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-   -   Cooling brakes with water as a normal procedure (https://www.pprune.org/tech-log/525817-cooling-brakes-water-normal-procedure.html)

Don_Apron 21st October 2013 07:05

nitpicker330

"being retracted" I meant in transition. That process begins when the gear lever is moved to the up position.

I should qualify I was referring to cargo ops, which normally inured higher weights.

We did not have brake heat sensors, like they do now..

Yes we carried out a fire warning check which included the WW fire detection system, as required by the checklist.

Tyre incidents are still happening too frequently.

We never trusted the Ground/base engineers completely as their a:mad:s would not be strapped to the aircraft.

From which direction would you approach suspected hot tyres or brakes?? Serious question, as they can even kill you on the ground.

Hope that helps.

nitpicker330 21st October 2013 08:19

1/ as a cockpit crew I wouldn't ever approach hot brakes, especially ones that had melted fuse plugs and deflated tyres..........not my job:ouch:

2/ I'm told that if the brake assembly explodes it usually does to the side, therefore approaching from directly in front or behind is best if you have a suicidal tendency...:D

3/ you'll see me running away with my pax well away from the brakes, I'll sit back and watch the show from a safe distance....:ok:


p.s no wheel well system fire detection loop will detect a wheel or brake fire during retraction unless it's a damn hot and a big event. I thought that would be obvious!! :eek: when you wrote "after retraction" I thought you meant after the cycle completed and it was all buttoned up....:)

Natstrackalpha 21st October 2013 09:47

A320 Brake fans
 
A good invention - except the fans blow air over the sensors which give a lower, cooler indication on the flightdeck. so for hot brakes - temp could be a lot higher.

nitpicker330 21st October 2013 10:59

I still say lucky you!!

Better than none, believe me..:{

Don_Apron 21st October 2013 12:07

Nit

Are you one of those Qantas sky Gods? I think you might be. Should have known better to even query such a superior. You need to learn to accommodate other peoples point of view with a little more tolerance. I don't know all the answers and neither do you.

The moment that gear lever is in the up position after liftoff, on the aircraft I am referring, your fate would sealed if you have burning or flailing wheels. Wheel well fire detectors or no ww fire detectors. That was all I was trying to explain.

nitpicker330 21st October 2013 12:29

No not a Qantas sky god as you put it. I'll take it as a compliment though as I have a lot of friends in QF that are top notch operators and I could only hope to keep up to their professional standings.

You seem a bit touchy, what was it that I wrote that was wrong exactly?

How do we differ in our opinions anyway? I actually think if you re read my posts we agree generally.

I answered your "serious question" about how to approach hot brakes, was I wrong?

Now take a chill pill and settle down. :ok:

bcgallacher 21st October 2013 13:16

Nitpicker - be aware it is not the brakes that will explode it is the tires, but it is correct to approach from front or rear as the bits of tire usually go laterally.Frankly it is better to stay a long way away from a smoking landing gear as debris can travel quite a distance and a large chunk of tread can do a great deal of damage. The fusible plugs will usually let go before the tire reaches bursting pressure due to heat but you cannot tell if there is damage to the carcass that might allow it to burst at a lower temp.I worked as a line engineer for 40 years and always treated hot wheels and brakes with the utmost respect - they are capable of killing you.

Burnie5204 21st October 2013 13:20


From which direction would you approach suspected hot tyres or brakes?? Serious question, as they can even kill you on the ground.
Fire crews here say "DONT", let them do it instead.

However, they will approach it at 45 degrees to the direction of the bogey as if it causes the tyres to explode then most rubber will be flung out at 0, 90 and 180 degrees and hub assemblies normally get thrown out at around 90 degrees

Natstrackalpha 21st October 2013 14:56

bc gallacher
 

Nitpicker - be aware it is not the brakes that will explode it is the tires
I was going to say that . . .!

nitpicker330 21st October 2013 23:58

Yes true wheels exploding/brakes exploding. All the same area caused by hot brakes. As I said I won't be going anywhere near hot brakes/wheels, not my job. :ok:

Hadn't heard about the 0 90 and 180 rule. Good to know for Fire fighters...:eek:

Shawn Coyle 22nd October 2013 21:14

So if pouring water on hot brakes is a bad thing, does that mean you can't taxi through puddles of water?

BARKINGMAD 24th October 2013 13:29

BEST PLACE FOR THE SLF THEN?!?!?!
 
