Lots of people flew before the Wright Brothers.

Some of them even survived!

The Wright Brothers are credited as inventors of the airplane not because they flew, but because they were the first to take flight in a vehicle which: Lifted itself using its own power (which gliders and kites did not)

Was aerodynamically controllable by the pilot (which Ader's aircraft was not)

Remained in sustained flight, rather than taking momentary flight before returning to Earth

In a way, he did.

But he had little control about all axes.

Derisory comments even suggested he only took to the air thanks to his bumpy runway.

But there were plenty more before him.

The first flying objects which anticipated the airplane were the models of Alphonse Pénaud .

He finished the Planophore in 1871 and influenced all who came after him.

Unfortunately, at his time there was no energy source to power a man-carrying aircraft, and his models used rubber bands for storing energy.

Please note that he did not forget to add a vertical tail

; his design did not need it - the tail-mounted propeller stabilized it well enough.

The next big step was made by Otto Lilienthal , and again the lacking power source restricted him, in his case to man-carrying gliders.

He saw the airplane as a piece of sporting equipment, like a racing bicycle, and priced them accordingly.

He sold over a dozen of them to people all over the world.

And he was the first to use systematic scientific research: He found out that a thick, blunt leading edge and wing camber help to improve L/D.

The polar plot has its name from him.

He experimented with carbon acid engines, but never used a propeller, flapping the wing tips of one of his designs instead.

He also invented wing twisting long before the Wrights, and shared his results freely with the aviation pioneers of his time.

The Wright Brothers built their success on the basis of his work, and were much more secretive.

If we mention Clement Ader, we also need to include Hiram Maxim and maybe even Samuel P. Langley .

They ( and a few more ) all tried to create powered aircraft, but did not get it all right.

At least, Langley's assistant Manly and S. Balzer gave the world the radial engine.

The next pioneer would be Gustav Weißkopf (or Gustave Whitehead ) who seemed to have flown a plane which took a lot of inspiration from Lilienthal's designs, but added a boat-like fuselage and wheels, so he had his hands free for steering the plane.

Lilienthal had put himself into a tight corner by foot-launching his gliders and needing his hands to hold them.

Whitehead flew in 1901, but discontinued his work to focus on his family.

But he was the prime address of his time for airplane engines; many of the early pioneers bought his engines.

Only now the Wrights contributed their part, and are known as the inventors of the airplane due to a contract Orville made with the Smithsonian: The Smithsonian got the 1903 Flyer, but needs to present the Wrights as the sole inventors of the aircraft.

Orville knew exactly how weak this claim was, so he insisted on this clause.

Meanwhile, in Europe, a number of pioneers achieved also powered , controlled flight without using the Wright's knowledge, because Orville and Wilbur kept their findings under tight wraps and started suing everyone who would also attempt to take to the air.

But at the Le Mans flight meeting of 1908 the Wrights showed off their more maneuverable design, shaming all European designers.

How little lasting effect they had in the end becomes clear when you look at the airplanes that followed : The inspiration clearly came from others.

The Langley machine was a disaster, despite its advanced Manly radial engine.

Langley had given almost no serious thought to the problems of stability and control.

But the Smithsonian shot itself in the foot when it hired Glenn Curtiss to "make a few adjustments" in order to make that machine fly.

And Curtiss was indeed sorta successful a decade later, giving rise to the Smithsonian's claim of priority (and a "successful" use of the $50K of taxpayer money Langley had spent!)

It was this skullduggery which enraged Orville Wright and led to his shipping his Flyer to London.

It was only after WWII that the Smithsonian mended its ways with Orville, documenting all the extensive modifications Curtiss had made to the Langley machine, that Orville consented to the return of the 1903 Flyer.

The 1897 plane of Clement Ader has never left the ground , see: General Mensier's Report Clement Ader did not fly.

The October 21, 1897 report made by general MENSIER and its annex from October 27, 1897 (see the link) are clear, Ader’s plane never left the ground with its front wheels in both the October 12 and 14, 1897 officially witnessed tests.

The October 14, 1897 alleged take off and short flight is a pure myth contradicted by historical documents.

Was Clement Ader an aviation pioneer?

Yes, because he built a plane in 1897.

Was he a flyer?

No.

Did he fly earlier in 1890?

No.

The 1897

(Avion III) plane was seen on the ground by General Mensier and his comision.

Other earlier planes (Avion I and II), Ader claimed he had built, has never been seen in the air or on the ground.

Montgolfier brothers were the first to invent a flying machine...

But if you are looking for piloted, controlled, heavier-than-air, sustained, flight the Wrights were the first one to do that

(their longest flight on December 17, 1903, was 852 feet).

Ader didn't really have control or sustained flight.

Objections that the Wrights tried to keep their invention under wraps are noted--and sustained.

Early on, Santos-Dumont did much more for the science and art of flying in the mind of the public, but he was not the first.

Whitehead spun some great yarns but never flew a powered airplane (as vociferous as Whitehead's boosters are, the proof for any powered flights is thin and poorly substantiated).

Question: Clement Ader invented in the late 1890s, a plane that looked like a bat. It had a steam engine. Witnesses said it went airborne at least once and recorded a distance just over 50 meters. The Wright brothers made their first controlled flight in 1903.

Did Clement Ader make the first flight even before the Wright brothers?

Lots of people flew before the Wright brothers, however, Clement Ader was not one of them. Reports show that Ader's plane never left the ground.

Lots of people are known to have flown before the Wright brothers. According to a report by General Mensier, Clement Ader's 1897 plane did not take off. Historical documents indicate that the plane did not take off or fly. Other sources indicate that Ader did not achieve control or sustained flight.

Lots of people flew before the Wright brothers.


Yes, commercial airplanes have landed or crash landed in water many times.

If I am not mistaken, you are asking about scenarios when the on-board life jackets and life raft are used.

Here is a list of water landings.

Examples when a life raft was used are (in addition to ratchet freak's mentions ): On 22 October 1962, a Northwest Airlines DC-7C with 7 crew and 95 passengers made a successful water landing in Sitka Sound. ...

The plane stayed afloat for 24 minutes after coming to rest in the water, giving the occupants ample time to evacuate into life-rafts.

In 1993, China Airlines Flight 605 , a Boeing 747–409, ended up in water after it overran runway 13 ...

All of the 396 occupants donned life-vests, boarded the eight slide/rafts and no fatalities resulted.

Yes - it happened in 2009 in the Hudson (well it's a river), and it happened in 1996 Ethiopian Airlines Flight 961 as far as I know.

Yes.

A Cathay Pacific DC-4 (technically a C-54) was shot down by Chinese fighters off the coast of Hainan island on 23 July 1954.

With his rudder and right aileron shot off, fuel tanks on fire, and the #4 engine down, the pilot ditched into the ocean.

Of the 19 people on board (including 3 flight crew and 3 cabin crew,) 9 died either from bullets or the ditching into the ocean.

The remaining 10 floated in the water for a while and then inflated and boarded one of the rafts.

The passengers remained on board the raft for several hours until a USAF SA-16 Albatross flying boat was finally able to find a spot were it could land on the rough seas, then taxied to the raft and pulled everyone on board before taking off and flying to Hong Kong.

A passenger who had been badly injured died en route to Hong Kong.

The remaining 9 people survived.

Yes there have been several such instances.

To name a few, some of which were captured on camera: Ethiopian Airlines Flight 961.

You can see the actual crash landing video here .

125 of the 175 passengers and crew on board died.

US Airways flight 1549.

The video was caught on a cctv video .

All passengers and crew were safe.

Tuninter Flight 1153.

23 out of 39 survived.

No film exists but it was dramatized in a Mayday episode here .

There have been many other evacuations, some successful and some not so successful.

You can get a detailed list here .

I'm not sure if this fits in with "commercial airline", but there was also a Cessna 208 "Grand Caravan" that crashed just off the coast of Kalaupapa, Molokai, Hawaii about a year ago on December 11, 2013.

It made an emergency landing into the Pacific Ocean after the engine failed just after take off.

The aircraft was chartered by Makani Kai Air to deliver passengers from Kalaupapa to Honolulu .

One person (a state health department director) was killed in the crash.

The crash was also captured on video with a GoPro camera by one of the passengers.

One more for you: an SAS DC-8 crash landed in Santa Monica bay in January of 1969.

Most of the crew and passengers survived, using the on-board life rafts.

There were some issues as two of the rafts were punctured by debris.

The survivors (30 out of 45 aboard) were rescued after about an hour.

The cause was controlled flight into terrain resulting from flight crew failures and a series of issues including an inoperative nose gear light which distracted the crew.

The tail struck first and broke off, sinking immediately.

My dad had been a purser for the airline in the late 1940s

and I remember him telling me that one of the victims sitting in the crew seats in the tail was an old friend with whom he had flown.

My dad was pretty upset to lose a friend this way.

ALM Antillean Airlines Flight 980 was a flight scheduled to fly from John F. Kennedy International Airport in New York City to Princess Juliana International Airport in St. Maarten, Netherlands Antilles, on 2 May 1970.

After several unsuccessful landing attempts, the aircraft's fuel was exhausted and it made a forced water landing (ditching) in the Caribbean Sea 48 km (30 miles) off St. Croix, with 23 fatalities and 40 survivors.

The accident is one of a small number of intentional water ditchings of jet airliners

Pan am flight 6 often mistakenly called flight 943 crashed in the Pacific Ocean half way between Honolulu and San Francisco.

All 24 passengers and 7 crew members were rescued by the coast guard and survived.

The crew members on the pontchartrain are true heroes.

My father was on of them.

The incident happened October 15th 1956.

They lost 2 of their 4 engines around 3:00 a.m. they flew circles to burn off fuel and wait for daylight.

They hit the water at 8:15

a.m.. the plane split in half but Coasties were there within minutes.

Question: They have rafts and life jackets on board and before takeoff, passengers are explained how to use that equipment, but have any evacuations ever happened successfully?

