of the Breguet Atlantique and the Antonov-70, and there are certainly more (see https://www.youtube.com/watch?v=jK8ydLY5QHQ at 2:15 min into the movie).

A Dutch Atlantique once had to go down and landed intact in the North Sea.

It was towed into a harbor and lifted out of the water a few days later.

The openings (for cooling air etc) have special valves which close automatically when the aircraft is in the water, much like a snorkel on a submarine (sorry, could not find a web source for this).

It would be judged upon the state of the aircraft once stopped after the collision, taking into account velocity and angle of impact etc.

If the A/C is in-tact and no water is taken on-board it will float for a greater time

but I highly doubt it will for a large amount of time because water always finds entry points.

If the plane flew to empty, and the pilot made a manual controlled glide and water landing, he would still strike the water at a speed in excess of 150 mph.

The engines would still be ripped off, baggage hold doors would most likely open on impact.

There would have to be some kind of debris field.

The plane would sink, but not intact.

Something would come free and float to the surface.

Question: Is it possible that a commercial airliner could hit the ocean surface at such an angle that it made a deep dive intact, got filled with water, sank, and got stuck in mud at the floor of the ocean?

Can a commercial airliner sink to the bottom of the ocean?

There is disagreement about whether an aircraft can land intact on water or not. Some believe the relatively flimsy structure would shatter and disintegrate while others think it is possible if the aircraft hot the water at minimum speed and as long as the engines are not below the wings.

It depends. With the right conditions, it is possible to land an aircraft intact on water. If an aircraft hits the water at high speed, it will not remain intact.


I have both US and Australian PPLs, and having flown VFR in both countries, there are some real differences in the VFR charts and supplemental data available.

Mostly the contents are fairly evident but if you are unfamiliar with a specific type of VFR chart, it is important to look over the chart in detail to make sure you understand it.

The US publishes VFR charts known as Sectionals .

These cover the entire country, including non-continental areas like Hawaii.

IMHO these are excellent although in busy airspace, the 1:500,000 scale can become complex.

So pilots learning to fly in the US usually become familiar with the sectional covering their base field, and then with that understanding, can look at sectionals for anywhere else in the US.

Printed sectionals can also be used for long range VFR flight planning as they can be laid out in sequence and routes plotted across adjoining chart boundaries.

For online chart examination, SkyVector publishes all US sectionals online, which is a great resource.

Australia does not publish sectionals covering the whole country.

It's a good question as to why but essentially the centre of the country is a big desert where few people live.

So from a historical perspective, the inner part of the country has been regarded as "remote" and thus less in need of highly detailed maps.

In addition, the word 'sectional' isn't even in Australian pilot lexicon, so use the word 'chart' instead.

Australia publishes Visual Terminal Charts ( VTC ) for each large metropolitan area which are a Mercator projection at 1:250,000.

And there are Visual Navigational Charts ( VNC ) which mostly encapsulate the VTCs and are at 1:500,000 (same as sectionals).

The image below is an example of the Brisbane VTC.

As VTC/VNCs cover only largely populated areas, for printed chart long VFR route planning, you will need to revert to the World Aeronautical Charts ( WACs )

, pronounced 'whacks'.

WACs started as an ICAO project after WW2 to transition from the existing US-based international wartime series and so all Allied nations were effectively asked to harmonize their maps with a US design.

But in 2015, the FAA stopped WAC production and thus a recently US-trained VFR PPL would never have heard of them(!)

The US WAC coverage looked like this: WACs are a Lambert projection at 1:1,000,000 and in Australia, printed chart VFR route planning would be done over sequential WAC's, with likely a supplemental VNC chart for the populated areas to be crossed.

WAC's do not contain airspace (although supposedly an aeronautical chart!).

They are essentially a topo map with features that are easy to spot from the air.

So, to answer the OP's question - no

, there are no free online sources for Australian government produced charts.

SkyVector shows a very data sparse US Sectional-like view of Australia

but I wouldn't use it for anything other than simple distance/leg planning.

However, all of the previously mentioned chart types for Australia are now encapsulated and adjoined in a single app known as OzRunways.

I have no association with them, other than being a customer.

Another answer has also referred to this as well.

OzRunways works on both iOS and Android and

in my experience seems very widely used amongst Australian VFR pilots.

For VFR use, they provide a so-called 'Hybrid VFR Map' which simply uses the most detailed chart available.

