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Old 26th July 2009 | 14:00
  #13 (permalink)  
Denti
 
Joined: Mar 2001
Posts: 4,563
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From: I wouldn't know.
No need for bleed air from the APU?

- how would you start the engines?
- how would one dry crank an engine in case of tail-pipe fire?
- how would one keep cool in all of those greek airports which doesnt even have ground power :P

I think the apu will live for a long long time... =)
All true in conventional aircraft, but no longer true in Boeings future scheme of things starting with the 787. "More electrical" airplanes, as Boeing calls it, do not need bleed air for all that. The engines are started electrical with their starter generators (787 two 250kVA per engine), not with bleed air anymore, which eradicates the first two problems. And the packs are driven electricly as well which helps keeping your head cool.

Granted, in existing planes we will have turbine APUs for a long time come, even in the 787 we will have it for quite some time (driving two 225kVA starter/generators), but in other future projects or even as a replacement packs fuel cells are quite possible.
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