Originally Posted by
ustio
Once you decided to taxi with one engine, you let the APU bleed off during taxi. And since bleed 1 only supply pack 1, and bleed 2 is still off because the 2nd engine hasn't been started, it could get quite hot in the back since pack 2 doesn't get any air.
My question is is there any operator that modified the SETO procedure by letting the APU bleed on or open the crossbleed? Is there any effect of turning those on/open during SETO?
My former employer's FCOM SETO procedure for the IAE-engined A320 directs pilots to open the X BLEED after ENG 1 start, so that ENG 1 will supply both packs.The X BLEED remains open until after the second engine start. The APU is left running, but the APU bleed is selected OFF to prevent the ingestion of engine exhaust gases into the air conditioning system.
On the NEO aircraft, the X BLEED is left in AUTO, the APU
may be left running, but the APU bleed is selected OFF as above.