B737 APU automatic fire discharge ?

[BaByJet]

Let's say:

that the pilots have left the aircraft with the APU running and no ground crew is around and the APU catches fire.

The APU will automatically shut down BUT is there an automatic fire extinguisher discharge feature as well?

I believe that I have seen that described some place but I cannot find it in my current AOM.

bbj

[Shaka Zulu]

Ehm, i don't think that holds true do.
I've just read some things from the computer based training 737 NG and they don't state an automatic discharge function.
It does auto shutdown as you correctly mentioned, but to my knowledge it will NOT auto discharge the one fire bottle the APU has got.

[mutt]

that the pilots have left the aircraft with the APU running and no ground crew is around and the APU catches fire.

I would assume that "automatic" termination of the flight crew would follow........... :):)


Mutt.

[pancho]

In my experience on the 73 the crew would never leave the aircraft with the APU running with no one qualified to take over. If there was a delay in change over and they had to move on (go home or change aircraft) a full shut down was required.:O

[PifPaf]

Hey Mutt, you were perfect!
Just to remember, we could keep a maintenance person outside the aircraft, since there is an APU shutdown/fire extinguisher device in the main wheel well.

PP

[BaByJet]

ASFKAP, Thank you for a strait answer.

I guess some of the other replies focuses more on the setup than the question itself.

Your answer is in line with what most of my colleagues say.

bbj

[fruitloop]

quote..Just to remember, we could keep a maintenance person outside the aircraft, since there is an APU shutdown/fire extinguisher device in the main wheel well.
"yep and some are hooked up and tested".

[arba]

When they are not around (the ground crew) and I have to go (either to another airplane or home) I'll proceed with TERMINATION C'LIST ... day or night.

[QAVION]

"I've just read some things from the computer based training 737 NG and they don't state an automatic discharge function."

Generally, just be aware that with automatic discharge on some aircraft types, it may be airplane specific. In our 747-400 fleet there is one aircraft which does not have this function, the rest do. I would advise asking the advice of your engineering technical specialists if you have any doubts.

Also be aware that a particular auto-extinguishing system may be operative on the ground, but not in the air.

Regards.
Q.

[Shaka Zulu]

Right, kept that in the back of my mind, since the 73 is my first a/p type ;)
It seems daft not to install it on the 73 as well then, they all come from the same factory. Just a small electronic adjustment i'd say

[CI54]

Hi all,

Where I'm flying, the B737s have APUs from two different manufacturers. Initially we were using the GTCP85s, then changed to APS2000s, then 3 yers back we changed back to the GTCP85s. I do not recall the APS2000s having the auto discharge function. The GTCP85 is definitely fully manual except for the auto shutdown function for low oil pressure, fault, overspeed and fire. No auto discharge...

Rgds...

[Right Way Up]

There is an option on the NG for auto discharge!