Questions tagged [landing-gear]

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

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4
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1answer
302 views

Do landing gear doors need repairs after a gear gravity deploy landing?

I know that landing gears can be deployed even without hydraulic power by letting them go down by gravity, as seen on this video: I was wondering: do the landing ...
4
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1answer
498 views

How does retracting the gear affect weight and balance?

In many of the POHs, in the W&B section it is indicated that there is a moment change due to gear retraction. For example : Moment change due to gear retraction +780 in-lbs. Two questions : If I ...
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2answers
874 views

Is there a formula for calculating the pivot point of an aircraft while turning on the ground?

I'm working on a program that requires a taxiing passenger aircraft (of any model) to perform a semi-accurate turn given a steering angle of the front landing gear. For this I need to calculate the ...
4
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1answer
162 views

Is the Dassault “ministop” related to the Dunlop Maxaret ABS?

Dassault fighters e.g. Ourargan and Mystere had Anti-lock devices called "Ministop" on main landing gear brakes. Anybody has a picture / drawing / detailed description ? Is the Ministop related to the ...
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2answers
2k views

Why complex landing gears are used instead of simple, reliable and light weight muscle wire or shape memory alloys?

Muscle wires actuators are really simple, have a high power density and are reliable. Landing gears on other hand are used only twice per flight while taking off and landing (if everything goes well ...
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1answer
949 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?
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5answers
1k views

Wheel or skid? Which advantages does each one have when used as the landing gear system compared to the other one?

I would like to discuss this topic in depth, as I have not found a clear answer yet. Which are the advantages of using skids instead of wheels (or viceversa) for the following considerations?: -As ...
3
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2answers
278 views

Which is the technically correct term: Nose Gear or Nose Landing Gear?

Talking about landing gear system, came across my mind the correct and technical name. Is it NOSE GEAR or NOSE LANDING GEAR?
3
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2answers
234 views

Why does only one hydraulic intake line from the reservoir have a filter on the Arrow II?

This is a portion of an Arrow II landing gear hydraulic system diagram. I noticed that there are two intake check valves, one located on each side of the pump, that would allow flow from the ...
3
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1answer
489 views

Why would a Blue Angels pilot leave their gear down?

In a recent Blue Angels airshow, one of the pilots had their landing gear down during the first 5 minutes of the show. What possible reasons would justify leaving the aircraft in this state? No ...
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1answer
580 views

How can the landing gear of an A320 be lowered in the event of a simultaneous hydraulic and electrical failure?

What is the process for lowering the landing gear of an A320 when the hydraulic and electrical systems are not operational? What happens to the aircraft when you lower the landing gear with ...
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3answers
379 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 ...
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1answer
680 views

What is the maximum nose wheel deflection angle?

What is the maximum nose-wheel angle of deflection on modern commercial aircraft such as the Boeing 787? Can it deflect to 90 degrees or even more?
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1answer
1k views

How does the landing gear damp vibrations?

How does a landing gear on an aircraft reduce the vibrations transferred to the airplane structure, while landing?
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1answer
265 views

Do airplanes have sensors to detect landing gear fires?

Given that retracting a landing gear that happens to be on fire is a suicidally bad idea, for reasons that should be immediately obvious, do airplanes have temperature sensors on their landing gear in ...
3
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1answer
442 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 ...
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3answers
834 views

Have Eddy current brakes ever been used/tested on an aircraft?

Eddy current brakes (wiki) --- a.k.a. magnetic brakes --- get quite some attention from train engineers. They are used on Shinkansens, roller coasters, and even (as far as I know) metro trains on Lane ...
3
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1answer
579 views

How is the due date for landing gear replacement determined?

I want to know how calculate the due date of Boeing MD-83 Landing gear replacement (it is every 10 year or 20000 FC). Is it calculated from the installed date or shop visit date?
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4answers
890 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 ...
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3answers
427 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 ...
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2answers
2k views

Is it possible to change/repair an aircraft tire while in flight?

Consider the following scenario: A crew experiences a flat/burst tyre above V1. Is it possible, in some type of aircraft, to change it while in flight? This might include, but not limited to: ...
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2answers
686 views

Do wheels continue spinning when gear retracted? [duplicate]

Do landing gear wheels continue spinning inside the landing gear compartment once the gear has been retracted or is there a mechanism that will stop them?
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1answer
562 views

How much force can the landing gear of a Piper Arrow withstand?

I'm currently working on my CFI-A in a Piper Arrow and i was wondering if anyone knows how much force the landing gear can withstand? The reason I ask is because I have never been asked this question ...
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2answers
1k views

Which compressed air and fluid are generally used by oleos?

