…if the APU GEN L+R have to be On during flight, or should I switch them Off ?
You turn APU gens and the APU off after engine start as all your power will be supplied through engine generators.
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@Skandinavian941
You don’t touch the generator switches, neither in the sim, nor IRL.
They remain in the ON position.
After engine start you only turn the APU off.
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While in flight or on the ground with engines running, the four engine generators are the primary sources of electrical power and the APU generators are secondary. Your APU is off while all four gens are on with engines running, this is what your photo depicts. If your AC bus was powered by the APU you would then want them on. You can even cut #2 while pulling into the gate as in most companies require, given APU Gen is available via a running APU you could then cut R1 & R3 after switching on APU GEN R repeating for #1 shutdown when parking brake is set and nose wheel is chalked. Can’t wait for QW Sim.
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I’m sorry, i’m used to Airbus systems, and it’s more clear there (imo). But here, with the B787, i switch off the APU, once the engines are up and running of course. But couldn’t help myself wondering if then the APU GENs had to remain On, or if I’d better switch them Off. MagicDrake1207 said what actually was on my mind. PZL104 knows apparently the 787 irl. I understand your answer, but not really the correlation with my question. No offense.
Thank you ALL for your help, from now on, i’ll switch them off after my engines will be up and running.
Thanks a mil again for your kind help.
Happy flying
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APU Generators should be kept on at all times, no? Even in Airbus too. You just need to switch off the APU master switch, but the generators should always be on regardless.
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No, I don’t know the 787. It’s a guesstimate because that’s the way you do it from the 737 up to the 777.
Since the 787 is a completely different animal concerning electrical power, it might be possible that Boeing had to change this procedure.
Reading @KillerJackson82s reply it seems that he knows the 787 very well.
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Perhaps Boeing knows it better than any of us?
If I’m not mistaken at one point there was a failure in a certain part that mandated the procedure being to leave the APU gen switches be, and this was rectified some years back.
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I don’t see any hint that the APU generators need to be turned on or off separately.
Yeah and that’s alright if we don’t. It’s fine either way. Hell, leave em on if you wish. And happy flying
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The point is that I’m not aware of any Airbus or Boeing where you touch the APU generator switches during normal ops.
Where did you get all the info from you posted in your initial reply?
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Thanx for the links, but I still don’t see anything about the APU generator switching.
Am I missing something?
Perhaps a company ops manual? Aside from that the systems work the way they work. So who’s to say what procedures to follow. I would only say that if your APU is running they need to be on and if the APU is off and you’re on GND or 4 GENS then it can be off. Unless stated otherwise by your carrier ops.
The question was if it is procedure to manually switch the APU generators on or off.
Do have the appropriate normal procedures and/or checklists?
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That is perhaps what I am best trying to allude to here is that it isn’t even listed in any set of standard procedures.
If it’s not listed in the SOPS it’s obvious that they stay on at all times…
like in all the other Boeings and Airbuses.
I don’t know, the only thing I know that is if it was so ‘obvious’ to me it would be sated as such to be left on at all times. And it isn’t. In fact the procedure is listed in preflight to turn them on form being off. I’m not sure that this would mandate in any way to that they should be left on at all times.