Has a commercial airliner ever crash-landed in an ocean?

Commercial airplanes have landed or crash landed in water many times.  It happened in  2009 in the Hudson  (well it's a river), and it happened in 1996  Ethiopian Airlines Flight 961. A  Cathay Pacific DC-4 (technically a C-54) was shot down by Chinese fighters  off the coast of Hainan island on 23 July 1954. Pan am flight 6 often mistakenly called flight 943 crashed in the Pacific Ocean half way between Honolulu and San Francisco.

There have been multiple instances of commercial aircraft landing or crash-landing on water. Examples include the 1996  Ethiopian Airlines Flight 961, a SAS DC-8 in Santa Monica bay in 1969 and Pan Am flight 6 in the Pacific Ocean. A Cathay Pacific DC-4 was also shot down by Chinese fighters in 1954 and a Cessna 208 "Grand Caravan"  crashed close to Hawaii in 2013.


A couple of my CFIs have asked me to help them park the airplane (in absence of a tow bar) when I was pushing the airplane by putting one hand on the hub and the other on the propeller near the hub, and them (the CFIs) pushing the tail down and nose wheel elevated.

But according to AOPA , it is not a good thing: ... never push or pull on the prop blades.

Forget what anyone has told you about pulling near the hub or the strength of the propeller.

Aluminum blades can bend, and it doesn’t take much to put the blades out of track with one another.

This PDF says the same thing: Avoid pulling the airplane around by the prop.

Yes, this seems the perfect solution to a vexing problem of how to change the airplane’s position without having to walk around and get the tow bar, but it’s worthwhile to make the extra effort.

Neither the engine nor the prop particularly benefit from the loads imposed by horsing the whole airplane around.

Classic example of one corner case leading to a blanket belief.

Grabbing a propeller by the tip, especially a wooden prop, can cause damage.

In use, the tips generate most of the thrust but are also held straight by the rotational forces.

Pulling on a prop right beside the hub will cause no harm -

that's where the propellor thrust goes anyway.

If you grab the prop on both sides the airframe won't know that the engine isn't running.

So, here's a Rule of Thumb: if you cannot touch the prop hub with your thumb while pulling on the prop, you are holding it too far out.

Well, grabbing the propeller at the blade root and pulling from there cannot hurt it.

Why?

Because the thrust imparted by the propeller to the aircraft is applied at exactly the same place.

In other words, the propeller pulls the airplane through the air at the hub.

You are so close to the hub that you're not going to create a significant bending moment along the blade.

On the other hand grabbing the propeller at the tips would be questionable at best, and ill-advised!

I asked around at my gliding club about this, the consensus seems to be that it won't harm the plane as long as I didn't use excessive force.

The reason for doing it is to not have to walk from wing to wing to move the plane.

The main counterpoint is that you shouldn't move a plane by yourself unless you're very sure you won't hit anything (another plane, the hangar walls, etc).

By deviating from the standard procedure (using the tow bar) you incur into the following risks:

Mechanical damage: you risk damaging propeller itself if you don't pull from as close as possible to the hub.

Furthermore, being more complex, variable pitch blades obviously imply more risk.

Arguably, the forces in play during taxiing are similar to those exerted manually through pulling.

Also, in my flight school, during pre-flight inspection we actually perform some push/pulls to assess that the propeller, hub, and drive are ok -- suggesting that there is no mechanical stress derived from doing so.

Safety risks: although arguably rare, you may accidentally start the engine through hand-swinging.

I was instructed in my flight school to shut down the engine through the mixture control mainly to prevent this from happening during the pre-flight inspection previously described.

This is also why we perform magneto ground checks during shutdown.

As always with these questions it seems to be a religious thing.

If you ask 2 people you will have at least 3 different answers and most of them will sound somewhat reasonable.

I had the situation that my FIs always taught and asked me to move the planes (taildraggers) with me pulling the plane on the prop and them steering using the rudder.

A few days ago another guy walked up to me when I moved the plane shouting at me

"NEVER do this

, you'll destroy the prop"So I called the technical support of the specific airplane (Diamond Aircraft) and asked them.

TL;DR:

Manufacturer says that's exactly the way they move the planes in production when they don't have the tow bar around.

For reference: The plane has an electric constant speed prop

so I guess about the most fragile you can find in terms of prop.

Of course you should always grab as close to the spinner as possible One can verify plane specifically this from POH or AMM, for example Diamond DA 62

AMM states:

I know this thread is 4 years old

but I could not find the questions answered anywhere else

and the question comes up on a regular basis esp.

in clubs where "knowledge" is passed on from member to member.

How do you taxi your plane?

I use my engine to spin my propeller, which pulls on the hub and pulls my plane hard enough to make it roll on the ground.

On takeoff, I do this so hard that the 2000+ lb plane rolls 60 knots or so before it leaves the ground.

Now, with that in mind, do you think pulling on the prop, close to the hub, enough to move the plane 10 feet is doing any damage?

Question: It's very common to see pilots moving a light aircraft by pushing or pulling on the prop, either because there's no tow bar available or simply out of preference or convenience. Is this a reasonable thing to do or can it damage the prop or engine in some way?

Is it OK to move a light aircraft by pushing or pulling the propeller?

It seems that moving a small plane using the prop is unlikely to cause damage as long as too much force is not used.

There are two differing opinions on this. One is that the loads resulting from moving the aircraft in this way are not beneficial. The other is that this will not harm the plan, provided that the force used is not excessive.


In most common passenger aircraft brakes are automatically applied when the gear is retracted.

The wheels stop spinning before they enter the wheel well.

This is particularly important because a spinning damaged tire may cause damage to hydraulic and fuel lines which are usually routed near the wheel bay.

The nose wheels have no brakes, so they are spinning while they are being retracted.

Most aircraft have rubber brake pads (snubbers) fitted in the nose gear bay that stop the spinning of the gear once the wheels are retracted.

The question was formulated in the context of a jet liner such as the Boeing 737-800 or the Airbus, I do not understand why there are persons responding to this question in the context of a smaller less complex aircraft.

With that being said, I will like to expand the answer by DeltaLima.

Boeing uses a device attached to the Brake Metering Valve Module called a De-spin Actuator.

This device directs controlled hydraulic fluid to the brakes when the landing gear lever is set to retract to stop the spinning of the wheels.

More information can be found in the AMM ATA 32 (Aircraft Maintenance Manual Chapter on Landing Gear).

https://www.facebook.com/aviationisawesome/videos/1598830786833154/ Video of a 737-500 from inside the main gear wheel

well shows: After becoming airborne, the landing gear suspension unloads and the wheel hangs down, still spinning

Once the main gear arms begin retracting, the wheel stops within a second

The gear has fulled retracted in 6-7 seconds.

De-Spin Actuator Source: http://www.eaton.com/ecm/groups/public/@pub/@eaton/@aero/documents/content/ct_194202.pdf

These are the "nose wheel spin brake linings" (the braking pads) that stop the spinning of the nose wheel after retraction.

I fly retracts and have heard this question a dozen times.

Some people say to tap the brakes, other people (like me) never do.

I have asked certified mechanics, and they have all said it doesn't matter.

My advice is to follow the POH.

If it says tap the brakes, then do so.

Otherwise do or don't it doesn't matter.

General policy when operating a retractable gear aircraft is to apply brake pressure after becoming airborne and prior to commanding the retraction of the landing gear.

This causes the wheel to cease spinning, removing gyroscopic precession loads on the landing gear during retraction (remember a spinning tire acts like a big gyroscope and wants to maintain its orientation in space) as well as reduces the chances of damaging components inside the wheel well when the gear is stowed.

Follow the POH is always the best and most correct answer because it is different on different models and types.

I have a 1971 C177RG POH in front of me right now

and it says:

Landing Gear RetractionBefore retracting the landing gear, the brakes should be applied momentarily to stop wheel rotation

On the 737, the main gear gets gear retract braking pressure when the gear lever is placed in the UP position.

It also doesn't hurt that a heavy brake stack will close up under gravity as the wheels are turned horizontal during retract.

The nose wheels are free to spin up into the wheel well, where they contact a friction brake that drags on the tires; slowing and stopping nose wheel spin.

Question: What happens to the spinning landing gear right after V 2  on takeoff? Are they automatically or manually braked to a halt before gear retraction? Or are they allowed to spin to a halt in the wheel wells?  I am asking this question in the context of common passenger planes, such as the Boeing 737-800 or the Airbus A320.

What happens to the spinning wheels of the landing gear after takeoff, before retraction?

Generally wheels stop spinning before they are retracted. The general policy is to brake the wheels before retracting. However, nose wheels have no brakes so they are spinning as they retract. There is a device in the nose gear bay that stops the spinning.

Brakes are usually applied automatically when the gear is retracted. Brake pressure is usually applied after take-off and before retraction. Although the wheels stop spinning before entering the wheel well, the nose wheels do not have brakes so they are still spinning during retraction. Boeing planes have a device called a De-spin Actuator. Having said all that, the best answer is to check in the POH because it will vary for different models and types.

In most common passenger planes, the brakes are applied automatically when the gear is retracted. The general policy is to apply brake pressure after take-off before ordering the retraction.

Although the wheels stop spinning before entering the wheel well, the nose wheels do not have brakes so they are still spinning during retraction. Most planes have brake pads in the nose gear bay that stop the gear from spinning after the wheels are retracted.

Boeing planes have a device called a De-spin Actuator attached to the Brake Metering Valve Module.

The best answer is to check in the POH because it will vary for different models and types.


If the controlling software allows it then yes.

There's at least one drone available where autonomous flight is possible ; the Vision 2 FAQ says that the drone will continue its "mission" even if you lose the signal to it, although the overall length of the flight path is limited to 5km and the drone will not fly close to airports.

Other drones stop and hover or land if they lose the connection to the controller.