Price at time of writing is about AUD $100 and chart-wise also has New Zealand and Papua New Guinea.

But also of value to pilots flying in Australia, there is comprehensive airfield information available in the ERSA (EnRoute Supplement Australia), which is a free download .

It lists technical aspects/refueling contacts/etc.

for every sizeable airfield in Australia.

In addition to this, AOPA also publish a pilot guide for various airfields.

OzRunways contains the ERSA and for an extra amount, they also will bundle the pilot's guide.

I would value any other comments about VFR chart sources for Australia but hopefully this is a good overview.

Airservices Australia now publishes electronic versions for free.

Use requires acceptance of an agreement.

Access as follows: Click Publications on the Air Services Australia website.

Click Aeronautical Information Products – (AIP) at the top.

Accept the agreement Select an AIP Charts option on the subsequent page.

Flyermaps provides Australian VFR charts .

I believe OzRunways.com have a VFR package, but it seems to be just for i-devices at the moment.

Australia only produces 1:1,000,000 WAC charts for the whole country.

The more detailed 1:500,000 VNC charts like we have in Canada are available only around major cities.

The VNC chart is similar to the US "sectional" chart.

VNCs are available from Air Services Australia, the state-owned entity responsible for airspace management and aeronautical information.

Question: Are there any sites similar to  SkyVector  (US-based) for GA aviation maps in Australia?   I understand that Air Services Australia has miscellaneous single-purposes  maps available , but they seem to be mostly airport diagrams and approach procedures. I'm looking for GA VFR maps.  If the only thing available is SkyVector's world maps ( of Australia ), how accurate are they?

Where can I find GA VFR maps for Australia?

Austalia does not publish sectionals covering the whole country rather it publishes VTC for large metropolitan areas. SkyVector shows only very sparse data. However, there are no free online sources for Australian government produced charts. ERSA provides a free download and Flyemaps provides Australian VFR charts.

No free online sources exist for charts published by the Australian government. There are no sectionals covering the whole of Australia. Visual terminal charts and visual navigational charts only cover largely populated areas. SkyVector shows a view of Australia that is similar to a US sectional chart, but the data is limited. The ERSA  (EnRoute Supplement Australia) is available as a free download and is useful for pilots who are flying in Australia, as it contains extensive airfield information. The ERSA is also available from OzRunways, which will also bundle it with the pilot's guide. Australian VFR charts are available from Flyermaps and OzRunways has a VFR package. However, this is currently only available for i-devices. The WAC charts for the whole of Australia are only available in 1:1,000,000.

There are no sectionals covering the whole of Australia. Visual terminal charts and visual navigational charts cover largely populated areas.


Well, most airlines do cross the ocean with GPS in today's world.

That being said, most (if not all) transcontinental airliners, and many flying domestic routes as well, have what's called an inertial navigation system (a form of dead-reckoning where gyros and accelerometers are used to compute changes in position).

The INS feeds into the flight management computer which is used to cross-check the GPS position, and can be used as a primary navigation source should the GPS signal be lost or corrupted.

Prior to GPS, inertial navigation was the primary means of navigating across oceans.

However, a great many airplanes did cross oceans before INS... with varying success.

The general idea was to use a combination of dead-reckoning, radio beacons where you can find them (small islands and coastlines), the sun (with the help of a sextant ) during the day, and the stars at night.

Hopefully, this puts you in position after some period of time to pickup ground-based navigational aids, or to identify a coastline.

This actually works pretty well if your wind estimates are good, and the margin for error is high enough.

As DeltaLima points out, long-range radio navigation systems also started to emerge around World War II (LORAN and Decca) which had a much greater range than previous radio beacons, and therefore decreased the amount of time required to fly by dead-reckoning alone.

By the time inertial navigation became prevalent in the 1970's, airlines were already providing reliable transcontinental passenger flights every day.

Another possible outcome is that your plane is lost in the ocean, never found, and the Discovery Channel funds an expedition to look for you 75 years later.

We were crossing the seas centuries before GPS, INS or really any other form of modern technology.

All you need is a clock, a compass and a sextant.

And some largely-forgotten skills, like how to do math without a smartphone.

In the days before GPS, we routinely crossed the oceans using inertial navigation systems.

The system I was familiar with used 3 separate inertial systems (Carousel was the brand name).

You could choose to navigate by any single one, but the most common way of using them was to have the autopilot "average" the positions.