Which compressed air and fluid are generally being used by oleo-struts?
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2answers
379 views

How much damage could a landing gear malfunction do?

How much damage could a total landing gear malfunction do to an airliner? Could the runway wear a hole through the plane?
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2answers
117 views

What is the difference between a 'live' NLG axle and a 'fixed' NLG axle?

What are the advantages / disadvantages of a live and fixed nose landing gear axle and how do they work? Maybe certain aircraft need a particular type fitted? I can't see the need of a moving axle (...
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2answers
542 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 ...
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2answers
2k views

How would we calculate the load factor on an aerial vehicle while landing due to sudden gust loads?

In order to design the landing gear (wheels and suspension) of our model Airship, [say "m" kg -expected mass], I wanted to know, is there any way to calculate the loads which might be experienced by ...
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1answer
96 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 ...
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1answer
838 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 ...
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0answers
261 views

What is the difference between a pressure switch, high-pressure control, and low-pressure control in a landing gear hydraulic system?

This is an Arrow II landing gear diagram. In the diagram, the high and low pressure controls look like check valves. The pressure switch is unclear. What are these three items, and what purpose ...
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0answers
358 views

How does the nose wheel tire stop rotating on retraction as the aircraft takes off? [duplicate]

As we know, the nose wheel tire and main gear tires are rotating when aircraft is taking off and the wheels are retracting. Thus there should be a mechanism to stop this rotation in order to prevent ...
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0answers
91 views

Why is there only circumferential treading on the nose wheel? [duplicate]

The pilot uses the nose wheel for steering on the ground, still all the tires on the aircraft use the same treading. Why are there no treads perpendicular to the rotation direction? I know that most ...
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0answers
74 views

What are the extra wheels for on the Harrier series? [duplicate]

On the Harrier series, what are the landing gears on the end of its wings for?
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2answers
666 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 ...
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1answer
153 views

Exceeding VLO and by how much is too much?

Piper Seminole (PA-44-180) VLO (max gear retraction speed) is 109 KIAS. I've heard that manufacturer published limitations are significantly lower than actual structural and system limitations. What ...
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2answers
171 views

For large commercial aircraft, how are the tires changed?

Something at least the size of a 737, all the way up to the A380. How are aircraft tires changed for large commercial aircraft? Are they actually jacked up like with a car?
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2answers
829 views

What is the purpose of the shuttle valve in a Piper Arrow's landing gear system?

This is the PA-28R-201 landing gear hydraulic system diagram. I am wondering how this shuttle valve functions. Research I have done indicates that a shuttle valve blocks one attachment to the valve ...
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2answers
258 views

How does pulling back provide better steering during rollout for light GA planes?

I had requested clarification on an answer to the question, How do I keep a C172 straight on the centerline during landing/rollout? I did not comprehend how pulling back after touch down provides ...
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1answer
402 views

How do aviation engineers ensure that the landing gear opens every time, without fail? [closed]

This is mostly with respect to large commercial airliners. I mean so many things can go wrong, then how have the engineers designed it to make it fail-safe? Or is it a very simple trick. Also, are ...
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1answer
97 views

What are the three sources that are relayed to the brakes and steering control unit of an A320?

There is the sentence: Electrical signals from the three sources are relayed to the brakes and steering control unit (BSCU) and are computed into the nose steering angle. The question: What are ...
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1answer
754 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 ...
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1answer
615 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 ...
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1answer
123 views

Who decides when landing gear requires an overhaul?

"If the landing gear on your aircraft is required to be overhauled periodically..." So is there a case where its been decided that landing gear does not require to be overhauled?
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1answer
277 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 ...
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0answers
176 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 ...
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2answers
3k views

How do plane landing-gear tyres roll before take off? [duplicate]

How do plane tyres roll? Are they equipped with special engines like cars or are they rolling using the plane flying engines? Or can both methods be found with different constructors?
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1answer
124 views

How does landing gear affect thrust on a light twin-engine airplane?

I'm working on my commercial multiengine rating. And I got this question from my examiner, and I answered: landing gear produces penalty drag, so it decreases thrust. But the examiner says this isn'...
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2answers
169 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 ...
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2answers
1k views

If a tail dragger is converted to a tricycle gear airplane, what will be the effect on weight distribution?

If a tail dragger airplane is converted to one with conventional tricycle landing gears, how will this affect the balance of the airplane? It is possible to offset the effect by shifting weights ...