"However, they will approach it at 45 degrees to the direction of the bogey as if it causes the tyres to explode then most rubber will be flung out at 0, 90 and 180 degrees and hub assemblies normally get thrown out at around 90 degrees"

"Frankly it is better to stay a long way away from a smoking landing gear as debris can travel quite a distance and a large chunk of tread can do a great deal of damage. The fusible plugs will usually let go before the tire reaches bursting pressure due to heat but you cannot tell if there is damage to the carcass that might allow it to burst at a lower temp.I worked as a line engineer for 40 years and always treated hot wheels and brakes with the utmost respect - they are capable of killing you."

"Yes true wheels exploding/brakes exploding. All the same area caused by hot brakes. As I said I won't be going anywhere near hot brakes/wheels, not my job."

SO WHY ARE THE FLIGHTCREWS THESE DAYS SO RELAXED ABOUT THROWING THEIR PAX DOWN THE SLIDES FOR A BIT OF SMOKE AND FIRE WHERE IT IS EXPECTED?

AH WELL YOUR HONOUR, SOMEONE SAID "FIRE!" AND I KNEW LEGALLY I'M COVERED IF I EVACUATE THE PASSENGERS!

PERHAPS A BIT OF THOUGHT AS TO WHAT HAPPENS TO THEM OUT THERE MAY JUST STAY THE HAND BEFORE THEY REALLY GET UNNECESSARILY INJURED?!?!

I now await the incoming fire.........................................:ugh:

Desert185 24th October 2013 15:03


I now await the incoming fire.........................................:ugh:
Not from me. To evac or not depends on the situation.

Gas Bags 25th October 2013 03:24

There is no procedure to use water to cool overheated brakes...the opposite is the case. You should always wait for natural cooling or use cooling fans. Using water on an overheated brake could cause an explosion.

Any one using water has a death wish....Fools and beginners???

bcgallacher 25th October 2013 14:12

Gas Bags -
Boeing had a permitted procedure for spraying water in what they described as a fine mist above the brakes and allowing it to settle on them.What you are supposed to use to produce this 'fine mist' I have no idea. Worst case I witnessed was in Bangkok where local mechanics were pouring water from water cooler containers onto the brakes of our 747 producing large volumes of steam and creaking noises. That was how I found out why we had so many cracked wheels - it did not happen again.

sb_sfo 25th October 2013 14:22

fine mist
 
A fire department fog nozzle will do the trick- seen it done about 20 years ago. Weren't many other choices available.

BARKINGMAD 25th October 2013 14:34

Gas Bags, your posting is my understanding also after only 4 decades of professional flying.

What worries me as an old codger is an apparent forgetting of lessons learnt a long time ago in aviation.

I had the same scenario at a regional UK airport last decade, when our NG arrived on the stand with a new brake unit smoking gently on it's first outing into this airport where the runway is not very long.

Fire crew attending were determined to hose it if it looked like it would combust, the off-going captain, a former flight engineer was saying 'no way Hosé', and a real argument developed between the 2 parties.

If this sort of behaviour is symptomatic of the modern aviation "professionals" and their support staff, then it's only a matter of time before the old lessons will have to be re-learned the hard way, and at what cost!

Any engineers/firefighting professionals out there who would like to comment? :suspect:

bcgallacher 26th October 2013 00:39

SB SFO -
Thanks for the info - did not know that such a thing existed - I once had an African fire crew on standby with what was termed a roseate head when I knew a certain captain was operating as he seemed totally incapable of landing the thing without overheating the brakes - fortunately never had to use it.

Killaroo 26th October 2013 05:17


Nitpicker330: I think you misunderstand what I've been badly trying to say!!
HaHa - it's your TONE old boy.
But being Australian you'd never understand.
Free CRM lesson there.

Killaroo 26th October 2013 05:31


Natstrackalpha: A good invention - except the fans blow air over the sensors which give a lower, cooler indication on the flightdeck. so for hot brakes - temp could be a lot higher.
Actually, Airbus give two different values for max temp depending on whether or not you have fans. I'm sure NitWit is just wetting himself to tell us the number (I know it nitty, so get it right).

I learned this trade on aircraft with no brake fans, and no brake temp gauges.
How did we ever survive before wunderkinds like nitty came along to teach us how to fly.
BTW, Did those QF Sky Gods taxi through the puddles? Tsk Tsk. Flying should stop in heavy rain!


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