APU Question

[Qavion2 39]

Not sure what you mean by the -8. The RAT is for Hydraulic System 3 only.

 

 

I guess I skipped a step or two in the comment   I meant they had a rethink regarding the addition of a RAT to replace some of the functionality of the engines. I assume the -8 doesn't have the capability of using this hydraulic pressure to generate electricity? The 767 couldn't do this either (It had a RAT, but it couldn't divert the hydraulic pressure to the HMGs to produce electricity from hydraulic pressure).

 

Cheers

John H Watson.

[thibodba57 462]

I guess I skipped a step or two in the comment   I meant they had a rethink regarding the addition of a RAT to replace some of the functionality of the engines. I assume the -8 doesn't have the capability of using this hydraulic pressure to generate electricity? The 767 couldn't do this either (It had a RAT, but it couldn't divert the hydraulic pressure to the HMGs to produce electricity from hydraulic pressure).

 

Cheers

John H Watson.

No Boeing still has not given up their stance that the statistical likelihood that you lose all 4 engines is completely unlikely. Even though it has happened a couple times and has almost happened to one of our -8s (multiple engine rollback due to icing).

[phil747fan 14]

what bring Boeing to re-design from the classic where the APU can be started in the air then the -400 no more?

[Qavion2 39]

It was probably safer not to have it operate in the air (statistically).

 

They have been known to catch fire. There is only one fire bottle, but I suppose another could be added, but it's difficult to know what's happening to it, though, when it's sitting in the tailcone.

 

Cheers

John H Watson

[phil747fan 14]

John,

 

thanks for the head. never asked the maintenance when they did an overhaul of the classic fleet, no ops bulletins associated with it, so i imagine with the years more and more issues or the wore out ... i ve seen -341 and -269b with still the sticker operation in flight authorized ...