Whether doing this is actually a good idea (or legal in

whichever jurisdiction you want to operate in) or not is a whole other question.

In general, unmanned flight control systems operate in one of two main modes: manual control and program .

(There are other modes but these are typically specific situations, such as launch/landing sequences, loss of link (aka "return home"), and any other design-specific operating modes as required (see below).

To answer your question, if link is lost while the aircraft is in manual operation, a good flight system will automatically go into "return home" mode, where it flies to a pre-programmed GPS coordinate and altitude.

Some software will allow you to customize the sequence, such as whether or not to spiral up to altitude before heading to that coordinate.

Other software will backtrace the route it took.

Aircraft following a pre-programmed route typically change to manual mode upon completion, hoping there's a good ground link at the other end.

In military operations, this is known as a "hand-off" where one ground station takes control from another.

One Shadow flight I was running lost link immediately after launch.

After completing its autolaunch sequence, it went to return home and circled for hours until it ran out of fuel, at which point the engine stalled and the generator (alternator) hiccuped in transition to battery power, causing the flight processor to reboot, at which point we re-acquired link, though too late to do anything about it.

The UAV had already noticed its engine wasn't spinning and initiated its ditch sequence, rolling over and popping the chute.

From a technical standpoint, as other answers pointed out, it is technically feasible.

For instance, universities have attempted a 180 km flight over the Mediterranean sea .

However, there are also legal issues involved when flying a drone beyond the range of the remote control device.

For instance, in France , even when using an autopilot to control a drone, a safety pilot must stand ready to take control of the drone in case anything happens.

The Chicago Convention (1944), article 8 states that No aircraft capable of being flown without a pilot shall be flown without a pilot over the territory of a contracting State without special authorization by that State and in accordance with the terms of such authorization.

Each contracting State undertakes to insure that the flight of such aircraft without a pilot in regions open to civil aircraft shall be so controlled as to obviate danger to civil aircraft.

In many countries, these special authorizations can take a few months (a little more than three months in the case of the 180 km flight over the Mediterranean sea) to obtain, so hobbyists usually don't bother.

Yes, most of the sophisticated consumer drones allow you to pre-program a track into them and can fly totally autonomously.

Also, most of even the less expensive drones (FN1) are designed to return back to their starting GPS coordinates if they lose their control signal.

: Less expensive still means around USD 500 or so.

Sophisticated drones are USD 1000 and up.

From a technical perspective, there's nothing preventing it.

It wouldn't even be very difficult to write the code to do it if you had a GPS receiver on board, especially if you also had accelerometers to interpolate position between GPS fixes.

For that matter, remote control via a cellular network wouldn't be particularly complicated from a technical implementation perspective (and this would also aid in navigation if you triangulate position from the towers.)

Where the problem comes in is legal issues.

Specifically, in the U.S., at least, operating such an unmanned aircraft outside the line-of-sight of the operate is illegal unless you have a special license from the FAA, which is generally only granted to federal government agencies or law enforcement/emergency/rescue organizations or to aircraft R&D organizations.

According to the FAA : Recreational use of airspace by model aircraft is covered by FAA Advisory Circular 91-57 (PDF) , which generally limits operations for hobby and recreation to below 400 feet, away from airports and air traffic, and within sight of the operator.

Federico was right on in his comment in that this is a weak 'answer' and yes, I know better than that.

While not answering the body, this question does answer the one in the title.

See Man detained outside White House for trying to fly drone , as well as related stories of that day, for an example on what not to do with your UAV... As a synopsis,

if I remember the details correctly, a US Federal employee was at a friends house in Washington D.C. and they were playing with the friend's new quad-copter (some might call it a drone).

There was much drinking and celebration and the man was flying the quad while quite drunk.

He flew it towards the White House and it disappeared.

It landed itself on the White House lawn.

So, yes, a 'drone' can fly beyond radio range.

Depends on the programming of the drone - mostly if it contains code for autonomous operations.

Furthermore, it can have a "drone call home" subroutine which would cause it to become "autonomous"

(it isn't fully autonomous, but it can fly on it own in a straight line).

Question: In a hobby drone, is it possible to set up the autopilot so that the drone travels to a distance far beyond the range of the remote control device and then comes back to the starting point? When I see hobbyists flying drones , it seems the drone always hovers within the boundaries of the field.  Is it possible for a drone to reach a friend's house on the other side of town and then come back to the start point?

Can a drone travel beyond the range of its remote control signal?

It is feasible for a drone to continue flying when the signal is lost. It depends on its programming. Good drones have "return home" mode. However, in the US, it is illegal for drones to fly outside the line of sight.

It is technically possible for a drone to travel beyond the range of its remote control signal provided that its programming and software allows for this. However, it is illegal in the USA to fly an unmanned aircraft out of sight of the operator unless you have a special license from the FAA. Model aircraft for recreational use may only be operated below 400 feet, within sight of the operator and away from airports and air traffic.

In the USA, it is illegal to fly an unmanned aircraft out of sight of the operator unless you have a special license from the FAA. Model aircraft for recreational use may only be operated below 400 feet, within sight of the operator and away from airports and air traffic.


It depends on the aircraft, but in general the answer is that there are no regulatory age limitations, and indeed we have many aircraft flying that are 50+ years old.

A notable exception is the Robinson line of piston helicopters.

The airframe on those helis is limited to 2200 hours or 12 years , whichever comes first, at which point the entire airframe must be completely overhauled.

Some of the airframes are indeed rebuilt, but some are also scrapped, depending on level of wear and corrosion.

Since the airframe lifetime is in the LIMITATIONS section of the POH, it is governed by: § 91.9 Civil aircraft flight manual, marking, and placard requirements.

(a) Except as provided in paragraph (d) of this section, no person may operate a civil aircraft without complying with the operating limitations specified in the approved Airplane or Rotorcraft Flight Manual, markings, and placards, or as otherwise prescribed by the certificating authority of the country of registry.

N60094 , a 1909 Bleriot XI based at Rhinebeck Aerodrome Museum, has a valid FAA airworthiness certificate .

So I think it's safe to assume there are no FAA restrictions based solely on age. ]

Aircraft hulls are limited in the wear and tear

they can withstand due to metal fatigue that can develop (pressurized aircraft more than non-pressurized).

The manufacturer will impose limits on the flight time of the hull (an older airframe will be considered not airworthy) so any developing metal fatigue will not tear apart the plane in flight like what happened with the Comet or Aloha Airlines flight 243 .

tl;dr

it's the responsibility of the manufacturer to impose limits on the airframe age.

According to Wikipedia the DC-3 first flew in 1935, entered regular passenger service in 1936, and as of 2012 #10 off the production line was still in regular commercial service.

I'd venture to say it's got more to do with maintenance than regulation.

(I'm sure someone will quote the appropriate FAR section in a few minutes.)

As a general statement aircraft are pretty well-built (in fact, they are generally overbuilt

so they'll hold up to use and abuse in excess of their stated design tolerances), and carefully maintained.

As such there is generally no regulatory restriction on airframe age , though there may be other applicable restrictions (or recommendations) depending on the aircraft.

The most common restriction you'll encounter

that's similar to what you're asking about is what are known as "life-limited parts" - Aircraft components that have a finite limit (expressed in flight hours, flight cycles, or calendar time), after which they must be replaced or overhauled.

These limitations are usually given by the manufacturer (in a Limitations section of the POH/AFM or Maintenance Manual, which has regulatory effect under FAA rules).

In some cases an entire airframe may be life-limited: ( The R22 helicopter has both a calendar and hours limit, and commercial airliners typically have a flight cycle and flight hour limitation on the airframe as well.

In other cases only a component may be life-limited: The wings on a Grumman Tiger or a Piper Tomahawk must be replaced after a certain number of flight hours.

Even in absence of a specific limitation it's important to recognize that all airframes have a finite life - components will eventually suffer fatigue and fail, as with any kind of mechanical equipment.

Manufacturers may recommend extensive inspections of older aircraft to ensure that fatigue is detected before the structure fails.

(For example, while the Piper Cherokee family has no Limitations published Piper does recommend extensive inspections on aircraft that have accumulated a large amount of flight time.)

Question: Is there any restriction by FAA that one can not fly a plane older than 'X' years?  If someone is maintaining an older plane (e.g. from 1990s), are there any regulations which prevents or restricts that person to fly that airplane?  I am interested in finding out both for commercial and smaller general aviation airplanes.

Is there any limit by FAA on the age of aircraft to be operational?

There are no regulations limiting the life of an aircraft. In fact, many very old planes are still flying. However, the manufacturer may impose limitations on flight time for the hull to prevent metal fatigue issues.

Generally speaking, there are no regulatory age restrictions. There are many aircraft over 50 years old that are still flying or still airworthy. Examples include a 1909 Bleriot XI and a DC-3. Whether older planes are still operational is more a question of maintenance than of regulations. For example, manufacturers may set limits in terms of the flight time of the hull or may recommend inspections of older airplanes so that any fatigue can be identified promptly.

Generally speaking, there are no regulatory age restrictions and there are many aircraft still flying that are over 50 years old.


The FAA has an FAQ on bird strikes and other wildlife hazards, which includes a (broken) link to their Wildlife Hazard Management at Airports - A Manual for Airport Personnel document .

Chapter 9 is called "WILDLIFE CONTROL STRATEGIES AND TECHNIQUES AT AIRPORTS" and includes the following techniques: Change flight schedules Modify the birds' habitat (food, cover, water)

Physically exclude the animals (not so easy with birds)

Repel the birds with vehicles, chemicals, sound, visual objects (flags, scarecrows, fake dead animals, lasers)

Repel the birds with trained falcons or dogs Shoot

nonlethal projectiles at the birds Trap, remove and release the birds at a different location Kill the birds with poison or other means

The document summarizes the various techniques like this: Habitat modifications to minimize food, cover, and water and physical barriers to exclude wildlife are the foundations of wildlife hazard management programs for airports.

