Reading that I'd say you determine all performance data based on 'packs auto', than check that the resulting V1 is higher that Vmcg for packs off.
You're combining two worst cases. Single engine T/O performance with the operating engine running a pack (lowest thrust of the two), and single engine controllability when the operating engine is not running a pack (highest thrust of the two).
Quote:
| So if you do this configuration, you operate the left pack from the Apu, and you can do just an engine bleeds off calculation. Am I getting this right? |
Correct
Quote:
| So you don`t have to takeoff with one pack operating by engine bleeds, except you`re APU is broken, right? |
Correct. But if you have enough performance available, why would you?
Just checked our DDPG (B738) and it says:
Quote:
When dispatching with a single pack on for takeoff (airplane pressurized), VMCG should be determined based on AC packs OFF.
Takeoff performance should be based on AC packs ON/AUTO. |