You could also choose to exclude any given INS, in which case if you were averaging, you were averaging only two.

For the North Atlantic MNPS airspace system, You manually updated each INS passing over your last known ground position fix.

When you passed over your first ground-based nav fix on the other side, you again manually updated the INSes with that information and then recorded in the maintenance log how far off left or right

each INS was in the maintenance log.

There were standards.

Offhand

I'm not sure I am remembering them correctly, but what I seem to recall was a max error of 2 nautical miles per hour flown without update.

The MNPS had at the time a max error allowed without penalty of 10 nautical miles left or right of course.

If that was exceeded, points were deducted from your company's score.

Lose enough points and the company would not be allowed in fly in MNPS.

Off course errors of two to six nautical miles for a crossing were typical.

There is the story, true or not I do not know, of the captain who, when hand held GPSs first became available, used one to cross the North Atlantic, and had a near zero off course error.

When ATC complimented him on that, he blurted out that he had used his hand-held.

He was subsequently violated for using a non-approved navigational system.

Whether the incident really happened, I don't know, but an airline's FAA approved op specs specifies not only which navigation methods are to be used but also which systems by brand and model name (at least back when I was flying).

Most aircraft cross the atlantic by GPS, usually with INS as backup.

INS as the primary form of navigation is still used as well.

Historically, a combination of dead reckoning and long range radio navigation systems were used on transatlantic routes.

These include Decca , LORAN C and Omega .

Omega was shut down in 1997,

Decca in 2000 and LORAN C ceased in 2010.

They do use GPS, with backups, as the other answers describe.

If your question is inspired by MH370, remember that GPS tells you where you are: it doesn't tell anyone else where you are.

GPS works by having a bunch of satellites sending out signals and, based on the signals you hear, you can calculate your own position.

A GPS user doesn't transmit anything back to the satellites.

What MH370 lacked was a system that was reporting its location back to base.

Mode of air navigation I've witnessed: Celestial - sextant and charts.

Like, no kidding, right out of days of sailing ships.

Atmospheric pressure - driving along specific barometric pressure lines.

By no means a primary form of navigation.

Omega - now obsolete.

Triangulates on a small number of very powerful radio transmitters spread around the globe.

At least good enough to hit the ADIZ w/in limits.

I'm told when particularly close to a transmitter it can be as accurate as A Cat 2 ILS beam.

Inertial Nav - GPS.

what's that?

Question: How do airliners cross the ocean without GPS?  Do they use dead-reckoning or are there navigation aids floating out there?

How do airliners cross the ocean without GPS?

To cross the ocean without GPS only a clock, compass and sextant are needed. In the past, a combination of dead reckoning and long range radio navigation were used. The INS is now used and it feeds into the flight management computer, it can be used as a primary navigation form without GPS.

Methods of crossing the ocean without GPS include INS; a clock, compass and sextant; celestial navigation; atmospheric pressure. In the past, dead reckoning and long-range radio navigation were combined and used for transatlantic routes.

INS can still be used as the primary form of navigation.

A clock, compass and sextant can be used or celestial navigation can be used with a sextant and charts.


The following statement has just been released today by the Prime Minister of Malaysia, in relation to the AAIB: This evening I was briefed by representatives from the UK Air Accidents Investigation Branch (AAIB).

They informed me that Inmarsat, the UK company that provided the satellite data which indicated the northern and southern corridors, has been performing further calculations on the data.

Using a type of analysis never before used in an investigation of this sort, they have been able to shed more light on MH370's flight path.

Based on their new analysis, Inmarsat and the AAIB have concluded that MH370 flew along the southern corridor, and that its last position was in the middle of the Indian Ocean, west of Perth.

This is a remote location, far from any possible landing sites.

It is therefore with deep sadness and regret that I must inform you that, according to this new data, flight MH370 ended in the southern Indian Ocean.

We will be holding a press conference tomorrow with further details.

In the meantime, we wanted to inform you of this new development at the earliest opportunity.

We share this information out of a commitment to openness and respect for the families, two principles which have guided this investigation.

Malaysia Airlines have already spoken to the families of the passengers and crew to inform them of this development.

For them, the past few weeks have been heartbreaking; I know this news must be harder still.

I urge the media to respect their privacy, and to allow them the space they need at this difficult time.

It's not a "new technology" per se, but a new form of analysis.