In addition, an integrated array of repellent techniques is necessary to disrupt normal behavior and to stress hazardous wildlife that attempt to use the airport.

These repellent techniques must be used judiciously and backed by real threats to minimize habituation.

To this end, lethal control of selected individuals of common species is sometimes necessary to reinforce repellent actions.

about.com has a good article which lists the many methods that are used to scare birds away from airports.

It includes: Modify the habitat:

Remove sources of food, such as seed-bearing plants, use insecticides to eliminate insects as a food source, remove bushes and plants that can be used for nesting

The use of visual devices (lasers) or audio (sonic cannons, recordings) to scare away birds Trained falcons, dogs, or other predators to make the airport inhospitable to birds.

Another source: Birds at Airports - Internet Center for Wildlife Damage Management

(Image Source:

WikiMedia Commons - Author: Bluescan sv.wiki )

On a visit to Blackpool Airport control tower a few years ago, they mentioned that they flew a hawk/falcon (not sure which) every day to deter birds

The airport authorities use a number of techniques to manage the hazard of bird strike in and near airports.

These include, Elimination of bird habitats-

Birds usually come to the airport area due to the availability of food sources.

Denial of food to birds by eliminating the sources (like landfills, garbage, crops, dumps etc) will reduce the chance of birdstirke by eliminating the source.

It also helps to keep the airport and surrounding areas unattractive to birds (for example, by eliminating water stagnation, vegetation cover etc) as it prevents the birds from nesting there.

Scaring them away-

A number of airports use a number of bird repellents like pyrotechnics, cannons (mostly just prior to aircraft approach to prevent bird habituation), chemical repellents etc.

In some cases, specially trained animals (like falcons, dogs etc) have been used to scare away the birds or they are trapped.

In some cases, the flight schedule can be altered if bird movement is expected in the area (for example, if the airport is on a bird migration route).

The problem can be solved by simply killing the birds in the area, though this drastic step is usually not implemented except in the most extreme cases.

In general, the nesting sites of birds are destroyed to prevent them from staying permanently near the airport.

Usually, a combination of above methods is used to manage the birds.

The only procedure available for flight crews is to either delay the flight (or land in alternate runway if its available) in case birds are detected over an area.

This however, is dependent on a number of variables like fuel availability, flight schedule etc.

There are some radar systems under development that could detect birds; however, these have not reached operational stage yet.

Trap, kill, harass, or deprive them of food and shelter.

The number of bird strikes at my airport has been reduced dramatically by consistently harassing the birds to the point where the birds eventually adapt and learn.

All the correct information has been added except one point.

The engines nose spinners have a design painted on them.

Once the engines are running the design is suppose to look like the eye of a bird of pray to scare off birds in flight.

Does it work

I can not say

but they claim it does.

Question: I know bird strikes are a major issue for many airports, and that measures are taken to keep birds away. There are some obvious things airports can do like not to have any stray garbage, food, etc. in the open, but I'm sure other less obvious methods are also used.  What exactly are some of the widely used techniques to keep birds away from airports?

What are the ways to keep the birds away from airfields?

A number of approaches are used by airports to keep birds away. These range from using animals and birds of prey to scare birds away to trapping and killing or harrassing them to make them leave the area. Other methods involve destroying their nesting sites or firing canon as planes come in to land. Apparently a radar system that can pick up birds is being developed.

In some cases, animals such as birds of prey or dogs are used to scare the birds. Some airports use repellents such as pyrotechnics, cannons or chemical repellents to deter birds. The birds can be trapped, harassed, deprived of food and shelter or, in the most extreme cases, killed. If birds are detected or expected in an area, the flight schedule can be altered or the aircraft can land on a different available runway. Radar systems that can detect birds are being developed but are not yet operational. Resources relating to this subject include an FAA FAQ and an article on about.com.


As long as an aircraft transmits (unencrypted) ADS-B information, anyone within radio range can track it.

The equipment necessary to receive ADS-B can be as simple as a computer with a TV receiver (USB DVB-T module) and the right software.

Receivers can then send the data stream to, for example, Flightradar24 , who will display it on their website.

As Flightradar24 states, not all aircraft are equipped with an ADS-B transponder, and even those that do may not have switched it on.

Unless ADS-B is installed and operating, it would not be visible.

@ezra-g mentiones that Steve Jobs' aircraft was blocked , but this is of something one would have to ask for, and the site has to apply the filter so it doesn't display on its website.

However, Jobs' plane would still have been visible on the receiving computers.

And, of course, the website will only filter your aircraft if they are willing to do so, either on request, through payment, or a government order.

Flightradar.com also has some other data sources, like FAA (Federal Aviation Administration)

radar information in the US, which also contains aircraft without a transponder.

The FAA may also filter some aircraft.

From the FlightAware FAQ : How does FlightAware handle flights around the world?

What is FlightAware's service area?

FlightAware's primary service area includes airspace operated by the United States (including Alaska, Hawaii, Puerto RIco, and Guam), Canada, the Caribbean, Australia, the United Kingdom, and France.

Flights in the primary service area support real time maps, departure and arrival information, delays, and more.

FlightAware's secondary service covers scheduled major airline operations at any airport in the world.

Flights in the secondary service area support departure and arrival information.

Secondary coverage areas may have real-time positions for ADS-B equipped aircraft operating in FlightAware's ADS-B coverage area.

Additionally, some airlines send FlightAware satellite position reports from aircraft worldwide that augments other position data and provides transoceanic coverage as well.

For flights arriving in a service area from outside of a service area, FlightAware will be able to track the flight when it nears a service area.

For flights departing a service area, FlightAware will be able to track the flight until it leaves the coverage area.

Flights may not be tracked beyond that point unless they enter another service area.

Not all worldwide data sources (e.g., European data, datalink ARINC/SITA ACARS, etc) are freely available on FlightAware.com due to government regulations or commercial arrangements.

You can contact us if you have a commercial need for worldwide data.

Flight tracking websites, such as FlightRadar24 and FlightAware , generally track aircraft using publicly available ADS-B transponder information.

Privately operated aircraft are included as long as the owner of the aircraft has not specifically requested that their aircraft be excluded from public searching.

For example: Steve Jobs' private plane's N-number was public information, but it was excluded from tracking on Flightaware.

Military aircraft are not included in public ADS-B tracking information.

For more on ADS-B and flight tracking, see the information from FlightRadar24 and FlightAware .

Flight-tracking sites can track military aircraft, but generally don't .

For example, I live near a USAF base and can easily track dozens of military flights a day with an ADS-B receiver, but not one of those flights has ever shown up on FlightRadar24.

Yes, recently PlaneFlightTracker provided exactly this live service both for NATO and Russian Military aircrafts as well as Medical, Emergency, Safe and Rescue helicopters and airplanes.

It starts with a procedure explaning how to track as well as Live Military Aircrafts Maps.

This site uses the FlightRadar24 map for embedment but has made an effort to extract necessary ICAO codes so that the users may get the proper maps.

Question: Many flight tracking websites have the data about almost all the commercial airplanes in air. Do they have the data about the private jets and/or defense aircraft also and they just don't show that on the websites?

Do flight tracking websites also track non-commercial and defense aircraft?

Any plane can be tracked if it transmits unenncrypted ADS-B information, including military planes. However, military planes are not included in public ADS-B tracking information.

ADS-B transponder information is publicly available and can be tracked by anyone within radio range. Flight tracking websites generally use this transponder information to track flights. Military aircraft are not included in this public transponder information. Although flight tracking sites are able to track military aircraft, they tend not to. Having said that, PlaneFlight Tracker recently provided this service for NATO aircraft and Russian military aircraft as well as for medical, emergency and rescue aircraft.


Helicopters are also subject to metal fatigue and there have been accidents attributed to it but the primary determination is component life times.

All of the engine, transmission and rotor parts are lifed and most of the control mechanisms.

Depending on the helicopter, there will be many more lifed components.

Some helicopters also have fixed intervals between major overhauls by the manufacturer.

For example, the R22 is effectively rebuilt to an "as new" standard by Robinson at 2,200 hours.

Corrosion might also play a part.

There may be a time when it is just not economical to continue to repair and service the airframe.

I am a Aerospace Systems Engineer and former Royal Air Force.

Although my qualifications and experience are within the avionics arena

I feel I can answer this question: There are basically 3 types of Helicopter and for that fact any aircraft: Military Civil – Private Civil –

Commercial

The military aircraft have the shorter life in terms of flying hours, the Civil Commercial the longest life in terms of flying hours where as the Civil Private / light aircraft have a very long life in terms of years.

A military aircraft can have an airframe file of say 4,000 to 6,000 hours compared to some civil commercial aircraft with an airframe life of 60,000 to even a 100,000 hours.

Now that is for the airframe and ONLY the airframe.

The engines, landing gear and most important in terms of helicopters Gear Boxes, Rotor Heads & Blades all have significantly shorter life.

One example is that I used to work on the RAF Chinook HC1 i.e aircraft as originally delivered to the RAF by Boeing Vertol.

These aircraft where returned to Boeing to be up-graded to the RAF HC2 standard and where returned to the RAF as “New” “Zero Hour” airframes.

So, as I say its not always the airframe but the bits that are bolted on to it.

Now, I worked on the RAF HC1 Chinooks from 1988 to 1991.In April 2018

I went to RAF Odiham on a photography shoot event organised by TimelineEvents.

ComDuring that photoshoot I saw aircraft that I had worked on

whilst I was on 7 Squadron i.e

this particular aircraft must originally been delivered to the RAF in about 1986 making it about 32 years old.

However, I would say that the rotor blades will / must be less than 5 years old.

Again, another however, the Engines (2 off) and gear box’s (5 off)

will of be an indeterminate age but will / must contain a mixture of bits dating from less than 12 months old all the way through to the 32 years age of the original airframe.

