Questions tagged [landing-gear]

The wheels of an airplane. Sometimes replaced by floats or skis.

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4answers
5k views

How do landing gear retracting into the wing affect performance when deployed?

On many aircraft with low wing, landing gear (either wheel, leg, or both) retracts into the wing. Thus, when deployed, a significant part of the lower surface of the wing is not as clean as when the ...
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1answer
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Helicopters with landing skids, no wheels; How are they taken in and out of a hangar?

I'm sure many helicopters also need/use Hangars frequently. How do you take them to a hangar and take them out of it without wheels? Specially when they have to be taken indoors for some maintenance ...
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What happens to the spinning wheels of the landing gear after takeoff, before retraction?

What happens to the spinning landing gear right after V2 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 ...
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2answers
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What causes an airplane to rhythmically bounce during taxiing?

Some time ago, I was on a commercial flight and while the airplane was taxiing around, there was this rhythmic bouncing. Here is a video I made of the takeoff. You can notice the bouncing at the taxi ...
15
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1answer
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Do landing strips suffer from potholes or rutting?

In companion to the other question asking about wheel tire tracks. Planes come down and stop with a significant amount of force which I would expect to cause either rutting or potholes. Are runways ...
15
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1answer
865 views

Why is the Antonov 225 (almost) always chocked at the third wheel?

Recently I was looking over pictures where the An-225 is parked (because that's a normal thing for a normal person to spend their time doing). I noticed that the chocks are almost always placed around ...
14
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Are there any aircraft with a 4-wheel nose landing gear and a 16-wheel main landing gear?

Are there any aircraft with a 4-wheel nose landing gear and a 16-wheel main landing gear? I need this to answer my review of an aircraft design project.
14
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3answers
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Why doesn't the landing gear get raised on the first flight of a new airplane?

This image shows the A350 first takeoff high in the air and the landing gear is still down. Why didn't they retract it?
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Does it make sense to do an emergency landing without nose gear in order to reduce stopping distance?

Would a pilot decide to land without the nose gear down to increase friction if for example all the engines have suffered a flame-out and there is only a very short runway available ?
14
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3answers
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What are the advantages and disadvantages of having landing gear doors?

To make comparison easy, let us take the example of B737 and A320, both similar aircrafts with retractable landing gear. As seen on the photo below, the B737 doesn't have gear doors for the wheels, ...
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2answers
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Why did some aircraft use hand-crank instead of gravity for alternate gear extension?

I wondered whether the final scene in The Memphis Belle where they hurry to extend the gear by hand crank (because their electric system failed) is realistic, but according to this answer the B-17 ...
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4answers
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Is it possible to control an aircraft on the runway if the nose gear collapses?

I have read and seen some articles in which, for various reasons, the aircraft's nose gear collapsed after landing during the roll out. This resulted in the aircraft going off the runway. Is it ...
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If the landing gear is stuck in an airliner, can the crew go down and manually open it?

There are several instances where we see the landing gear getting stuck before landing. In these kind of situations, can the crew, or one of the pilots, go down to the landing gear area and solve the ...
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How is the 737 main landing gear protected from weather?

I really like the 737, it is perhaps my favorite airliner. One curiosity of this aircraft (afaik, it is the only commercial airliner) is that the main landing gear has no cover: Here is another ...
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3answers
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Does Nitrogen inside commercial airliner wheels prevent blowouts on touchdown?

I just watched the first episode of Inside Mighty Machine where civil engineer-turned-host, Chad Zdenek, discussed innovations of the 747. One innovation he discussed was the increased number of ...
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4answers
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What effect would there be if the brakes were locked at touchdown?

I'm imagining if you had a panicky passenger sitting in the right seat who had both feet firmly on the brakes while landing. Unless you had a crosswind and needed rudder as you touched down it's ...
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How to execute a gear up landing on aircraft with low propeller?

On some GA aircraft such as the Piper Malibu, the propeller would touch the ground if the gear was up. How would you land the plane when gear actuators fail? I would pull out the mixture knob and ...
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Why wasn't the 737 MAX's landing gear lengthened enough to mount the engines under the wings, rather than in front of them?

The reason Boeing originally added the MCAS to the 737 MAX was to compensate for a slight pitch-up moment generated by the engine nacelles at very high angles of attack. This pitch-up moment occurred ...
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3answers
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Is there a best number of wheels per bogie?

I understand the need of having more wheels when the aircraft is designed to be heavier. The number of wheels per bogie and the number of bogies differ from an aircraft to another. For example, there ...
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What is the cause of the noise heard when the landing gear is deployed?

Why is it that on most airliners, when the landing gear gets deployed, you always hear a loud noise like a bang. Is this due to the equipment locking in place or is there some other reason? As an ...
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4answers
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Could a pick up truck save a plane with failed landing gear?

I recently saw this fictionalized video. While it's not real, I do wonder if this could be possible, even if not the best way to handle the situation.
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1answer
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Why do some A320s have double-bogie landing gear?

I believe this is actually a rare sighting, but why do some A320s such as the VT-ESD have double-bogie landing gear? Does Airbus have a specific reason for making such A320s? Update: Found an image ...
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7answers
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Has there ever been a tail-dragger with retractable tail-gear?

This comes from a slightly related question about drag from landing gear. A tail-dragger is the old-school layout of aircraft, particularly WW2-era fighters. It's also known as Conventional Landing ...
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Has there ever been an uncommanded lowering of landing gear?

Has there ever been an uncommanded lowering of the landing gear on a large commercial jet? I could not find any instance of it in a preliminary google search. Could a simple short-circuit cause such a ...
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1answer
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Why does the A-4 Skyhawk sit nose-up when on ground?