You might have heard recently that the aircraft responded to hourly "pings" from a satellite:

British satellite company Inmarsat immediately began doing calculations based on a series of hourly "pings," as the plane and one of the company's satellites tried to communicate with each other.

Triangulating those pings seems to have given Inmarsat a pretty good idea of where the plane went, along one of two routes, to the north and to the south.

Here is

some further information : About three hours after Flight MH370 went missing, Inmarsat, a British-based satellite company, began tracking the Boeing 777 through an on-board data system called Aero Classic .

Every hour, Inmarsat's satellites would try to communicate with the aircraft, pinging it with a computerized question asking, in effect, "Are you there?"

For several hours, Flight MH370 responded "Yes, I am," notifying engineers on the ground with a so-called handshake that the plane was still powered up.

Using that series of pings, Inmarsat engineers and other analysts were able to piece together two broad, arcing regions where the plane could have been located when it last communicated with the satellite.

"Our engineers looked at the time between the handshakes, and they realized that the object wasn't stationary under a satellite but moving away from it," Christopher McLaughlin, senior vice president of Inmarsat, said Thursday.

"Over time, the engineers here recognized that there were a number of data points and that it had flown for several hours.

We didn’t know if it was on the northern or southern corridor."

More information on how Inmarsat determined MH370 flew along the Southern corridor specifically, will likely be released tomorrow at the press conference (as mentioned in Najib Razak's statement), which I gather is the information you're looking for.

Like most geostationary satellites, Inmarsat 3-F1 is not in a truly fixed orbit relative to the earth: it drifts a few degrees north and south.

Knowing this, and more importantly the speed it is drifting north or south, lets them refine their already very good doppler measurements - if you assume the northern path, you have to assume MH370 had constantly varying airspeed - if you assume the southern route, the airspeed comes out constant.

Apparently the satellite is not exactly geostationary but describes a small 8 figure over a roughly 24 hour cycle, and it is known which direction it is moving towards at any given time.

I think it is in fact the Doppler effect of the combined satellite+plane movement which allowed them to distinguish between the north and the south paths.

So, for instance, if the satellite was moving north at a given time one would expect an increased red shift if the plane was flying south and a reduced one if flying north.

CNN replay of the analysis showed that the south route had the plane approaching the satellite like a train approaching an observer then moving away from the satellite for the rest of that route.

The doppler shift therefore resulted in a higher frequency initially then a lower frequency as the plane traveled south.

If the plane had went north the doppler shift would only cause the frequency to get lower and lower much like the sound of a train traveling only away from an observer.

I assume they could also take into account the slight figure 8 that the satellite takes from the 64.5 degree nominal position.

Also they indicated they calibrated the data to known past flights by 777's going south vs north.

From what I can deduce they compared the redshift of the pings to other aircraft flying the proposed routes and were able to eliminate the north hypothesis.

The plane wasn't flying along that arc.

At the moment in time that the ping was evaluated, the plane had to be somewhere on that arc.

They never said it maintained an equidistance from the satellite.

That would be bizarre.

Question: I saw on news that the AAIB helped to locate the missing MH370 flight, saying that it ended up in Indian Ocean, with the help of a whole new technology.  I was wondering what kind of "new technology" it was?

How did the AAIB assist in locating MH370?

AAIB is not new technology but a new form of analysis. A British satellite started tracking flight MH370 after it went missing. The satellite is not stationary and it seems it was a combination of the satellite and plane movement that allowed them to distinguish the path taken.

It is a new form of analysis that was used rather than a new technology. Around three hours after the aircarft went missing, a British satellite company started tracking it using Aero Classic - an on-board data system. Instead of being geostationary, the satellite moves in a figure of eight over a period of 24 hours. It is the Doppler effect of the satellite and the plane movement in combination that made it possible to distinguish between the Northern and Southern paths.


FAA Advisory Circular (AC) 150/5300-13A covers "standards and recommendations for airport design.

" It does not include any restrictions on proximity to bodies of water, but it does make the following recommendation in paragraph 319(a):

It is recommended that the entire RSA and RPZ be accessible to rescue and fire-fighting vehicles such that no part of the RSA or RPZ is more than 330 feet (100 m) from either an all-weather road or a paved operational surface.

Where an airport is adjacent to a body of water where access by rescue personnel from airport property is desirable, it is recommended that boat launch ramps with appropriate access roads be provided.