I think though the most remarkable aircraft was ZA671.It was delivered to the RAF as a HC1 Chinook and returned and rebuilt by Boeing as a HC2.

It crashed whilst in the USA sustain what the RAF calls Cat 4 damage –

Cat 5 being a write off and Cat 1 being scratched paintwork.

Boeing rebuilt this aircraft as a HC3 Chinook

and it’s the one I worked on and is still flying

and I have to say that seeing the crash report and photos I am surprised that it was not classed as Cat 5 and I really would not have liked to fly in it during its test flight post accident repair.

But the point is that again it depends on what the aircraft is built for, how it's used, how it's maintained, "usefulness”, it's value v. cost of next major servicing.

All of the above will totaled together determine the actual life of an aircraft

Nothing limits the lifespan of a helicopter.

There are many bits and pieces that need to be maintained in order for the helicopter to remain serviceable but so long as there is nothing broken on the helicopter and all overhauled items are within their overhaul limits, and all lifed items are within their life limits... keep on flying.

An Aircrane (Siskorsky S-64)

I used to work on just rolled 20,000 hours total time on her fuselage.

Still going strong.

I don't know of any machine that has a hard airframe time that puts it out of service permanently.

Sorry...

no Commercially manufactured helicopter...

there may be a kit machine that has a limited life.

I am told that the hourly and calendar service life of many military helicopters are established by the OEM.

Under certain circumstances, that can be extended when scheduled "rework events" are accomplished by the manufacturer or a certified facility.

The military uses industrial rework facilities "depots" to ensure many fuselages remain airworthy beyond established service life.

Fatigue is a problem that limits, if not the life of the helicopter, at least the working life of some of its key elements, in particular of those subject to strong vibration and made from materials (such as aluminum alloys) that have a fatigue limit.

Vibration is the main culprit, and it usually comes from the rotors.

In rotary-wing aircraft, vibration can be contained, but never fully eliminated.

Most helicopters will go though some sort of "Phase" of "Depot" inspections where different components will be replaced due to life-span requirements.

For example; a uh-60L will require a shock strut replacement every 1500 flight hours to prevent a collapse of the strut due to over use.

OK - a couple of comments on the Chinook again based on artices from James 360 and Flight International.

The RAF is buying another 16 Chinook's.

I gues

these will be Mrk 7's ?

Any way the on-line articles correctly point out that some of the Aircraft ar over 40 years old !

This is true.

Our 1st Chinooks where built and delivered before the Falklands War which was in 1982 !

On a recent trip to RAF Odiham i say a few aircraft that i had worked on when i was there from Oct 85 to Nov 88.There where also some newer aircrfat.

However, they where all built to the Mk 3/5 stnadard and a few years ago i had the opertunity to see some of the Mk 6 aircraft.

on each rebuild the aircraft are stripped in fact the aircraft rebuilt to the HC2 standard from HC1 where return to the RAF as Zero Hour Airframes (less test flights i hope).

But nothing lasts for ever unless its a brush that has had two new handles and 4 new heads !

p.s

yes I am dyslexic.....

Question: The lifespan of aircraft is generally limited by  metal fatigue . This is true for fixed wing aircraft; is it also true for helicopters? What is the determining factor for helicopter useful life?

What limits the lifespan of helicopters?

Fatigue is a problem that limits, if not the life of the helicopter, at least the working life of some of its key elements, in particular of those subject to strong vibration and made from materials (such as aluminum alloys) that have a fatigue limit. Helicopters are also subject to metal fatigue and there have been accidents attributed to it but the primary determination is component life times.  There are many bits and pieces that need to be maintained in order for the helicopter to remain serviceable but so long as there is nothing broken on the helicopter and all overhauled items are within their overhaul limits, and all lifed items are within their life limits... keep on flying.

Metal fatigue can be a problem for helicopters too. It can affect the working life of certain components and has been thought to cause some accidents. The main determining factor though is the life of the components. Various components may need to be replaced as a result of life-span requirements. However, although components may need to be maintained to keep the helicopter operational, nothing actually limits the life of the helicopter, provided that all components are within their required limits. Some manufacturers set fixed intervals for major overhaul of helicopters. In addition, corrosion may play a part. It has been said that the OEM establishes the service life of many military helicopters.

Metal fatigue can also be a problem for helicopters. It can affect the working life of certain components and has been thought to cause some accidents.

The main determining factor is the life of the components. Various components may need to be replaced as a result of life-span requirements.

Some manufacturers also set fixed intervals for major overhaul of helicopters.

Although components may need to be maintained to keep the helicopter operational, nothing actually limits the life of the helicopter, provided that all components are within their required limits.


Once your engine fails the airplane is the property of the insurance company, your only goal at that point should be to survive.

Using a whole-airframe chute increases your chances of survival whether over land or sea.

The things that kill people in forced landings of any kind are high-g deceleration and post crash fire.

A parachute decreases the chances of both as you have very low lateral speed and much less chance of fuel tank leaks.

A parachute also will increase the chance the airplane will remain upright, so escaping the aircraft will be much easier - very important in a water landing!

The only reason for a "normal" ditching procedure is that you have no other choice, using a parachute if you have one will almost always be the right option.

The only time I would consider otherwise is if I had enough altitude to glide to a safer emergency landing spot.

If pulling the chute would mean landing in water or dangerous terrain but gliding would mean reaching land where a forced landing was reasonable

I'd probably opt for gliding.

First, according to one operating handbook for the Cirrus SR-22 (there are several versions out there), pulling the chute is the correct ditching procedure (CAPS is the parachute system): Ditching Radio ............................................

Transmit (121.5 MHz)

MAYDAY giving location and intentions Transponder........................................................... SQUAWK 7700 CAPS ............................................................................. ACTIVATE Airplane.........................................................................

EVACUATE Flotation Devices ............

INFLATE WHEN CLEAR OF AIRPLANE Second, the conditions were

reported to be windy with high waves:

Weather conditions at the time of the rescue were seas of 9 to 12 feet and winds of 25 to 28 mph.

Those would be tough conditions for ditching in.

I've read several times that when light aircraft ditch, the pilot and passengers usually survive the impact but they often struggle to exit the aircraft successfully.

This article and video explain in detail how difficult it can be to exit an aircraft in the water, even in good conditions.

If the aircraft flips or cartwheels then exiting would be extremely tough and the rough sea would make it much worse.

Since the parachute lowers the aircraft straight down in a more or less level attitude, the chance of flipping over is greatly reduced.

The downside is that you no longer have control of where you touch down relative to the waves, so you might land just in front of one but that still seems like a good option compared to the risk of flipping the aircraft on impact.

Maybe pulling the chute is the normal ditching procedure for a cirrus with an airframe chute.

The splash down looks to be very gentle compared to a normal gliding ditch with fixed gear.

It's also less prone to pilot error; once you are dangling there is not much the pilot can mess up.

I imagine the checklist being something like: pull chute when aircraft stabilizes open door put on life vest and prepare raft should plane roll and sink get out and on the raft

The odds of survival with the chute are currently at 100% (Per Cirrus) and the odds of surviving a ditching are much less.

The plane was lost in the Pacific either way.

The correct thing to do is pull the lever and ride it down, live to be a great pilot another day.

The real question is what did the pilot do wrong to end up in that situation?

The proper response to losing the engine would be to follow the emergency procedures checklist.

In that you will find it says to deploy the ballistic parachute.

While a better option, the ballistic parachute has its own drawbacks.

I recall when getting checked out in a Cirrus years ago by an approved training provider that I was told the impact with chute deployed can be up to 8 G's.

So I would say not 100% survivable.

Actually I know of a Cirrus that went down near Sanford Florida a few years back that deployed the chute and the occupants died.

Question: In  this incident near Hawaii , a Cirrus SR22 had fuel problems and deployed its  airframe parachute .  My question is why did the pilot deploy the parachute rather than perform a "normal" ditching procedure in the ocean?  For reference, here's  the video .

Why did this Cirrus deploy the parachute while ditching over Pacific Ocean?

When the engine fails on a light aircraft the correct thing to do is use the parachute. This gives the pilot a greater chance of survival and als helps to prevent the plane from flipping over. Apparently, many people survive the impact of a light airplane crash but have difficulty getting out of the aircraft when it lands on water.

When light aircraft ditch, the pilot and passengers often struggle to exit the aircraft. A parachute makes it more likely that the aircraft will remain upright rather than flipping over. This makes it much easier to exit the aircraft. The objective in this situation is survival. Using a whole-airframe chute increases the chance of survival compared to ditching. A ditching procedure would only be used if there is no other option. Using a parachute will normally be the right choice and will increase the odds of survival.

A parachute also makes it more likely that the aircraft will remain upright rather than flipping over. This makes it much easier to exit the aircraft.

When light aircraft ditch, the pilot and passengers often struggle to exit the aircraft. Escaping the aircraft is much easier with a parachute landing.


Yes, it has been done before in an even larger aircraft, the Boeing 367-80, very famously by "Tex" Johnston on August 7, 1955 .

This aircraft was the prototype for the Model 707.

When a barrel roll maneuver is properly performed the aircraft remains in a positive-G state, so no "inverted flight" is experienced by the aircraft.

According to the International Aerobatic Club , The Barrel roll is a combination between a loop and a roll.

You complete one loop while completing one roll at the same time.

The flight path during a barrel roll has the shape of a horizontal cork screw.

Imagine a big barrel, with the airplanes wheels rolling along the inside of the barrel in a cork screw path.

During a barrel roll, the pilot always experiences positive Gs.

The maximum is about 2.5 to 3 G.

The minimum about 0.5 G.

Yes, and its happened at least once in a -80 which eventually became the 707.

It became so legendary that rumor has it

Boeing Chief Test Pilot John Cashman stated that just before he piloted the maiden flight of the Boeing 777 on June 12, 1994, his last instructions from then-Boeing President Phil Condit were "No rolls."

Yes, it is possible.

