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scott967

Help! Bleed air drops when I start engines/ they don't spool up

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On my LDS 767-300 and my IFDG/PSS A320series I have the following problem: whenever I "ignite" the engines, bleed air drops to zero and the engines don't start. I can see how N2 spools up, but N1 won't kick in. I haven't encountered this problem on other planes (for example PMDG 744, PSS Dash).I don't think I am doing anything wrong: the APU is running, and the EICAS shows that there is bleed air. It is only in the moment that I ignite that bleed air drops to zero. Also, I am not doing anything differently than over the past year(s).I really cannot explain why that happens. Anyone knows what I can do to resolve this problem? Any FS9 file that is corrupted?ThanksChrisPS: this is stupid, but let me ask nevertheless: I've only had this problem as of recently when simulating flights in North America and Europa, where weather was always below 10 degrees Celsius - could that be a cause?

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>On my LDS 767-300 and my IFDG/PSS A320series I have the>following problem: whenever I "ignite" the engines, bleed air>drops to zero and the engines don't start. I can see how N2>spools up, but N1 won't kick in. I haven't encountered this>problem on other planes (for example PMDG 744, PSS Dash).>>I don't think I am doing anything wrong: the APU is running,>and the EICAS shows that there is bleed air. It is only in the>moment that I ignite that bleed air drops to zero. Also, I am>not doing anything differently than over the past year(s).>>I really cannot explain why that happens. Anyone knows what I>can do to resolve this problem? Any FS9 file that is>corrupted?>>Thanks>>Chris>>PS: this is stupid, but let me ask nevertheless: I've only had>this problem as of recently when simulating flights in North>America and Europa, where weather was always below 10 degrees>Celsius - could that be a cause?Switch off the packs make sure youve got 40 psi and youll be fine.

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No, this behaviour is normal and you simply have to turn the air-conditioning packs to OFF before starting the engines.You see, you only have one source of pressurized air available. Either compressed air from the APU or from an external source (Air Starter Unit).When you have the aircondition running, most of this compressed air is used by the aircondition to cool/warn the cabin.If you attempt to start the engines without shutting off the aircondition first, then the amount of pressurized air that will reach the engine stage 2 (or stage 3 on RR engines) blades is not enough to rotate them fast enough in order to start the reaction.That's why you see a spool up on N2 but not on N1, the N2 blades do start to rotate with that minimal air but they don't provide enough air pressure at the engine exaust to start rotating the engine fan (N1).So, as already said, turn off the aircondition (Packs) prior to engine starting, wait for the pressure indicator to show you at least 35PSI, and then start the engines, one at a time, from right to left.Even better, read the manual of the aircraft for a more correct procedure.BTW, the Airbus 320 series does the a/c packs shut off automatically,so you shouldn't have a problem starting the engines there.Have you moved the engine master switch to "Start" ?George DorkofikisAthens, Hellashttp://online.vatsimindicators.net/811520/1704.png

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I think that could be "Engine Slow Start" or "Compressor Stall" but I don't think there are failures in FS9 that would sim that, so most likely the above posters are correct, insufficient bleed air manifold pressure for the starters. IRL I think there can be problems with engine internal bleed air, but this is not the same as customer bleed air that is supplying the whole A/C. scott s..

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