Questions tagged [braking]

Questions about usage of mechanical brakes on the wheels for slowing down.

Filter by
Sorted by
Tagged with
5
votes
2answers
414 views

What is the effect of sudden extreme temperature change on brake disks of large aircraft?

What is the temperature of brake disks at maximum altitude of a jumbo like a 747 and airbus A380 for say a 10 hour flight. Does the temperature drop below zero and what is the effect on the metal ...
2
votes
0answers
93 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 ...
5
votes
3answers
1k views

Do parking brakes lock the wheels and airframe together?

(YouTube) Wildcat undercarriage. For planes with non-truck undercarriages, can they be rotated around the lateral axis of the main landing gear with the brakes applied without causing translation? ...
20
votes
3answers
4k views

Would a stationary WWII fighter fall on its nose with full throttle and brakes on?

Would a stationary WWII fighter fall on its nose with full throttle and brakes on? It's a general question, but I am interested in the Republic P-47.
-5
votes
1answer
4k views

How do multiple-disc brakes work?

Multiple disc brakes uses stators & rotors to brake? How do they work? (Source)
1
vote
1answer
298 views

What brakes are used between line-up and takeoff?

I was wondering if an airliner was instructed to line-up on the runway ("line-up and wait"), will the park brake be used or will manual braking be used (pedals) during the wait until the take-off ...
3
votes
3answers
904 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 ...
5
votes
1answer
4k views

How often are heavy aircraft brake pads changed?

How often are Boeing 747-800 and Airbus A380 aircraft brake pads changed?
10
votes
4answers
2k views

What is the preferred way to slow down an airliner on a long runway?

EDIT: Another way to phrase the question is, given an extra long runway, does it make sense to substitute mechanical braking (which is the primary way to slow down in a typical situation) partially or ...
19
votes
3answers
11k views

What is the temperature of the brakes after a typical landing?

On an airliner, what is the temperature of the brakes after a typical landing, and how long does it take to cool down? Is it hot enough that mechanics should wait before servicing an aircraft that ...
6
votes
1answer
415 views

How does EMAS reduce damage in case of an aircraft overrun?

I saw a report about Mike Pence's plane overrun today on Twitter link: Mike Pence plane overrun photo on Twitter. As can be seen there is huge cracks and breaking of the runway but the plane was ...
0
votes
1answer
262 views

Can an aircraft (civilian or military) land with its brakes already engaged? [duplicate]

Can an aircraft land with its brakes already engaged at the max landing speed of that aircraft?
12
votes
4answers
3k views

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 ...
16
votes
3answers
3k views

Why is the drogue parachute jettisoned on the runway?

Why is the drogue parachute of a military plane jettisoned on the runway? Why not drag it to the parking area for safe removal, inspection, and repacking?
10
votes
2answers
2k views

How does landing performance differ on water vs. ice vs. paved/grass runways?

It's a follow up from How do aircraft brake when using skis? Can someone give me data about difference between landing distance for each environment ? Paved Grass Water Snow/Ice Any aircraft is ...
20
votes
2answers
2k views

How do aircraft brake when using skis?

Planes use skis to land on ice/snow runaway. How can the plane brake in such conditions? Friction must be limited to allow takeoff and aerodynamic braking are not the main contributors to the ...
15
votes
2answers
3k views

Why aren't the canards used as airbrakes on the Tupolev Tu-144?

The Tupolev TU-144 uses retractable canards to stabilize the aircraft while starting and landing. On this picture you can see them very well: Source: AirlineFan.com Copyright: VOLPATI It doesn't ...
18
votes
2answers
2k views

Why do modern jetliners provide Thrust Reversers at all in their design decisions?

Let's start with the following knowns (please correct me if I am wrong about any): The braking force provided by the wheel brakes is much larger than that by the thrust reversers One is not allowed ...
12
votes
1answer
731 views

What are the relative braking contributions from wheel brakes, spoilers and thrust reversers?

What is the relative contribution to braking forces in a typical large commercial aircraft from the three different devices contributing to braking after touchdown: Wheel brakes Speed brakes / ...
40
votes
4answers
8k views

Do commercial aeroplanes use ABS to brake?

I have read that the wheel brakes on an aeroplane are by for the most efficient means of stopping it. I was wondering whether in low grip situations, such as in rain or snow, an ABS (Anti-lock Braking ...
3
votes
2answers
3k views

Where is the regular wheel brake input on modern airliners?

