737;power to the buses....
Evening everyone,
Ok, ive just started my PPL, im also learning the 737 CBT and FCOM material.
At the moment im studying the APU and electrical systems.....
i understand that the 1 & 2 buses need a power source at all times from one of three sources;
-APU
-External power
-IDG
I work at manchester airport and often witness aircraft coming onto stand unable to turn their engines off persumably as no ex pwr is connected, but why isnt the APU running pre coming on stand?
also when ex pwr is connected, why isnt the APU turned off straight after? the flightdeck has now got an alternative pwr source, is this down to the crew not realising ex pwr is available?
hope a more experienced person cany help,
cheers scott