The rear of the plane is nearer to the ground, while the front part of the plane is away from the ground (see image below). Other planes are more flat. I think it was for high AoA but these planes ...
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2answers
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What is this item on the nosewheel of the Sukhoi PAK-FA?

I noticed a small item on the rear side of the nose wheel in multiple images of the Sukhoi PAK-FA, shown below. The item in question appears to be a grille wrapping around the back of the tires and I ...
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1answer
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What does shimmy in nose landing gear mean?

While I was reading a small article on "Reasons for RTO", I came across a situation where the pilots aborted takeoff because of "landing gear shimmy". What does that mean?
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1answer
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How heavy are the Boeing 747 landing gear?

Does anyone know how heavy are the combined landing gear on a Boeing 747? It would be interesting if someone has also weight statistics per gear (nose gear and the four other main gear).
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Do aircraft tyres have inner tubes?

Do aircraft tyres have inner tubes? Modern small single-engine turboprops to the largest Jumbos. If not, did they ever have inner tubes? And if so, why were they discontinued?
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Is the landing gear controlled by the pilot or is it automatic?

I have been watching a few aircraft landing videos in crosswind situations and I noticed that if the airliner missed the runway the landing gear would go back into the aircraft. So I'm wondering if ...
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Why is the main landing gear of the Cessna Caravan placed so far forward?

Why is it that the rear landing gear of the Caravan is placed so far forward? I understand that the center of gravity must lie somewhere in the middle between the nose gear and the rear gear but ...
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Why does landing gear retract with an offset?

I've noticed this often in flight simulators, and have, to be honest, never paid attention to it in real life, though I'm quite sure it happens there too: When landing gear retracts (and I believe ...
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What is the piece that covers the top part of tires?

I would like to know the name and the usefulness of this piece that covers the top of the tire of some planes, such as some Cessnas.
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How much extra drag does landing gear incur?

How much extra drag does landing gear incur? I'm interested in large commercial airplanes. For a concrete example, let's say a 747 flying at 1,000 m above sea level at 800 km/h. Edit: Looks like 800 ...
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How can the Antonov AN 225 only have 2 nose wheels?

I was watching the video of the AN 225 unloading at Perth airport this weekend, and it suddenly occurred to me that there are about a zillion rear wheels on the aircraft, yet only 2 nose wheels? ...
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2answers
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Why is the gear handle shaped the way it is?

In the aircraft cockpits I've seen, the gear handles all seem to have the same general shape (they look like a little wheel). Is there a reason for this beyond simply making it absolutely obvious that ...
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1answer
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How is Spitfire landing gear powered?

I have seen a WW2 movie where the pilot of the Supermarine Spitfire has difficulties to extend the landing gear as the engine is no longer running. This would be reasonable if the gear normally needs ...
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1answer
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Why do some commercial aircraft have no landing gear cover? [duplicate]

The B737 has no cover on its landing gear, as may be seen in this picture. Doesn't this increase the air drag? Almost all other airliners have doors that close off the rubber of the wheels, for ...
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1answer
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Can the Landing gear be lowered when system A hydraulic pressure is lost in Boeing 737?

In the FCOM OF BOEING 737 HYDRAULIC SECTION I went through the part Landing gear transfer unit that it is used to raise the landing gear at a normal rate when system A EDP volume is lost. My query is ...
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Could landing gear weighing scales be used to detect lack of lift?

There have been several crashes due to ice on wings destroying lift. One of the issues with this is that you can't detect that you don't have sufficient lift until you're already in the air, way too ...
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Will the landing gear work mechanically in case of total power loss?

In case of a total power failure in all the aircraft systems like engine failure and APU failure, would it be possible to use mechanical means (manually) to open the landing gear bay door and deploy ...
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Why did the backup landing gear deployment fail on LOT 16?

LOT 16 was a 767 which experienced a hydraulic leak, resulting in the failure of the landing gears and the proceeding belly landing shown below: Why did the backup ...
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Is there no warning if landing gear is not retracted during flight?

I know that most aircraft have a warning system which makes beeping sounds if an aircraft tries to land without the gear down. After reading this news article about an Air India flight 676 flying ...
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Is it feasible to add an aftermarket hydrofoil to a light aircraft?

Could long, aftermarket hydrofoils be added to the water-skids of a plane (like this Cessna with pontoons or smaller) Cessna 208 Caravan not designed to have a hydro foil, to increase its ability to ...
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Why is the Constellation's nose gear so long?

The Lockheed Constellation has an enormously long nose gear, which causes the aircraft to slant appreciably backwards when sitting on the ground: L-049 (Image by Greg and Cindy at Flickr, modified ...
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1answer
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What did the “gear warning horn” on the North American P-51 sound like?

I'm working on a sound project for a P51 simulation and I'm having real trouble trying to find a reference on how the P51 gear warning horn sounded like. What mechanisms were used in the '40s to make ...
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How realistic is the plane scene in Captain America: The First Avenger?

In Captain America: The First Avenger, there's a scene in which Captain America gets into the villain's plane by holding onto the landing gear as it's taking off and waiting for it to be retracted. ...
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How does the nose wheel lock on the Robin DR400 work?

I recently learned that there is a locking mechanism on the nose wheel of a Robin DR-400. This mechanism locks the nose wheel in place when there is no weight on the wheel. In particular, the wheel ...
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1answer
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What is the purpose of the small wheel at the end of the F-14’s launch bar?

At the end of the launch bar (catapult strop link) on the F-14 airplane, there is a small wheel. Does anyone know what this is used for?
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1answer
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How often is a tire replaced on a 777?

Given that it is long haul aircraft, and is most widely used by airlines in that capacity: How often do they replace the whole tire? How much does 1 tire cost the airline?