The actual FARs ( 14 CFR 139, Certification and Operations: Land Airports ) also do not state a limit.

The only reference to bodies of water of any kind is in §139.325 (Airport emergency plan) paragraph (e): The plan required by this section shall contain provisions, to the extent practicable, for the rescue of aircraft accident victims from significant bodies of water or marsh lands adjacent to the airport which are crossed by the approach and departure flight paths of air carriers.

A body of water or marsh land is significant if the area exceeds one-quarter square mile and cannot be traversed by conventional land rescue vehicles.

To the extent practicable, the plan shall provide for rescue vehicles with a combined capacity for handling the maximum number of persons that can be carried on board the largest air carrier aircraft that the airport reasonably can be expected to serve.

So, bottom line: there is no limit, but airports are required to take water into due consideration when developing emergency plans, and the FAA looks at each airport and plan on a case-by-case basis during airport certification.

As for the rest of the world, I have no authoritative information; but as others have posted, it certainly seems like the situation is the same, there being numerous examples of airports worldwide built on natural or reclaimed land very close to water.

There is no such limit indeed.

Princess Juliana International Airport in Sint Maarten is possibly the most iconic example of airport located near a water body, because of the beach over which airliners fly when approaching RWY 09.

As other mentioned, they are numerous other examples of airports that may be even closer to a water body (i.e. without a beach in between).

image source

Water is not an obstacle.

There are plenty of examples around the world where runways are built on purpose-reclaimed land and the ocean starts just a handful of meters from the end of the runway.

For some random examples, check Nice-Côte d'Azur or Gibraltar or St. Maarten.

aviation.stackexchange.com/users/959/hmakholm left over Monica

Runway 28L and 28R at KSFO , as well as 19L and 19R, have their thresholds right next to the San Francisco Bay.

If you recall, in July 2013, Asiana Airlines Flight 214 landed short due to pilot error.

In November 1968, Japan Airlines Flight 2 completely missed the runway and landed in San Francisco Bay.

Not going by Barra Airport - Barra Airport is famous for its beauty - boasting beaches, machair and hills - and all in a small island; Barra is a special place to visit - especially memorable if you fly in because of the beach landing strip.

Washed by the tide twice a day, Traigh Mhor beach is reputed to be the only beach runway in the world to handle scheduled airline services .

See Barra Airport website

The answer to the question is yes, there are limits.

I'll expand for ICAO regulated airports, but this is also true for FAA ones.

ICAO defines an area surrounding a runway, called runway strip, which purpose is to: a) to reduce the risk of damage to aircraft running off a runway; andb) to protect aircraft flying over it during take-off or landing operations.

A water runway strip would not reduce the risk of damage to aircraft running off a runway.

It would in fact increase it, so a runway strip cannot be made of water.

The size of the runway strip depends on the type of runway, but it ranges 150 m to 0m (zero) in width, and it must extend 30 to 60 m beyond each end of the runway (or the end of the stopways, if there are any).

So, the runway strip contains at least the runway (and its stopways) and extends beyond it on its ends, and sometimes (depending on the type of runway)

it also extends to the sides of the runway, and it defines the limits to how close a runway can be to water.

Going even further, ICAO defines a Runway End Safety Area (RESA) for some types of runways which further increases the minimum distance of water to the runway.

Airports such as Sint Marteen, where the runway is almost 190m from the water, are just examples of how the runway strip and the RESA are applied as safety measures against aircraft running off a runway.

Here is Albert Whitted Airport , a GA facility in St. Petersburg, FL, which has actually juts out into Tampa Bay.

Question: Somtimes planes can either  come up short  or  overrun  a runway, ending up in the water.  Is there some limit for how close a runway can be to the water? Does it factor into the runway safety area that is required to be clear of obstacles (i.e., is water an obstacle)? Is there any requirement for displaced thresholds near water?  I am asking primarily about the US, but information about any other jurisdictions is welcome.

Is there a limit of how close a runway can be to the water?

There seems to be some difference in opinion about whether regulations exist relating to the building of airports near water. There is concensus on the fact that the presence of water has to be taken into consideration when emergency plans, etc. are made. Many airports are built near water, including runways at San Francisco airportor even on reclaimed land.

