some 737 questions
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some 737 questions
hi all
APU to be shutdown,pack off,apu bleed sw off or just pack off and wait a minute before shutting down ?
where's that requirement stated about not using APu bleed for 1 min before shutting it down?
APU running : where the heck is that information not to open the rear service door whenever the APU is running ?
i saw one time that the restriction not to start APU during refueling was deleting from Boeing, i can t find out that anymore.
there a couple of persons unfortunatly working with me that consider themselves rocket scientists they look for any information and hide it from you. those are instructors that before asking you questions on a checkride they read the books and ITS answers. they don't even know what the answer is and when you don t know that answer.....you're the worst pilot in the world.
I am telling you this guys because i wanted to share my story with you,some people looks no matter what to destroy your dream to be a pilot,some people succeed before you because the used "the alternative method to succeed" (gifts,money,transportation,girls....)
you don't succeed because you are using the normal way,UNFORTUNATLY that's what's happening to me !
APU to be shutdown,pack off,apu bleed sw off or just pack off and wait a minute before shutting down ?
where's that requirement stated about not using APu bleed for 1 min before shutting it down?
APU running : where the heck is that information not to open the rear service door whenever the APU is running ?
i saw one time that the restriction not to start APU during refueling was deleting from Boeing, i can t find out that anymore.
there a couple of persons unfortunatly working with me that consider themselves rocket scientists they look for any information and hide it from you. those are instructors that before asking you questions on a checkride they read the books and ITS answers. they don't even know what the answer is and when you don t know that answer.....you're the worst pilot in the world.
I am telling you this guys because i wanted to share my story with you,some people looks no matter what to destroy your dream to be a pilot,some people succeed before you because the used "the alternative method to succeed" (gifts,money,transportation,girls....)
you don't succeed because you are using the normal way,UNFORTUNATLY that's what's happening to me !
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when you are going to shut down the aircraft, be sure you let a minute pass after turning the apu off before disconnecting the main battery so the inlets can close back there.
you let the apu run, if required, while re-fueling.
after start during taxi once clear of obstacles you shut down the apu. it has been taking a breather ( no loads at all ) is stabilized and appreciates special care.
you let the apu run, if required, while re-fueling.
after start during taxi once clear of obstacles you shut down the apu. it has been taking a breather ( no loads at all ) is stabilized and appreciates special care.
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Hey FMC,
At my airline we got memo's that the 1 minute is not applicable anymore.
APU bleed may stay open on the ground (normal situation), in the air APU bleed off (normal situation).
APU start is now allowed while fuelling.
Indeed wait at least 20 seconds with battery to off after APU shut down.
At my airline we got memo's that the 1 minute is not applicable anymore.
APU bleed may stay open on the ground (normal situation), in the air APU bleed off (normal situation).
APU start is now allowed while fuelling.
Indeed wait at least 20 seconds with battery to off after APU shut down.
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The reason why it would be nice not to run the A.P.U. with the rear service door open is that the air intake is just behind it. Any loose items being loaded into the rear galley tend to get sucked into it. This causes the A.P.U. to either "run hot" or shut down!.
I have not heard any hard and fast rules regarding the shutting down of the A.P.U. but it always good practice to let ANY engine run at idle with the loads off for a few minutes before shutting down.
Rgds Dr I.
I have not heard any hard and fast rules regarding the shutting down of the A.P.U. but it always good practice to let ANY engine run at idle with the loads off for a few minutes before shutting down.
Rgds Dr I.
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On the NG's (-800 at least) switching of the APU switch will trip the APU Generator of the buses and close the APU bleed valve. The APU itself will keep running for another 60 seconds....this then covers the one minute cooling/stabilising of the APU, which is a requirement according to my Systems Manual. After shutdown the APU Inlet Door will close in approximately 30 secs. So we leave the Battery Switch on for 90 seconds after switching the APU off. Still, although the APU bleed valve is closed as well automatically, you should still switch off the APU Bleed Air switch, especially before flight. Otherwise, should you need the APU inflight, the bleed valve will re-open, resulting in a Dual Bleed. Also we need to wait one minute after starting the APU before we can take bleed air, another reason to have the bleed switch OFF.
Myself I never heard of the rear service door restriction, but Ilitout's remarks make good sense, although in my company we frequently replenish catering through that door with the APU running.
Finally, a memo in our company recently stated the following: Boeing no longer has any technical objections against starting or shutting down the APU while refuelling. My company added to this that this is just Boeing, and that country, airport and/or fuelling company regulations might (read: will) still not allow this.
The other week my captain started the APU while refuelling resulting in a furious fueller.
Hope this helps.
Regards Z.
Myself I never heard of the rear service door restriction, but Ilitout's remarks make good sense, although in my company we frequently replenish catering through that door with the APU running.
Finally, a memo in our company recently stated the following: Boeing no longer has any technical objections against starting or shutting down the APU while refuelling. My company added to this that this is just Boeing, and that country, airport and/or fuelling company regulations might (read: will) still not allow this.
The other week my captain started the APU while refuelling resulting in a furious fueller.
Hope this helps.
Regards Z.
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Any decent veteran fueller knows he should wear ear plugs or go deaf. There is sufficient noise at most busy airports to warrant protection so if he complains he must have other things in mind, all i can say is that itīs his problem, not yours.
Maybe the fueller got jumpy when the captain ran the fire test and the horn in the wheelwell went off momentarily.
Most airports have a APU use limit but until they hook up a GPU we keep it running. Many places they overlook the APU lmit and they all allow refuelling with APU on too.