I learned that on modern airliners, the Rudder input is given by the pedals located under the pilot's feet, and that got me thinking: how do the pilots give the command to brake the plane in order to ...
2
votes
3answers
629 views

what are the ways to avoid skidding off the runway apart from thrust reversers? [duplicate]

what are the different ways to avoid skidding off the runway apart from thrust reversers? Do crew have any option if thrust reversers are not available and the ground is too slippery which is making ...
7
votes
1answer
11k views

In an emergency, how much runway does an A320 need to stop safely?

From time to time I land at Wellington Airport in an A-320. The runway has sea at either end and is 2,081m (6,827ft) long. There's never been a problem but I find landing there a bit nerve wracking ...
7
votes
1answer
3k views

What is Brake To Vacate (BTV)?

Emirates has this feature on many of its A380s. From what I've read, the feature decreases the amount of runway an aircraft uses after landing. It also helps the aircraft achieve a certain exit way. ...
21
votes
1answer
3k views

Can the wheel brakes hold an airliner in place if its engines are at full thrust?

Are wheel brakes on most commercial jet airliners capable of holding the jet stationary on a dry surface, if all the engines are given full thrust? Could doing this be potentially unsafe or damaging ...
0
votes
1answer
1k views

Do landing planes brake with wheel-brakes or air-brakes or both? [duplicate]

I suppose they do both, but what percentage of the kinetic energy is absorbed by the wheel brakes and what percentage by air-friction (in typical cases)?
13
votes
9answers
64k views

Does a plane have brakes to stop or slow down while flying?

Does a plane have brakes to stop or slow down while flying? For example, if the pilots see a large flock of birds at some distance in front of the airplane, and they want to reduce speed suddenly. ...
1
vote
1answer
918 views

How does a typical passenger jet come to a stop when it lands [duplicate]

Do the pilots of the plane simply reverse thrust of the engines after touchdown or are there brakes on the landing wheels that slow the plane just like a car? Or a combination of both? What about ...
4
votes
1answer
797 views

Does the A380 have more than one auto-brake disengage switch?

I know that the A380 has low/med/high RTO auto-brakes. What I'm not sure about is if there's a switch near the thrust levers that can disengage the auto-brakes, other than the switches located on the ...
22
votes
4answers
4k views

When the brakes are checked, what do the firemen actually do?

Watching this video (at 06:58 mark), this plane had just made a mayday landing, due to a bird-strike. Because of the right engine being shutdown, it was forced to land immediately, with a full load of ...
26
votes
6answers
8k views

Why tap the brakes on take-off in fixed gear aircraft?

The Socata TB10 checklist indicates that you should touch the brakes after lift-off. I assume this is to stop the wheels from turning, but why? In a retractable gear aircraft this would make sense to ...
9
votes
4answers
2k views

What is the effect of changing the autobrake setting after touchdown?

If an autobrake setting is chosen prior to touchdown, but after touchdown and nosewheel compression (i.e. after the autobrake has engaged) a different setting is required, is it safe to change the ...
14
votes
4answers
13k views

What is the advantage of combining the rudder and brake pedals in aircraft?

I've read about several aircraft having their rudder and brake pedals very close together. To me this seems confusing and prone to error. It looks easy to mistake the rudder / brake pedals and ...
5
votes
2answers
853 views

What are the pros & cons of Autobrake?

What are the advantages/disadvantages of an autobrake system? In particular I am interested in the Fokker 100 system. Have any studies been done for the F100 autobrakes and the affects that this ...
8
votes
1answer
4k views

How does autobrake work?

An autobrake is a type of automatic wheel-based hydraulic brake system for advanced airplanes. The autobrake is normally enabled during takeoff and landing procedures, when the aircraft's longitudinal ...
13
votes
3answers
15k views

What is differential braking?

How is differential braking different from regular braking? How do you accomplish differential braking and why would you need to use it?
30
votes
6answers
15k views

For large jets, what is the primary means of slowing down after landing?

I understand that a large(r) commercial jet slows down after landing using the following methods: Wheel brakes Reverse thrust Spoilers/flaps/airbrakes What is the effectiveness of each compared to ...
5
votes
1answer
551 views

How much does pilot technique affect brake life?

Anecdotally I have heard of various things that I can do to make steel brakes last longer before they have to be replaced, and they make sense but how much does it really help? Things that I have ...

1
2