There is disagreement as to whether there are limits. One opinion is that there are limits and the other is that there are no limits, but that airports have to take account of nearby water when drawing up emergency plans. When certifying airtports, the FAA looks at each airport and each plan individually. Barra Airport is cited as an example of an airport where there does not seem to be any limit. Water is not an obstacle. There are lots of examples where the runway ends very close to the water. There are runways in San Francisco that have their thresholds very close to San Francisco Bay. Barra Airport has a beach landing strip.

There is disagreement as to whether there are limits. One opinion is that there are limits and the other is that there are no limits, but airports have to take account of any nearby water when they are drawing up their emergency plans. When certifying airtports, the FAA looks at each airport and each plan individually. Barra Airport is cited as an example of an airport where there does not seem to be any limit.

Although there is no limit, airports have to take account of nearby water when drawing up emergency plans. When certifying airtports, the FAA looks at each airport and each plan individually.


The primary reason is probably that it ensures there is no confusion between passengers, crew, or infants.

Technically, "passengers" is the number of seats occupied, "crew" is both the pilots and flight attendants on duty.

So any small children brought on as "lap children" will not be included in the "passengers" count, but should be included in the total number of people on board.

I found another interesting point over on the English Stack Exchange site , which is that dead bodies are sometimes transported as well.

In this case, some might consider these "people" as well.

Also, in an incident, the bodies should not be confused with the regular passengers.

So, "souls" effectively communicates the number of living humans on board.

There may certainly be holdovers from the maritime influences on aviation as well.

I agree with what fooot said .

Also, I would add, as someone to volunteers in search & rescue (Civil Air Patrol) as a mission pilot, when you hear the word "souls," it adds some urgency and seriousness to the handling of any emergency.

When an air traffic controller asks a pilot, during an emergency, for the number of souls on board, it communicates to the pilot that the controller and pilot are focusing extra hard together on solving the emergency successfully, and that one word tells the pilot that the controller is going to be marshalling resources to help in every way possible.

"Souls" is a term full of life and caring.

For rescuers, it communicates very quickly the total number of persons who must be found and saved.

The earliest reference I can find to 'souls' as a count of persons is mid-eighteenth century, although it probably was in use earlier.

It appears in maritime commerce, as the number of living humans aboard a ship, and in civics, as the population of a town or city.

I think that in the early 1700s the words 'people' and 'person' both had strong connotations compared to those words today. '

People' meant humans of a certain country or a specific culture, and 'persons' meant humans of note or important characters.

So I conclude that a need arose, driven by government and commerce, for a word to mean an unaffected and precise head count, that yet afforded those being counted a little more respect than the barrels, boxes, coins, and cows whose numbers were also tallied.

Now if I could find a reference to that usage of 'souls' from the thirteenth or fourteenth century, I would simply assume that it arose from the learned churchmen who were doing the counting, as literacy was not yet widespread.

The term Soul appears many times throughout scripture, Hebrew translation of this particular use and meaning is literally "breather.

" Some are on the right track with anatomical heart as this is what is required to circulate oxygen.

This also clarifies why transporting deceased persons are not counted among SOB.

They are no longer breathing.

Aircraft (and previously, ships or trains) are frequently used to transport casketed remains en route to funeral.

"Souls" was devised to remove any ambiguity about which "passengers" were among the living.

The term "soul" once meant a whole person: body and spirit.

Thanks to Hollywood's love affair with the word, most now believe it means spirit.

The sad result of this is several phrases now have a different meaning than the historical writings that contain them once intended. "not one soul was saved" - everyone died, now means they are all dammed "bless his soul " - may he have a long life (literally blessing the integrity of the body and spirit), now means bless his spirit "soul mate" - a person physically and spiritually matched, now means a single special someone that is primarily a match of the spirit "he sold his soul" - he has given his life to evil, now means a state of evil that primarily affects the after life "bare one's soul" - to share the intimate details of once physical and spiritual life, now means to reveal primarily emotional details as a stand-in for spiritual things "rest his soul"

- implying that sleep is symbolic of death, now solely a blessing on the spirit "lost soul" - a person not doing well physically and spiritually in this life, now means a person not following spiritual paths

It used to be "souls on board", but was frequently abbrievated to 'sob's", which somehow didn't sound right.

It is now "persons on board"; but there's a lot of momentum in the aviation business and "souls on board" is still used by many

Question: Why don't they just say 'people' on board, why souls? What is the origin of this term? I'm thinking it comes from sailing as I think I've heard that term in reference to crews out at sea, but I'm not a sailor so I don't know.