Maybe the fueller got jumpy when the captain ran the fire test and the horn in the wheelwell went off momentarily.
Most airports have a APU use limit but until they hook up a GPU we keep it running. Many places they overlook the APU lmit and they all allow refuelling with APU on too.
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thank you guys for all your answers
but for the 1st question i didn t find a complete answer.
when i say no bleed using for 1 min before shutting apu down does that mean
(pack switches+ apu bleed switch OFF)
or
(just pack switches off ,apu bleed sw on) ?
some of rocket scientist pilots says that leaving the apu bleed valve on "because it is "electrically controlled " and pressure operated" will permit APU start when there's no power at all just battery. i don t believe at this though.
concerning rear sce door opening during APU usage,i know it s been implemented because some plastics stuff (bags,cups ...) if thrown maybe suckes into the inlet .....but where is that WRITTEN ? is it a boeing recommandation? where can we find it ?
but for the 1st question i didn t find a complete answer.
when i say no bleed using for 1 min before shutting apu down does that mean
(pack switches+ apu bleed switch OFF)
or
(just pack switches off ,apu bleed sw on) ?
some of rocket scientist pilots says that leaving the apu bleed valve on "because it is "electrically controlled " and pressure operated" will permit APU start when there's no power at all just battery. i don t believe at this though.
concerning rear sce door opening during APU usage,i know it s been implemented because some plastics stuff (bags,cups ...) if thrown maybe suckes into the inlet .....but where is that WRITTEN ? is it a boeing recommandation? where can we find it ?
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Hey FMC,
The SHUTDOWN checklist says APU BLEED AIR SWITCH 'ON'. The SECURE checklist thereafter says PACKS 'OFF'. Nothing is mentioned about the APU BLEED AIR SWITCH. So you could leave it 'ON'. AOM (FCOM) vol. 1, normal procedures.
The APU BLEED AIR VALVE is indeed pressure operated and DC controlled. When the APU is 'OFF' the APU BLEED AIR VALVE is closed (no pressure). BATTERY 'ON' is all you need to start the APU. The position of the APU BLEED AIR SWITCH has nothing to do with this, it could be 'OFF' aswell (theoratically). AOM (FCOM) vol. 2, chapter 2.
Regarding the 1 minute. After APU start it must be operating for 1 minute before switching PACK(S) 'ON', on the CLASSIC and the NG. On the NG operate the APU for 1 minute with no bleed air load (PACKS 'OFF') prior to shutting it down. AOM (FCOM) vol. 2, chapter 7. Although I got a memo, for the CLASSIC, saying something else.
All the above is not the law, but when your instructor, cpt or examiner asks, you have at least something on paper.
About the rear service door CLOSED with APU running I couldn't find anything written. I assume it is just good practice.
PS. After APU shutdown indeed wait for approx. 2 minutes (after the APU GEN OFF BUS light extinguishes) before switching the BATTERY 'OFF', on the NG. On the CLASSIC, 20 seconds (APU inlet door closed). AOM (FCOM) vol. 1, normal procedures.
Take care.
The SHUTDOWN checklist says APU BLEED AIR SWITCH 'ON'. The SECURE checklist thereafter says PACKS 'OFF'. Nothing is mentioned about the APU BLEED AIR SWITCH. So you could leave it 'ON'. AOM (FCOM) vol. 1, normal procedures.
The APU BLEED AIR VALVE is indeed pressure operated and DC controlled. When the APU is 'OFF' the APU BLEED AIR VALVE is closed (no pressure). BATTERY 'ON' is all you need to start the APU. The position of the APU BLEED AIR SWITCH has nothing to do with this, it could be 'OFF' aswell (theoratically). AOM (FCOM) vol. 2, chapter 2.
Regarding the 1 minute. After APU start it must be operating for 1 minute before switching PACK(S) 'ON', on the CLASSIC and the NG. On the NG operate the APU for 1 minute with no bleed air load (PACKS 'OFF') prior to shutting it down. AOM (FCOM) vol. 2, chapter 7. Although I got a memo, for the CLASSIC, saying something else.
All the above is not the law, but when your instructor, cpt or examiner asks, you have at least something on paper.
About the rear service door CLOSED with APU running I couldn't find anything written. I assume it is just good practice.
PS. After APU shutdown indeed wait for approx. 2 minutes (after the APU GEN OFF BUS light extinguishes) before switching the BATTERY 'OFF', on the NG. On the CLASSIC, 20 seconds (APU inlet door closed). AOM (FCOM) vol. 1, normal procedures.
Take care.
Last edited by Alaskan Timber; 11th Dec 2004 at 19:53.
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If you are being hassled by a smart-arse check pilot (there are a few around otherwise they wouldn't have the job) just ask him sweetly if he can tell you what is the alternate power source of the cabin call button. Personally I haven't a clue, but for those check pilots with no sense of the ridiculous (the majority) it usually stops them in their tracks for a while. Better still, the really zealous idiots will go home that night and spend hours trying to find the answer.
PS. It is important to look real serious when you ask the question.
PS. It is important to look real serious when you ask the question.
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Just An Observation
Truly there are at least 5 pricks for every 50 normal pilots. And yes it seems they are the ones that wiggle their way into instruction positions. Do keep the mouth shut until on-line and do RTMīs ( read the manuals ) and specially know where to find info when queried.
I wouldnīt try and outsmart anybody.
I wouldnīt try and outsmart anybody.