We experienced this possibility using a simulator on a 747/400.You have to take a very high angle at the beginning like 25° nose up to avoid exiting with an important nose down and overspeed.

Of course doing it with passenger is stricly forbiden.

Here is a video of a stolen Q400 Dash-8 doing a barrel roll.

That's not quite as large as a B737, but I think it's close enough for the purposes of the question, especially given it was accomplished by an amateur.

It's fair to assume that a trained pilot could do at least as well in a much larger plane--if they were willing to risk their job/license.

Yes it is possible.

It happen in a Brazilian plane hijack in September 1988 on flight VSP375 from Vasp flight company. .

The plane was a Boeing 737-317 (# 23176, serial #Boeing 1213, Brazilian register PP-SNT).

The hijacker wanted to throw the plane on Brazilian president official home , the pilot tried the maneuver and succeed with 105 passengers onboard.

Question: Can the bigger planes like B737 do barrel rolling kind of stunts like fighter jets do? I'm sure if it's full of passengers or cargo it would be very difficult and dangerous, but is it possible with an empty aircraft?  I remember  an All Nippon Airways incident  where the co-pilot did a 131 deg roll by mistake but I don't know if a complete barrel roll is actually possible in large planes?

Is it possible to do a barrel roll in a large aircraft like a B737?

It is possible for large aircraft to do a barrel roll. It has been done on a number of occasions including during a hijack in Brazil in 1988. It has also been tried in a simulator. Evidently it is strictly forbidden to try this with passengers onboard.

Yes, it is possible and it has happened before - in a Boeing 367-80 in 1955 and in a Brazilian plane that was hijacked in 1988. It has also been performed in a simulator. As you would expect, performing the maneuver with passengers on board is strictly prohibited.

Performing the maneuver with passengers on board is strictly prohibited.


Boarding takes a long time, true.

There are more efficient strategies (.pdf) which have been proven to speed up boarding by between 20% and 50%, still they are not adopted.

Why?

You need to load the baggage, too.

Also the catering.

And fuel.

You need to inspect the aircraft, run through checklists and brief the new crew.

This all takes up time, too.

Airlines do not see a big saving by loading passengers faster, and then waiting for all other jobs to be completed.

Your radical idea of containerizing passenger transport would certainly speed up things, but it would cost a lot of payload.

The most efficient pressure vessel is a sphere, and the next efficient is a cylinder with spherical ends.

Pressurizing a boxy container is structurally very inefficient.

Loading passengers on palettes first and sliding those palettes through a narrow opening takes time in itself.

And the palettes have their own weight, their own floor, their own support structure for the baggage racks, their own cabeling for the entertainment system.

They would, however, not need their independent pressurization, so their weight impact would be moderate.

A possible "flatbed" airliner which could attain the shortest boarding times has only half as much fuselage height (or less) to transmit bending loads along its length.

See here for an example of buckling in a fuselage skin due to bending loads.

Now consider that reducing height by 50% will need four times more cross section in the longerons to keep stiffness constant.

That will make the fuselage much heavier.

In the end, airlines go with the solution which maximizes their profits.

By using a hollow cylinder and let their "cargo" self-load, they can maximize their payload and get tolerable boarding times.

Tolerable for them, that is.

That better loading procedures could allow you to come to the airport later is of no interest to them.

If they would see an advantage in shorter boarding times, there would be ample of opportunity by improving strategies, even with existing airplane designs.

The system you propose would be extremely heavy compared to existing aircraft.

More weight means more fuel and more fuel means even more fuel to carry that fuel through the air, and even more fuel to carry that fuel and so on.

Fuel is one of the biggest expenses an airline faces.

It would also be extremely expensive.

To gain any time, you'd have to have the departing passenger capsule loaded and ready before the arriving passengers have left their capsule.

That means you need twice as many capsules as planes.

And the time saving wouldn't be all that great.

You'd still have to refuel the plane and load and unload the cargo.

Manoeuvring a fuselage-sized capsule into the plane would be a long job.

I'm far from convinced that it would be faster than getting however many hundred people through the door.

The first and biggest concern would be the weight of the container.

They need to have walls, floor and a ceiling and be able to lock in place on the plane.

Also each division between containers would remove some room available for another row of seats in the traditional method.

Passenger crates were envisaged a long time ago.

Apart from the above objections, may I add this: A passenger crate in a plane is a box in a box.

This would worsen claustrophobia which is already a problem.

A view outside would alleviate this, but requires windows.

Crate windows would need to be aligned with fuselage portholes.

The psychological problem is doubled by a physical problem which is emergency evacuation.

Any project would need a highly standardised crate compatible with competing aircraft types.

This standard would later become a constraint for future design innovation.

It would also limit customisation of planes by constructors for specific customers.

I wouldn't want all of the connections for pressurisation, air conditioning, lighting, water, IFE etc etc connected and disconncted every flight.

A maintenance and safety headache.

Something even more radical has been considered!

Airbus filed a patent on replacing the entire upper fuselage - seats, passengers and all - during a layover.

The structural problems inherent in that idea look pretty hard though.

My suspicion is that delays in loading passengers onto aeroplanes come from two sources: 1) Security & border concerns since the hijacking of aircraft became common in the 1970s; 2)

Airports' desire to make money from passengers being forced to wait in airports, where they buy things from retailers who are paying tenants of the airport.

On the topic of (2) a British airport group (Heathrow is one of their properties) told shareholders around 15 years ago that they were not in the transport business, but in the retail business, pointing out that over 60% of their revenues came from rents paid by airport retailers.

It's elementary economics that while this is the case, airports and airlines have no incentive to make aircraft boarding quicker, even if a solution for (1) were found.

Were airports to shift their revenue model away from retail, this entails airlines paying more for landing slots, so the two groups have a common interest in wasting the time of travellers by keeping them in airports for as long as possible out of their travel time.

A saner approach to speeding up the loading of passengers would be - rather than loading them in boxes like freight - to simply cut the airport out and have passengers board special buses in town, check their bags and travel documents with a couple of officials who are also travelling on the bus, and have those buses drive straight onto the tarmac and up to the aeroplane.

This is after all how very rich people travel.

Someone drives them straight to the aeroplane.

Airports earning 60% of revenues from in-airport retail tenants are unlikely to support this simple idea, however.

I for one would jump at the chance to arrive earlier, "board" earlier and sit in cramped airline seating even longer so the airline can save money.

If you didn't pre-load the passengers in your capsules before the plane was ready to depart, there would be no time savings.

No thanks.

It's bad enough they hold you prisoner on the plane when there are hour + long delays in departure.

Question: Apparently, the time for boarding and deboarding an airplane is a large cost factor and something airlines try to minimize but have trouble controlling because the passengers do it themselves.A solution would be to have passengers board a passenger cabin outside of the airplane and then slide that cabin into the plane via a nose-hatch, much like large volume freight. Has this been considered? If yes, why was it not pursued?

Why don't airlines load their passengers like freight?

Loading passengers in the same way as freight is not really advantageous to airlines. It would not be much faster than current boarding times, the container would add a considerable weight to the aircraft and passengers would possibly suffer greater claustrophobia, which is already a problem during flight.

Although this process might speed up boarding, it could also be quite a time-consuming process in its own right. It would also be very expensive and could significantly increase the weight of the aircraft.

Although this concept might speed up the process, it would be very expensive.

This concept in itself would be time-consuming.

The proposed system would be very heavy.


I can relate to you the true story of my uncle who successfully landed a large WWII aircraft with no flight training.

He was the flight surgeon on board a large aircraft that got heavily shot up.

Hostile fire killed or severely injured every crew member.

He moved the pilot out of his seat, and contacted a control tower.

With the expert help of the control tower operators, he successfully landed the aircraft.

After the war, he had a private practice in his home where he saw patients.

For patients too ill to come to him, he performed house calls.

He continued to perform house calls until a short time before he passed.

I have always thought his life story would form a compelling foundation for an inspiring movie.

aviation.stackexchange.com/users/4095/RockPaperLz- Mask it or Casket

Yes.

The question will have subjective answers and this is my opinion.

The basics of flying an airplane doesn't change from a single engine airplane to a big airliner.

The concept of lining up on final, flaring into the touchdown attitude and setting it down is exactly the same.

There are some things that are different; for example, retractible landing gear, leading edge slats, spoilers and thrust reversers.

Many of the differences can be overcome by talking with ATC and an instructor / pilot trained to fly that airplane through the radio.

The biggest challenge would be knowing when to flare as you are sitting much higher in an airliner than in a single engine airplane.

This can be overcome with listening to the radar altimeter and flaring as directed by the instructor.

I'd share a personal experience: a few years ago I got the chance to fly a Boeing 737 simulator (the real thing, not the PC simulator!)

At that time the only real aircraft I've flown was a Cessna 172.

I managed to land on Kai Tak airport in the simulator on my very first attempt to land a (simulated) 737.

I was so nervous that I totally forgot to call for the landing checklist, and the instructor helped me with the gear and flaps, but I was the sole manipulator of the controls

and I landed with no automation whatsoever, not even ILS.

How?

There were a few factors that came into play:

I learnt how planes fly in ground school.

Big planes fly just the same way as smaller planes, only with larger wings and more powerful engines.

I knew how to manipulate the flight controls.

It came as a bit of a surprise that the controls feel heavier than I'd expect, but they behaved the same anyway.

My enthusiasm in aviation meant I have learnt beyond the Cessna 172 from books, online articles and PC simulation experience.

I was not able to identify every single switch and knob in the cockpit, but I knew enough to fly the plane in that situation.

My answer?

If it's a perfectly flyable aircraft (no failures), calm weather, then

Yes, definitely!

Here's what I'd do if it happens in real life: Aviate, navigate, communicate.

No matter what happens, always remember that.

That means the first thing to do after entering the cockpit is not to find the radio buttons and call for help; the first thing is to access all primary flight instruments and make sure we're flying.