Why is the total count of people on a plane given as the number of 'souls' on board?

The use of the word souls is probably a hangover from maritime practice. It seems to be used to avoid confusion between passengers, crew and infants. However, it may also be used to instil a sense of urgency in emergency proceedings. Soul is a term used throughout the scriptures and literally means "breather" in Hebrew.

The term "souls" is used so there is no confusion between passengers, crew and infants. It is also used to ensure there is no confusion with dead bodies, which are sometimes also transported. The earliest reference to the term "souls" to refer to a head count is from the mid-eighteenth century. The term may have a maritime origin. The term "soul" is also used in scripture. It denotes life. When used in scripture, the term translates into Hebrew as "breather".  In an emergency situation, the term "souls" conveys urgency and gravity. When the pilot is asked by the air traffic controller about the number of "souls on board", he/she knows that the situation is being taken seriously and that the air traffic controller will be doing everything possible to work with the pilot to resolve the situation successfully.

Dead bodies are sometimes transported as well.

The earliest reference that was found of the term "souls" to refer to a head count is from the mid-eighteenth century. The term may have a maritime origin. The term "soul" is also used in scripture. The Hebrew translation of the term "soul" in this context is "breather".

The term "souls" denotes life. When used in scripture, the term translates into Hebrew as "breather".


IMDB :

McCall's plane is a demilitarized Douglas A-26 Invader, a type used in WWII.

Since the film was made in 1960, I imagine there were plenty of them around.

(The A-26 was known a the B-26 from 1948 to 1965, according to Wikipedia .

The B-25 is easily distinguished because it has the twin tail.)

Yes.

After World War 2, surplus aircraft were cheap, plentiful, and offered great performance compared to pre-war designs, and many were converted to use as executive transports.

The A-26/B-26 was no exception, being the basis for the On Mark Marksman series.

Some of the On Mark conversions involved pretty serious modifications like a new wing spar carrythrough and a new (and much uglier) cockpit.

The B-25, to my knowledge, had no comparable program carried out, but many became water bombers for use in fighting forest fires.

There were undoubtedly some executive conversions made as well!

Other types like the Lockheed Hudson/Ventura/Lodestar transports and patrol aircraft were also popular conversion choices.

The aircraft is a modified Douglas A-26 Invader.

As mentioned in an earlier reply there were several companies which undertook such work.

Most well known was On-Mark Engineering of Van Nuys, CA.

The 26 in question, N36B was one of several (at least two used the same reg.)

owned by citrus tycoon Willis (Bill) Bailard of Santa Barbara, CA.

He had at least three of them over the years.

Possibly four.

Including an unpressurized On-Mark Marketeer.

This example does not have the ring- spar mod as later versions did, and I suspect that it is an earlier Grand Central exec.

version.

Note also in the movie that the 26 still has the fittings for the upper turret installed.

Here is a list of surviving B-25 which may provide some references.

It looks like Redbull has one that they fly around (arguably for business reasons)

I remember Air Spray Ltd., at Red Deer, Alberta, had a highly modified A26 bought from the Mexican government that used to fly around call girls as the interior of the plane had a fully plush white shag carpet everywhere and you could fully stretch out with your hostess.

It also had curtained windows in the back area and a bed type platform in the sealed bomb-bay area.

It also had an extra long nose cone with a small kneeling shower stall that had heated water pumped from a water tank in the nose section.

Just enough for rinsing off.

The A26 outside color was white with a nose to tail medium blue stripe half way up and Mexican registration.

Question: In the movie  Cash McCall , the main character, McCall, owns an aircraft that looks remarkably similar to a B-25 or B-26, but is painted yellow and has no turrets.  Have these aircraft been converted for private business use or were there business aircraft based on the design of WWII bombers?

Have B-25's and B-26's been converted for private business use?

B-25 and B-26 were converted for civilian use after WW2, as seen in the film Cash McCall, because they offered better performance than pre-war planes. Some were even used for transporting call girls. The aircraft in the film is an A-26 Invader.

Yes, these aircraft have been converted for business use. After World War 2, there were lots of them, they were cheap and they performed very well compared to pre-war designs. Many of them were converted for business transport use. The company Air Spray Ltd. purchased a highly modified A26 from the Mexican government. It was used to transport call girls. The aircraft in the film is a modified Douglas A-26 Invader.