757 RB211-535 TRs after fire warning

[blue up]

As per the title, does anyone know with 95%+ certainty whether thrust reversers are inhibited after an engine fire warning or even just during the warning?
Tech manual not very specific.
I was asked this by an awkward bu66er during a refresher course.

Thanks.


PS I did ask the 'spanners' but they didn't know, either.

[mono]

No. A fire warning won't inhibit the T/R's.

However, if the QRH is followed then following pulling of the fire handle there will be no hydraulic supply to the engine and therefore no T/R operation.

[Avionker]

Hydraulics? If the reverser is hydraulically actuated then that is a big difference to the other RB211's I have had experience of.

My experience with RB211-535's is all on 747's however I do not believe that the reverser will be inhibited due to a fire warning.

Provided the aircraft is in ground mode, all relevant c/b's are set and pneumatics are available the reverser should operate if commanded.

[spannersatcx]

My experience with RB211-535's is all on 747's

Interesting, never seen a 535 on a 747 only 524's!

[Avionker]

I'll get me coat.....

Yep -524, that'll be the one I've played with, D's and G's I think. Let me amend that statement then.

"Provided the aircraft is in ground mode, all relevant c/b's are set and hydraulics are available the reverser should operate if commanded."

Would you agree with that Fargoo? Or are there any interlocks other than air/ground mode?

[Swedish Steve]

Well a few years ago there was an engine oil pressure switch involved as well. They were only operable with engine running. There was also an override switch for ground use under the fan cowl.
But it was all taken off about 10 years ago on our aircraft.
Maybe someones still got it?

[HAWK21M]

On the RB211-535....TR is NOT Inhibited during the fire warning.But pulling of the Fire handle will depressurize Hydraulics on that system EDP.

[CF104]

757 T/R

On the RB211-535....TR is NOT Inhibited during the fire warning.But pulling of the Fire handle will depressurize Hydraulics on that system EDP.

Although the EDP supply SOV is closed with the fire handle pulled, this in itself doesn't inhibit the T/R as the ACMP is still supplying system pressure. Pulling the fire handle actually removes control power to the T/R isolation valve which is what actually disables it.

Cheers,

John