PPRuNe Forums - View Single Post - Shutdown Packs=More power?
View Single Post
Old 5th March 2003 | 16:43
  #2 (permalink)  
Intruder
25 Anniversary
Veteran: Navy
 
Joined: May 2000
Posts: 3,204
Likes: 2
From: Seattle
The full procedure includes running pack 2 from the APU and closing the bleed isolation valves. That way, no bleed air is used from the engines to run the packs.

However, the procedure is not often required on the 744, especially with the GE CF6-80C2-B5F engines. There are few situations where an APU-to-pack 2 takeoff is required (VERY high temperature [>40C] and short runway [<9,000']).

The takeoff performance calculations include required climb performance on 3 engines in the takeoff configuration, so messing around with the pack switches at low altitude after an engine failure would be counterproductive.
Intruder is offline