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Old 26th September 2005 | 11:40
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coded_messages
 
Joined: Aug 2005
Posts: 92
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From: UK
1) I think this is due to the fact that if you took fuel from the CWT and then the mains you would pretty much soon go out of the C of G range which is around 8.5% - 33% for every ton of fuel in the stab it changes the C of G by 45 units. Also if Fuel gets caught in the Stab it can lead to many problems - Maybe Boeings logic is to get it out asap

2) Hard to give you this in a post! General overview is that the cabin is pressurised with conditioned air from 3 packs. 2 Outflow valves at the rear of the aircraft regulate the amount of air discharged. these are controlled by 2 cabin altitude controllers 'a' and 'b' and only one is active at a time.

The Cabin altitude controller maintains pressure - The max being 8.9psi and the structural limit being 9.4psi at 39,000ft with 8.9 psi it generally gives a max cabin altitude of 8000ft.

An overboard dump valve is at the forward lower left hand side of the fuselage. It is normally open a small bit throughout flight to to improve forward cabin ventilation. If the outflow valves close then this will close automatically.

3) There is a single probe on the forward left hand side of the fuselage which senses ice formation.

The aircraft has Nacelle Anti-Ice which is not automatic like the 777. Nacelle Anti-ice is hot bleed air. It is used when the temp is below 10 oC.

Wing Anti-Ice is a valve in the leading edge of the wing, when the valve is opened bleed air flows from the engines into a spray tube in the leading edge. In all my time on the 744 I have yet to see it used!

Obviously the windows are heated too

4) 8.9psi

Hope this helps

Best of luck
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