Where do fire crews check the temperature of the brakes?
 

Hi all,

In the case of an emergency involving heavy use of the brakes, the fire crew can check the brakes/gear. Some fire crew will have IR thermometers to check the heat emanating from the brake units. Where exactly would they check or would they be just scanning all over looking for hot spots?

Why on earth would fire fighters want to do that?

They'd better stay clear of the wheels until the fusible plugs have released the tire pressure. Then they'll be alert for smoke and fire. After a high energy stop the brake disks are white-hot, no need to measure the temperature.

Thanks for the reply but it's not quite what I was getting at. It's an esoteric question about brakes and temperatures. Hypothetically, where and how are the brake discs measured accurately? Less from a daily operational perspective and more from an engineering/systems knowledge point of view.

Many aircraft have brake temperature indicators in the cockpit - if you can communicate with the crew via a plug in headset they may be able to give you brake temps. If you want to point an IR device at a brake unit do it from in front or rear of the wheel assembly - not from the side. as when a tire lets go that is where most of the fragments go. There will be no hotspot on an individual brake - the rotors and stators are just a large mass of hot steel or carbon.

Brake temperatures
 

There is a brake temperature monitor on the flight deck. On older airliners a thermometer can be stuck up the rear toilet drain out let.

The individual brake temps are read by thermocouples attached to the brake units which project into the rotor/stator assembly.

In terms of brake temperature testing the fire crews do a quick assessment using a Thermal Imaging Camera to look for any abnormally hot areas which would indicate a fire.

An even heat signature indicates normal operation, a heat signature with heat pattern eminating upwards indicates fire. Fire crews can't normally determine whether a brake unit has overheated - only whether they have overheated to the point of fire

"Where do fire crews check brake temps?" From as far away as possible if they are smart! There is good reason to use "tire cages" when inflateing aircraft tires which run up tp 240PSI, and thats the "cold" temp , even after a normall lading the brake discs will be cherry red. {PS, Brits can change this to "tyres" if they so wish}

Can we change 'inflateing' to 'inflating' and 'tp' to 'to' and 'lading' to 'landing' and 'normall' to 'normal' too?

Damn, Canadian is worse than American! Oh, I got it - sent from a 'Smart' phone!;)

No, not frum a shsmart phone, I was ejumicated in the UK {no kidin!}, yeah, fingers too damn big for these "micro pads!"

Fire fighting crews attending an aircraft can talk to the flight crew via radio on 121.6MHz (at least in the UK). As for checking temperatures, our fire fighters use a thermal imaging camera from a safe distance.

On the 747 it takes up to 15 mins for the flight deck indications of brake temps to stabilise to anything meaningful.

Which is why we use brake energy charts.

Fire Crews: Thermal Imaging Cameras.

Flight Crews/Mechanics: Charts and IR Thermometers.

777 doesn't even show actual temperature of the brakes, only units. The higher the unit the hotter the brake. :ok:

1 to 7 I think from memory? Up to about 5 or so on normal landings, anything above that was getting warm!!

GERBY:

:}

Looks like your efforts went un-noticed :ok:

Thankyou Mr Good Cat
 

Forty years flying and 57 types. I got through it because of a sence of humour and a healthy respect for hot things (including tyres).
Early in my flying career was told of an incident in Africa where a B.O.A.C. Britania or Argonaut's tyre exploded with dire results to people crowded round the wheels.

Don't forget - Some commercial types have no brake temps and some have them deferred for a few days if inop. So the question is valid!

Unlike anything/one who has had a thermometer can be stuck up the rear toilet drain :uhoh:

Esoterically, I believe that a modicum of common sense is used!

Many thanks for the responses. Burnie5204 & reportyourlevel hit the nail on the head as far as what I was looking for.