Radio for help .

Declare an emergency on the last radio frequency.

If no one responds, tune to 121.5 and try again.

Request a long runway with calm weather.

Unless it's something like a A380 or Boeing 747, chances are there would be a runway long enough

so you don't have to worry about hitting the touchdown spot.

Setup autoland , if available.

Autoland requires suitable equipment both on the plane and on the ground.

If it's not available, given a long enough final (say 20 miles), I think I'd feel comfortable hand flying the aircraft down.

Have the emergency trucks standing by .

In the event I crashed during landing, gear collapsed or whatever, everyone'd be ready to help.

My dad, an experienced pilot, was once given the chance to fly a 727 simulator (full motion, the works).

He stalled it 40 feet over the runway and the simulator came down hard enough on the stops to hurt his back and scramble the gyros.

That's only one data point, but any rate, the crash would have been survivable, so there's that.

Like anything in aviation, it depends, There, to date, have been no documented cases of this happening.

There have been a few "talk down landings" in smaller aircraft with low time or inexperienced pilots.

Similarly there is at least one documented case of an air force B-1B Pilot assisting in landing an airliner

he had no experience flying but

you can argue he had plenty of jet time.

People have tried it in simulators of course but a sim is a sim.

Of course things like cross winds and runway length will play into the success rate of an event like this.

I will say that the margin of error on these things is small and on a calm day

I'm sure it's possible.

I would hesitate to give a hard yes to this question since there are far to many factors to take into account

but I do feel under the correct circumstances it could be done.

On a small side note, since this question is about Quad Engine planes (747, A380 etc) considering the distances those planes typically fly it's more than likely that there is one if not two relief crews on the plane so the chances of everyone becoming incapacitated and requiring a passenger step up to the plate is slim to none.

Question: I'm assuming that almost everyone on this website has seen the movie Airplane at least a few times...  Last time I was watching it I was wondering how plausible the actual act of having a single engine prop pilot, with a lot of training (maybe comparable to a modern day aerobatic pilot), land a quad engine passenger jet?

Could a single engine pilot land a passenger jet? (from Airplane)

Landing a plane of any size is basically the same so a trained pilot could land a jet liner. The biggest challenge would be the position that is much higher in a commercial aircraft. There are no documented cases of such incidents, however.

There are no known cases of this happening. The basic principles of flying an airplane do not change - whether it's a single engine plane or a large airliner. One difference would be that in an airliner, you are sitting higher up so knowing when to flare would be the biggest challenge.

In an airliner, you are sitting higher up so knowing when to flare would be the biggest challenge.

It depends. There are no known cases of this happening.


This stopped after the World Trade Center attacks.

You might be able to get a kid in briefly before the plane takes off.

Generally speaking, you will not get very lucky unless you are a pilot yourself and are carrying your license with you (and even then, this is airline dependent).

If this is the case, you might even be able to ride in the jump seat for a portion of the flight

On the ground a lot of pilots/cabin crew are friendly and would be happy to show you around.

Use common sense though and ask to go after landing for the best chance - before take off the crew will be quite busy with pre-flight checks.

Usually the cockpit is restricted during any phase of flight besides boarding/de boarding.

This is usually the case with major airlines with any destination in Europe, or the U.S., not sure abut Asia though

Can I ask to go to the cockpit during a flight ?

Of course you can.

The answer will be a firm "No" and you will be watched very closely by the cabin crew and any plainclothes security onboard until you land.

It's possible the police will be waiting for you.

Can I ask to go to the cockpit after a flight ?

Of course you can.

If it's a longer stop the crew are often happy to show off their office.

If it's the end of a 12 hour intercontinental flight with a bad-weather landing they might decline.

It's a security and/or safety risk to allow any persons in the cockpit these days.

This accident happened as a pilot allowed his children to take control during flight.

With the autopilot active, Kudrinsky, against regulations, let the children sit at the controls.

I've seen flight crashes, in which persons in the cockpit have interfered with the flight in one way or the other.

Based on these experiences, unauthorized persons in the cockpit is totally not allowed these days.

About 30 years ago I did this during flight when I was a kid.

These days I manage to do it for my daughter but only while boarding.

Question: As a kid, I remember going to the cockpit of a plane with my mom (I believe the airline was  AOM French Airlines ).  Is this still possible now?  I understand the answer might differ with different airlines/countries, I'm mostly interested in European and Asian airlines/countries, specifically Japanese.  Is there some specific regulations for international flights, or does it depends on departure/arrival locations?

Can a passenger request to visit the cockpit during a flight?

Allowing passenegs in the cockpit was stopped after the Wordl Trade Center attacks. Allowing anyone in the cockpit is a security risk, even licenced pilots may or may not be allowed depending on the airline. It may be possible while the plane is on the ground. There have been crashes caused by people in the cockpit.

The main issue here is safety and security. Access to the cockpit is restricted during flights except for boarding and disembarking. The practice of letting people into the cockpit stopped after the World Trade Center attacks. There have been instances of flights crashing as a result of people interfering with the flight while in the cockpit.

When the plane is on the ground, the pilots/crew may be happy to show you around. A child may be able to enter the cockpit briefly before take-off. Most of the time, you are unlikely to be allowed into the cockpit unless you are a pilot carrying your license.


Yes It's true.

And yes it's related to pressure.

Have you heard of "The bends" or decompression sickness ?

As divers go deeper the pressure increases.

The longer you dive and deeper

you go the more nitrogen is absorbed into your blood as a dissolved gas.

As you return to the surface the pressure reduces and the nitrogen reverts to a gas.

This decompression needs to be done slowly so the nitrogen can pass back out through your lungs.

If you ascend too fast the nitrogen can form bubbles in your blood (Just like when you open a bottle of coke.)

which can be painful and possibly fatal.

Even once you have finished diving you will still have residual nitrogen in your blood which will take time to release.

Air pressure reduces further when you fly.

If you finished a dive and got in a plane the rapid climb in altitude would result in a drop in pressure similar to a rapid ascent while diving.

So you would run the risk of getting the bends.

Small planes aren't pressurized.

But even pressurized planes might not maintain atmospheric pressure when flying.

This topic should have been covered if you have taken a dive course.

To add a reference to Peter's answer, from PADI , one of the institutions that releases Scuba diving certificates: Flying after Diving Recommendations For Dives within the No-Decompression Limits Single Dives: A minimum preflight surface interval of 12 hours is suggested.

Repetitive Dives and/or

Multi-Day Dives:

A minimum preflight surface interval of 18 hours is suggested.

For Dives requiring

decompression stops :

A minimum preflight surface interval of greater than 18 hours is suggested.

It's not just blood, but soft tissue generally.

48 hours is extremely conservative - recreational (single tank of air, 40metre maximum depth)

diving guidelines say only 24 hours.

Don't forget

altitude (lakes at > 300metres) diving also affects No-Decompression Limits .

When diving, your body absorbs nitrogen gas.

As you ascend towards the surface, your body releases that gas.

If it is released too quickly, you'll get "The Bends".

Modern dive computers model the body as a series of different tissues: fat, muscle, liver, cartilage, brain/nerves, bone marrow, etc.

Different dive computers will model different tissues, typically between 8 and 20 tissues.

Each of these tissues absorbs, retains, and releases nitrogen at different rates.

The dive computer will track a number of different tissues, but show you only the most critical of the tissues (eg, the one that will take the longest to off-gas to a safe level).

Depending on how long you've spent at various depths, the critical tissue will change.

This is guidance for just returning to the surface safely.

Other factors affect each individuals off-gassing rates, such as BMI, general health, specific metabolism, and alcohol consumption.

When you later fly, you're going to even less pressure, and your tissues will off-gas even more.

If you're flying in a typical pressurized commercial jet, you'll be at around 8,000 ft pressure-altitude.

But if you're in an un-pressurized charter flight, you could easily hit 10,000 - 16,000 feet.

Many people have trouble understanding that a "small" plane will actually hit a higher pressure-altitude at 14,000 feet, than a "big" jet at 30,000 feet.

If you haven't been doing extreme diving, and are flying pressurized, then 24 hours is safe for a normally healthy person.

If you're flying un-pressurized above 10,000ft, then 24 hours may be safe.

But because The Bends depends on many subtle factors and is unpredictable, 48 hours is considered much safer.

This leads to the typical dive planning advice that you should begin with your most aggressive (deepest, longest) dives first, and use your easier dives later in the trip.

Your body can continue to off-gas from your most deepest dive even during your subsequent, shallower dives.

This is a little contrary to human nature, as many people want to begin at an easier level, and get more aggressive with each dive as their comfort level grows.

But that only sets up the body for a high N 2 load, adding more and more with each dive.

If you have any aggravating factors, such as poor health, significant fat (BMI), alcohol consumption, or a prior incident with decompression, then I would avoid the more aggressive dives and plan on as much time as practical before even a pressurized flight.

For many recreational divers, this simply translates to "no diving and no drinking on the last day of a trip:

Just go sightseeing, or stay on

the beach" Credentials : Certified NAUI, PADI, and SSI; Trained Recuse Diver; Experienced with Deep, Night, Dry Suit.

(but mostly retired and above the surface now).

By every recommendation I've ever seen 48hrs is extremely liberal for recreational divers.

I went on my first dive trip with my parents when I was 12 years old and our rule was to quit diving at least 24 hours before your flight.

It is related to pressure and it all depends on how much time you've spent and at what depth.

The deeper you go, the quicker you build nitrogen in your tissues and the more time you'll need to allow for that nitrogen to dissipate.

If you spend enough time at depth there is even a recommendation to make a safety-stop during your dive (typically 5-15 minutes at about 30ft for recreational diving) as a best-effort to avoid the bends and surface decompression.

The U.S. Navy created classification charts that indicate your relative nitrogen absorption.

