Originally Posted by
SASless
So which came. first....the Chicken or the Egg?
The Crew reported a very serious electrical fire AND a loss of Collective Control AND Dual High Side failures which did not respond to the ECL's and had to be controlled by switching back and forth between Flight and Idle....... am I understanding that is what they reported correctly?
For Coyote,,,,,had they confused the BAT MAIN and BAT MASTER switches.....what would be the result if they somehow switched BAT MASTER to OFF rather than BAT MAIN OFF?
Likewise....what if they had gotten it right and did as the procedure calls for....and turned BAT MAIN to OFF....what would have happened (re instrumentation and controls?
With no generators online at this stage of the electrical fire/smoke checklist, switching BATTERY MASTER off instead of BATTERY MAIN will result in a complete lost of electrical power and cockpit will go black. Bad Juju if you are IMC. The engines however produce power via the PMA which should keep the EEC's running in AUTO.
Switching BATTERY MAIN off as per the checklist, will result in the loss of all but the DC ESSENTIAL busses. Copilot screens, both MCDU's, MAU1 and AP1 lost amongst a host of other stuff. Pilot screens, ESIS and AP2 with ATT remain to keep it flyable IMC.
Flight controls, aside from auto flight and SAS, should be otherwise unaffected by electrical power loss. If they had loss of collective control, it must have been mechanical failure in my view, and I don't think they would have survived.