View Full Version : 757/767 Packs off take-off
757manipulator
6th Nov 2007, 16:28
Can anyone enlighten me as to their specific company SOP's relating to this supplimentary procedure?
I'm interested in comparing my employer's take on this.
reduce to minimum
6th Nov 2007, 17:02
Depending on SB status of the particular A/C (only 767s here) in my company itīs either a) simply Packs Off when entering the RWY, one pack on after climb thrust selected, second pack on when cabin rate stabilized or
b) Packs Off, cabin altitude mode selector MAN, Outflow valve 3/4 open, one pack on after climb thrust, cabin altitude mode selector AUTO, second pack on after cabon rate stabilized
Brgds
Golden Rivet
6th Nov 2007, 17:12
Dont caught out by the "Bleed off" EICAS message.
The two types have totally different procedures for P.O. T-O. Vol I Supp Procedures details the actions for each type.
It was pointed out to me that for the 767 the APU is not sufficient to provide bleed air for both the packs and the ADP. Therefore, for the 767 you cannot do an APU-to-Pack takeoff, because there would not be sufficient pressure to operate the ADP (along withthe packs) if an abnormal occurs. Loss of the ADP is a 40,000 pound hit on RATOW for dispatch for some 767s. For other 767s, I think it is still a 36,000 pound hit.
That's a significant penalty. Look it up next time you are in the jet.