Here are some resources hosted by NOAA, one of them being a PDF specifically covering this topic. http://www.ndc.noaa.gov/dp_forms.html http://www.ndc.noaa.gov/pdfs/USNDeco3.pdf

Question: Is this rule even true and why is it? I'm going to assume it has to do with pressure but can someone give me a good explanation?

Why must one wait 48 hours to fly, after scuba diving?

It is true that you should not fly within 48 hours of diving. This is a pressure issue. The deeper you dive the more nitrogen is absorbed in the blood and the more time you need to clear it. Going up in a plane and the drop in pressure would be like making a too rapid ascent from a deep dive.

Yes, it's true. This rule relates to pressure and depends on how much time you've spent underwater and at what depth. Nitrogen builds up in your tissues more quickly as you descend deeper underwater. As a result, you need to allow more time for the gas to be released. If you do not leave enough time between finishing a dive and flying, the rapid increase in altitude would lead to a drop in pressure similar to the one experienced if you ascend too quickly from a dive.

This rule relates to pressure and depends on how much time you've spent underwater and at what depth. If you do not leave enough time between finishing a dive and flying, the rapid increase in altitude would lead to a drop in pressure similar to the one experienced if you ascend too quickly from a dive.


Pilot here (with Cessna 152 hours) as well as an engineer who made it most of the way to an Airframe and Powerplant technician license at one point in life.

There are several reasons that conspire to produce 'unusable fuel':

Fuel tanks on airplanes have complex shapes - they include baffles and other walls (with holes in them) to prevent oscillations from building up during in-flight movement.

Sometimes these baffles are even engineered into the tanks late in the design cycle as testing finds oscillation issues.

These baffles result in 'geometric trapping' of fuel in nooks and crannies.

Drawing fuel from a fuel tank is more complicated in a plane - cars

are pretty much flat with minor tilts while airframes can have all sorts of odd and sustained directions that the fuel wants to go due to acceleration.

Imagine an extended tilted spiral while descending - that fuel experiences far more lateral acceleration over a longer time period that a car would have.

Getting the fuel system to pull fuel out from these different angles is challenging (note that I've picked a non-aerobatic maneuver for which the Cessna 152 of your question is qualified here).

All of this is a cost/complexity tradeoff - solutions exist for 1 and 2 above - fighter jets use fuel bladders that have pressure bladders arranged to squeeze the fuel out so that they can get almost all the fuel even at high G-forces and unusual angles.

Aerobatic planes have similarly more expensive and complicated systems than the old and cheap Cessna 152.

There are other considerations as well, but mostly it comes down to whether the plane in question can justify the cost and effort to get every last drop of fuel.

Things get even more complicated in rockets - the moon rockets (properly the Saturn 5 although it was an upper stage specifically) had special extra engines called ullage motors whose only job was to give the stage a little boost in space to push the fuel towards the rear of the rocket so that the main motors could draw fuel and start.

Addendum edit: @supercat below -

the definition of unusable fuel is set by federal aviation regulation part 23, section 959 ( FAR 23.959 ) and basically is the worst case under "intended operation" for the particular plane.

Since the Cessna 152 is not aerobatically rated, for example, the unused fuel is defined as the fuel level where SOME intended maneuver would be capable of causing a fuel system error.

In practice, especially in flat level flight, some of that unusable fuel would be available for use although you are not supposed to plan to use it in your flight planning.

especially since water contamination of fuel is a concern?

That's one of the reasons.

Fuel floats on water, so water collects in the bottom of the tank, along with other gunk.

By not taking the last dregs of fuel from the bottom of the tank you avoid putting this stuff into the engine

Almost any system that moves liquid around will retain a certain volume.

In your case, there are various bends in the pipes and some of those bends go up.

Yes, it's gravity-fed but notice the shutoff valve on the floor.

Now notice the level of the carburetor.

Any fuel below the level of the carb bowl is unusable, as we have no way to push it through the rest of the plumbing without more liquid behind it.

If we turn to things with a pump the unusable quantity can go up, a lot.

The volume of liquid between the pump and the final destination would be considered unusable for the same reason - once the pump is dry we can't move it along anymore.

One restaurant manager I used to know installed a metered drink dispensing system.

All the booze is in the (locked) storage room, the bartenders push a button and exactly one ounce comes out of the tap.

The only complaint he had was that the system cost $500 to prime, per item , and he had to keep thousands of dollars of "unusable" alcohol on the books.

The term "unusable" is a very special definition.

It comes from a specific test described in FAA FAR Part 23.

It is not the same as the common sense meaning of the word "unusable".

For single engine light planes like Cessna 152, FAA FAR Part 23 requires the available fuel flow to be 125% of max engine consumption.

150% for pure gravity feed systems.

At certification test the fuel flow is measured while the level is dropping in the tanks.

As soon as the flow rate goes below 125 or 150 % all remaining fuel is declared unusable.

This shall be done with the plane supported in climb nose up atitude.

So, the formal term "unusable" means this last amount of fuel might be unavailble in a nose up attitude at full engine power.

In level cruise you can normally empty the fuel tanks to the last drop.

I pitch in blind here, but I believe in some instances fuel is circulated for heat exchange.

Question: I learned from  this question  that a Cessna 152 holds 5.6 litres of fuel that it can't use.   Why would it be designed to hold fuel that it cannot burn, especially since water contamination of fuel is a concern?

Why do aircraft have an unusable amount of fuel?

It seems planes may hold more fuel than they can use because some fuel is circulated for heat exchange.

Fuel is sometimes circulated for heat exchange.


Airplanes are much more efficient, much faster and scale better.

Helicopters are limited to around 150 knots because when flying forward the tip of the advancing blade must not exceed the speed of sound while the retreating blade must still move aft fast enough to produce lift.

Helicopters are also difficult to make large, because for efficiency the rotor disk needs to be large, but the diameter is again limited by the tip speed having to remain subsonic.

And the material requirements to make the blades strong enough without making them too large to keep drag low.

Jan Hudec's answer has already detailed why helicopters are not widely used for mass transportation or have been scaled up to ferry passengers more often.

The few exceptions exist where landing space is limited and the helicopter's maneuverability is more advantageous.

Offshore Oil & Gas Rigs

(Image Source: www.wn.com )

Where transport by ship is not fast enough or not possible due to heavy swell, the use of helicopters allows quick access to the offshore platforms.

New York

Helicopter Taxi

(Image Source: www.americanbestgetaways.com )

The New York Helicopter Services allow quick access to the airports around New York for business travelers who would otherwise take more time to arrive in Manhattan.

Spending years being ferried off and on shore by helicopters, I'd say the biggest problem is noise.

Even with a pair of decent ear defenders on it's not exactly quiet.

OK, so a commercial 'air bus' is never going to match a Mercedes or even a plush executive helicopter for levels of NVH, but there's nothing particularly attractive about the experience other than getting somewhere much quicker than you might otherwise.

The noise also means the 'go anywhere' ability of helicopters is severely curtailed if noise means they can't actually go many places.

Add to that the high cost

and it's pretty much a non-starter except for edge cases as in SentryRaven's answer where an increase of speed of an order of magnitude or more, or the circumvention of otherwise impossible access outweigh these concerns.

There are a few commercial passenger flights, but not so many because of the costs.

In Sao Paulo, Brazil, there are about 500 registered helicopters , with about 700 flights per day, which include transporting CEOs and politicians from one part of the city to another.

Several factors contribute to this: Frequent traffic issues leading to unpredictable delays in major roads; Presence of an elite having enough money to afford such flights; Availability of a sufficient number of helipads.

Some might also cite safety concerns, but this is unlikely to play a major role.

There was regular helicopter service between Tallinn, Estonia and Helsinki, Finland during the mid-2000's.

It was mainly used by business travellers between the two cities.

I think the flight time was something like 20 minutes and the heliport was on both sides conveniently in the middle of the city.

The regular plane service has a flight time of 30 minutes with additional time spent for airport procedures and taxi rides to and from the airport, so there definetely was a business case there.

However there was an unfortunate crash and the company never quite recovered from that.

They use their copters for oil rig flights now, if I am not mistaken.

See Wikipedia Copterline Flight 103 .

When I took flying lessons, I looked into a helicopter certification.

The rental cost was 2-3 times more than a fixed wing aircraft at the time.

I don't know what it costs now, but I assume it's still really expensive.

There are passenger helicopters, usually used by corporations or very wealthy individuals.

Some companies maintain their own fleet or charter when needed (which is probably cheaper).

One company I worked for early in my career maintained an intra-site fleet of helicopters (if your manager would approve it and the weather held, an hour drive became a 20 minute helicopter ride).

I never got to use it because this was one of the first things to go when the company went into decline and needed to cut costs.

Question: I've observed helicopters being used often   in the military  for medical flights  for other special use purposes, such as sightseeing and news reporting   Why aren't there any commercial passenger transport helicopter flights? Or are there any examples of this? Are airplanes simply that much more efficient?

Why aren't there more passenger helicopters?

Helicopters are not practical for passenger use. They cannot be made big enough to hold large numbers of people, they are very noisy and their range is limited. Planes are faster and more efficient.

There aren't more passenger helicopters because airplanes are more efficient and faster. Helicopters have a top speed of approximately 150 knots. Airplanes are also easier to scale up for passenger use. Moreover, helicopters are much noisier. The noise also means there are some places they can't go. In addition, there is nothing overly appealing about helicopters as a mode of transport other than getting somewhere more quickly.

Although there are some commercial passenger flights, the number is fairly low due to the costs involved. Passenger flights are often for business travellers, corporations or wealthy individuals. Helicopters are used for these purposes in Sao Paulo and New York, for example. In the mid-2000s, there was also a regular helicopter service between the capital cities of Estonia and Finland.

Helicopters are much noisier. The noise also means there are some places they can't go.

There is nothing overly appealing about helicopters as a mode of transport other than getting somewhere more quickly.

Some companies have their own fleet of helicopters or they charter them when they need them.