My 737...
If you read the above posts, you will see it is not possible to <<If the CC arrive at a the A/C with no power, as happens quite often, can they now throw on the BAT and put the GND PWR on line, arm the Emergency Exit lights and start boarding? I think not. >>
<<What about defects that are written up in the tech log, where the MEL would ground the A/C or even not allow pax on board>> Latter - such as? Former - OK, but for the 0.01% chance that applies, is is not worth having the [i]ability and procedures[i/] to do so, if deemed appropriate. For those of us on "hub" type operations, is it really worth delaying a flight for an extra 30+ mins because you have aircraft, Pax, Engineers, refueller, but Flt Crew late inbound on another flight?
As alluded to above, it rarely works out we use this "ability", but that is no reason not to say it should be forbidden...
<<Asking for trouble in my opinion.>> As also stated above, has been in place with one of the major UK carriers for at least 12 years, if not much more (probably dates back to BEA!). So whilst concerns are always worth expressing, we are not discussing something "new".
NoD