Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

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

2
votes
1answer
60 views

What are the potential threats of having the landing gear dirt from mud in a rectractable landing gear airplane?

Recently I have been flying an aircraft with the landing gear very dirt with mud due to the parking area of the airfield on grass and the meteo conditions in recent days. I wonder what are the threats ...
3
votes
4answers
118 views

How can drag induced by the landing gear be reduced?

What are some of the methods used to reduce the drag caused by the landing gear for aircraft with non-retractable landing gear?
3
votes
0answers
58 views

Does the PA-44's squat switch disable the stall warning?

I've read the AFM and looked online about the gear system for the PA-44 Seminole and there is apparently a squat switch on the right main gear that disables the stall warning whilst on the ground. ...
40
votes
4answers
9k views

Do military bases still employ wheel watchers?

When I was in the air wing in the '70s, I had the unpleasant opportunity of pulling wheel watch. The unfortunate individual sat in a small shack (maybe 3 x 6 ft.) with a pair of high-powered ...
1
vote
1answer
124 views

What is the purpose for two nitrogen charged chambers in an oleo strut?

What is the purpose of a twin nitrogen charged chambers oleo, such as the one illustrated below? Why is it used and what are the advantages compared to a conventional mono-nitrogen chamber? Training ...
6
votes
1answer
250 views

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?
2
votes
3answers
282 views

Are all tires on an aircraft replaced at the same time?

On cars, it is often to replace all four tires at the same time. Is this true also for aircraft? I imagine the nose gear and main gear probably can be replaced at different intervals. However, are ...
15
votes
1answer
2k views

Are there any aircraft with powered landing gear?

My student asked me a question this morning. It was: A car drives by turning its wheels against the Earth. An airplane taxis by rolling on its wheels while the engines push against the air. Are ...
0
votes
1answer
85 views

How to determine the maximum servo torque required for a nose gear?

It's pretty much it. I know how to calculate the friction force on the nose gear for a three-point landing condition using the method set forth in ...
9
votes
1answer
2k views

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 ...
6
votes
1answer
954 views

How is a light plane's nose wheel straightened during retract?

Assuming a light aircraft has direct cable linkage to the rudders, during taking off in a very strong crosswind with the pilot correcting with hard rudder, what keeps the nose wheel from remaining off ...
7
votes
2answers
293 views

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 ...
3
votes
3answers
286 views

Could a plane land on specialized vehicles if its landing gear failed?

This (fake) video has stirred up a lot of questions online about whether such a scenario would be possible in reality - and the answer to those questions appears to be a resounding "No, that's very ...
-3
votes
1answer
193 views

Is it possible to remove an A320's main gear using one main jack and one nose jack?

I have only one set of jacks (nose-main LH and RH) and I need to swap the main landing gear from one aircraft to another. I don't have a dummy landing gear. Is this possible?
3
votes
1answer
304 views

Do Airbus aircraft have an “off” position for their landing gear?

I know some Boeing aircraft feature an up, down, and "off" position for their landing gear lever. I know that some Boeing wide-body jets do not have a 3rd lever position, but still have an "automatic" ...
0
votes
2answers
188 views

How much more economical are planes with retractable gears vs. those with fixed gears?

Many small planes have fixed gears, some have retractable gears. All things being equal, the plane with retractable gears would have to be more expensive than fixed gears, as the mechanisms involved ...
0
votes
0answers
65 views

Where can I find the main landing gear and MLG bay dimensions of an A350-900?

The most information I have found was from this Airport and Maintenance Planning report by Airbus but it does not include any of the landing gear or bay/well dimensions. The main landing gear is ...
2
votes
2answers
278 views

What are ways to reduce drag and noise generated by the landing gear?

Apart from using fairings, what ways are there, or have been studied, but not necessarily implemented in reducing drag and noise produced by the landing gear, mainly for commercial aircraft with ...
74
votes
1answer
10k views

How is tire rubber removed from the runway?

Every time an aircraft touches down, the tires are spun up rapidly. As a result, some rubber is left at the touchdown zone. (image source) As time goes on, more rubber is accumulated at the ...
19
votes
5answers
5k views

Why do landing gears smoke upon impact?

I have been observing several aircraft landings and have noticed that when the aircraft's landing gear touches down, it precipitates the rising of a cloud of smoke. Why is this? (Source: airliners....
0
votes
0answers
21 views

Is there a way to easily calculate the forces an actuator requires to move parts of the landing gear?

I need approximate values to feed into Solidworks. For example, the retraction actuator that pulls the entire assembly into the wheel compartment.
3
votes
1answer
286 views

Are nose wheel tyres designed differently from the main wheel tyres?

For the heavy large Jumbos like the Airbus A380 and the Boeing 747-800, considering nosewheel tyres are not subjected to the excessive heating caused by braking from the disks and brake pads, and ...
4
votes
1answer
288 views

What is the air temperature inside of a tire right after landing?

What is the maximum design air temperature inside of a tyre of an Airbus A380's and a Boeing 747-800's main gear fitted with brakes, before landing after a 10 hour flight and right after landing? Are ...
11
votes
2answers
2k views

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?
5
votes
1answer
310 views

Do the landing gear modules rotate?

I'm particularly thinking about larger aircraft with more than two sets of main landing gear. It's pretty obvious you would not want them to rotate while landing and take-off, but while taxiing ...
9
votes
2answers
653 views

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?
3
votes
0answers
395 views

What is the maximum weight on the main gear of a large aircraft at rotation and touchdown?

