777 Bleed penalties

[Barronflyer]

Hi there

Can anyone explain why the 777 MEL Bleed section incurs so many performance penalties for TO and CLB...e.g. for HPSOV or PRSOV inop....Any info would be appreciated

[mutt]

Because its assumed that the other engine is providing all of the pneumatic demand and is therefore capable of delivering less thrust, that thrust level will then be used for the takeoff calculation.

Mutt