HPSOV failure and its effects

[metalmike 34]

Hey there, sorry to resurrect such an old thread, but I've encountered this same "failure" on a flight to HNL. I didn't get any EICAS warnings, just noticed BLEED HPSOV L on the AIR page. 

 

I actually looked this up in the FAA's 777 Master MEL, and it reads:

"(M)(O) One may be inoperative provided:

a)       Inoperative HPSOV is locked closed,

b)       Opposite engine bleed system operates normally,

c)       Both outflow valves operate normally,

d)       Airplane remains at or below FL 350, and

e)       Associated engine bleed air is cycled OFF, then ON at 55% N1 or greater before takeoff.

 

 

I figure it would be kind of cool to simulate a MEL'd flight back to an airport with a maintenance base (in this case SFO). I feel like a bit of a doofus asking this, but is it possible to lock an HPSOV closed in the sim? I could easily meet all the other requirements. Or should I just clear the failures and get on with it?

[metalmike 34]

Sorry I meant it was on the STATS page, not AIR. Anyway, I'm on the return flight now, and now that indication is no longer displayed on the STATS page. However, it still comes up under my active failures list.

[Budbud 227]

Hi,

 

I take the opportunity to ask a silly question because I often have that failure and couldn't find the correct procedure in the QRH:

_ First how to be sure whether the HPSOV is stuck closed or open?

_ Second, what are the correct in-flight actions to take when the failure occurs during the different stages of the flight?

(Switch off the engine bleed, switch off the related pacs, turn APU on...)?

 

I guess that if the failure occurs during any stage of the flight where the engine are not idle, the HPSOV would be stuck closed? But what if it is stuck opened?

 

Thanks.

[scandinavian13 5,192]

 

Sorry I meant it was on the STATS page, not AIR. Anyway, I'm on the return flight now, and now that indication is no longer displayed on the STATS page. However, it still comes up under my active failures list.

 

You broke my plane? Maaaaaaannnn...I was going to take it back to IAD today from LHR, but I guess not 

(I'd give you a vatstats link, but our office firewall has blocked it for some reason...huge threats there apparently  :rolleyes: )

 

 

 

As far as the failure goes, remember that failures might not always be visible. The cool part of this simulation is that some failures are like icebergs. They might give a little bit of an indication from time to time on the surface (the EICAS or STAT page), but the real "danger" lies deeper. This, over time, may trigger other symptoms/failures.

 

Moreover, there are even more nuisance failures that, depending on your flight status (airborne or on the ground), the 777 will filter out for you because there's nothing that you can do about them in certain cases. There's more on this in the intro manual. I definitely recommend having a look. It's cool stuff.

[downscc 1,327]

Moreover, there are even more nuisance failures that, depending on your flight status (airborne or on the ground), the 777 will filter out for you because there's nothing that you can do about them in certain cases. There's more on this in the intro manual. I definitely recommend having a look. It's cool stuff.

 

Otis Elevator was the first company to network their products (elevators) to obtain maintenance data in the world before internet, it was normal for the local elevator repairman to show up before the building manager knew there was a problem.  Now we have engines communicating directly with company maintenance and the amount of information is staggering. Not surprising given the investment that the engines require.  It was this 'background' communications channel that was used to try to find MH370 I think.

[Budbud 227]

Wow, has someone ever got that in a single flight (10.5h)? Almost everything pertaining to the pneumatics failed during the flight!

I'm wondering if the x20 does any good to the failure generation, based on the MTBF? It remains very strange that I get a pneumatic failure on one flight over two servicing or not the pneumatics. But this flight was the worst ever. I was closed to expedite the descent in emergency to 10000ft when I saw both PACS going off due to the low bleed pressure (engines idle)... but fortunately (and probably normally), I didn't get any pressurization issue.

 

Nice end of flight with the air demands C1 and C2 pumps off, no APU, bleed air low pressure, no PACS... (all related to the HPSOV valves stuck closed)!