For a large aircraft like a B747 or A380, how much does the weight on the main gear increase when the nose gear is in the air? I mean, in these two cases: What is the maximum extra weight on the main ...
8
votes
1answer
427 views

Does the 747-8 / A380 nose-wheel encounter more weight during braking?

Given that the nose wheels of both the Boeing 747-8 and Airbus A380, as is true for almost all aircraft, are not equipped with brakes, do they encounter more weight during braking? If so, how much ...
5
votes
1answer
186 views

On the new A320s when we do a brake check there is no need to call pressure 0 why?

Why do we have a give a pressure 0 call out when checking brakes while taxi on the old A320s but not in the newer A320s.?
1
vote
0answers
164 views

Why do we have to do an alternate brake check during preliminary cockpit preparation?

As part of the preliminary cockpit preparation in my company’s older A320s we have to perform an alternate brake system check but not in the newer ones as per FCOM Normal procedures as below. I found ...
10
votes
1answer
2k views

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 ...
0
votes
0answers
99 views

How long does the gear extension/retraction takes on the ATR-42?

Which is typical time of landing gear extension in normal conditions ? I would like to know it especially for the ATR-42 but any other typical value is welcome ! Furthermore can you provide any link ...
4
votes
2answers
464 views

Is wheel well overheat detection (not brake temperature sensor) necessary for commercial jet aircraft?

Some aircraft do have this detection system (many Boeing aircraft), some do not. Why? What's the main purpose of the wheel well temperature detection system, even though there are brake temperature ...
3
votes
1answer
523 views

Who manufactures the landing gear on the Airbus A350 series aircraft?

Where are they made? I assume that they are made out of titanium. Right?
6
votes
1answer
857 views

Runway landing with a front skid instead of wheel - how does steering happen? (Dreamchaser)

The Spaceflight Now article Sierra Nevada’s Dream Chaser performs critical glide test flight shows the Dreamchaser performing a runway landing using a front skid and two wheels. The skid extends ...
0
votes
0answers
51 views

What aircraft are most commonly equipped with skis?

I have flown a Cessna Caravan with skis, and flown in Twin Otters with skis. I have also seen a variety of modern production aircraft with skis, including C182, C206, and a variety of older aircraft. ...
5
votes
1answer
740 views

How does the wheel speed sensor in a Boeing 777-300ER work?

I do have a maintenance manual that I found on Internet, but it doesn't have anything about the wheel speed transducer. Any pics along with the information would be helpful.
22
votes
6answers
19k views

Could airline tires be deflated in mid-flight to reduce weight?

As a means of weight reduction to reduce fuel consumption, could the tires on an aircraft’s landing gear be deflated once airborne then re-inflated just prior to landing? Is that feasible and safe?
3
votes
2answers
462 views

Are tracked landing gear systems still in use and development?

In the 1940's and 1950's, there were several tracked landing gear systems developed for the purpose of allowing landing on soft ground and/or using particularly heavy aircraft such as the B-36. Are ...
5
votes
2answers
451 views

Do airliners use light alloy wheels, like cars do?

Do large and small airliners - up to jumbos like the Boeing 747 and Airbus A380 - use light alloy wheels in their landing gear to reduce weight? If not, why not? Are there reasons unrelated to ...
7
votes
5answers
2k views

Has there ever been a seaplane with inflatable airbags rather than traditional pontoons?

Traditional pontoons are big and cause a lot of drag. It would be nice to retract them like normal landing gear but they are just too big. Has there ever been a seaplane with inflatable airbags ...
1
vote
0answers
145 views

Why are aircraft tires not pre-spun prior to landing? [duplicate]

Currently, as far as I know, most modern (big) airliners do not pre-spint the tires before landing. The question is why not, as there are certain benefits. This question was asked here before Why are ...
2
votes
4answers
523 views

Is it feasible to recuperate energy from landing aircraft by using a runway sled with regenerative braking?

Would it be feasible to land large (Boeing 747 and Airbus A380) and all other aircraft on a sled on the runway, the kinetic energy of the aircraft is then transferred to the sled, then the sled uses ...
0
votes
2answers
153 views

Is there a way for an aircraft to tell a ground station when the gear is down? [closed]

Is there any way that someone on the ground can be informed if the landing gear is down? It could be an ACARS message sent to the ground center, or a specific light (sequence) from the aircraft that ...
6
votes
2answers
733 views

Should an emergency field landing be performed with landing gear down or up?

Suppose you are flying an aircraft with retractable gear and have to make an emergency landing on that big "flat" stretch of grass up ahead and have only one shot at it, what's better, do it with ...
2
votes
1answer
572 views

Can light aircrafts with no retractable landing gear make an emergency water landing? [duplicate]

In the suburbs of Lisbon today two people were killed because a pilot of a light aircraft (I imagine without retractable landing gear) landed on one beach full of people (it's Summer and the beaches ...
5
votes
1answer
2k views

What defines a landing gear bogie?

(Wikipedia) A Boeing 737 main landing gear arrangement. What defines a landing gear bogie (truck)? In its airframe maintenance handbook, the FAA defines it as: When more than two wheels are ...
10
votes
3answers
889 views

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 ...
26
votes
6answers
6k views

Why use an airplane with non-retractable landing gear for aerobatics?

I'm watching footage from Red Bull Air Race 2017 in Kazan (one example is ) and clearly at least some of the airplanes used have non-retractable landing gear. I was ...
22
votes
3answers
4k views

Is there a landing gear system that extends automatically to prevent belly landing?

To my knowledge, most aircraft with retractable gear are equipped with a landing gear warning system that makes repetitive beeping sounds in case the pilots try to land without the gear down. I ...