View Full Version : B757 utility buses

fingal flyer
3rd Nov 2007, 01:20
Just wondering why they both go off when apu is running electrics and thrust levers are advanced.IE engines shutdown.Suspect it is load shedding due to a/c logic suspecting double engine failure but can anyboby help an ignorant pilot.

3rd Nov 2007, 01:39
Yes f.f., it is load shedding due “single power source” supplying buses with thrust levers advanced.

4th Nov 2007, 02:00
It's probably like the 767 which loadsheds in the air with a single power source. On the 767, Boeing defined "in air" (wrt to loadshedding) as weight off wheels(bogey tilt) or thrust levers advanced (presumably as a backup for the gear tilt).


4th Nov 2007, 16:24
The CRJ does the exact same thing. It doesn't even have to be in the air. All it takes it to be single-gen, main door closed, flaps out of zero.