Brakes

[TAAMGuy]

How often are brakes changed on an airliner?

[gorter]

facetious answer: when they need to be

to give accurate answer need type of a/c, type of brake (steel/carbon), type of ops, the cost focus of the airline (whats more expensive, engine wear or brakes) etc etc etc.

sorry but there is no correct answer (and i'm being gentle).

[TAAMGuy]

I'm just looking for a generic answer. LEt's say a B737NG.

[glum]

Seriously, when they're worn out. Depends entirely on what the aircraft is doing - long haul, short haul, long runways, wet weather, fully loaded, how long the taxi is...

[dhardesthard]

There is no generic answer. An airline that operates half its 737s(and there are several types) on 5 hour sectors will wear out the brakes 5 times as fast as the same airline that operates its other 737s on 1 hour sectors. That assumes that the same pilots operate the A/C into similar length runways at similar landing weights and a host of other variables. The closest you can get to an answer is if you ask a specific airline and even so brake wear rates will vary tremendously. Any particular reason you need this information?

[Junkflyer]

Brakes are changes when the wear indicators are shown to be at their minimums. (typically pins flush with the housing with the brakes being set.) There is no time/cycle limit that I am aware of. The caveat is if the a/c is at a maintenance base going out on a long-haul trip or during a higher level check, the brake may be changed before it hits mins to save the hassle later.
High weights, short runways and crew usage will affect the life. No simple answer to this question.

[grounded27]

Brakes are changes when the wear indicators are shown to be at their minimums. (typically pins flush with the housing with the brakes being set.) There is no time/cycle limit that I am aware of.
Company can request that the pins are cut (and usuallly are) above minimums.

[TAAMGuy]

I understand everything posted but I just wanted a rough order of magnitude. Is it weeks, or months or years???????????

[Beeline]

Airbus. Single aisle family roughly 0.003" per landing.

Brake material is often not a uniform datum amount on installation, so quite hard to tell. Roughly the pin starts off about 2.5".

Obviously then it it depends on how hard you hammer your aircraft and the mentioned variables.

[RVF750]

Brake wear is a massive variable. opinion and types vary but usually a short haul airliner will see a brake unit change needed anywhere from a month to a year depending on use.

Carbon brakes wear at different rates to steel. Carbon brakes do not like being ridden on, i.e. trail braking continously or against power. The technique of rolling along at idle then applying once to bring speed down to walking pace before completely releasing in cycles is meant to help reduce wear or so we are told.

Sorry there is no definitive but brake wear is such a huge variable.

[Kuchan]

TAMMguy

How often do you change your car brake pads????????? 3 times a year, once a year or every 3 years.

I change mine when I hear the screeching metal noise the brake pad made when braking.
That was more than 4 years ago as I do more on motorway than city driving.