Beacon Light
 

Would like to when the rotating Beacon light on top and bottom of the aircraft can be switched On.
For example an airline that I know wants the pilots to switch On the beacon before commanding the cabin crew to arm slides. As I understand the beacon is switched On only after the ATC clears to start engines so that personnel/vehicles in the vicinity are aware. If it is switched On before that it may bring vehicular traffic around it to a halt needlessly.
Any documentation in this respect will be appreciated. thanks.

Does it really matter?

I guess so. What if a pilot switches on the Beacon when he is not even ready to commence push-back and stops the vehicular traffic behind his aircraft.

Suggest in the example you've given, that the pilot waits until ready for push back and start, requests clearance from ATC, informs CC to arm doors, turns on beacon, runs the starting checklist.

Massage the order as required to fit with other SOPs, but I see no reason why the beacon must be on before the pilots are ready to go.

If the beacon is on, the pilots are ready to go, and all vehicles must bugger off.

It's not like the whole airport operation stops when a plane turns on the beacon.
Beacon on when arming the slides even makes sense.
Tells the ground personnel to stay away from the doors.
Slide deployment will kill when it drops.

Clear to start and or push, Beacon on........checklist done. Ground crew get out of the way.
Cabin crew arm doors when the Jet moves, its been done that way for years.

It's not Rocket Science.

Scat, what you/we do and what the AFM says are ... ;)

You obviously have not operated into Edinburgh, UK :}

Beacon on/off is a clear signal to ground crews that certain activities are restricted, and the danger area around the aircraft is increased, on arrival it usually means the only things that can approach the a/c is GPU and headset man, on departure it's the two preceeding plus airstart, and yes all ground vehicles should not pass behind.. akindofmagic you need to understand how dangerous a ramp can be,

Fully aware, thanks. My point was: have we really got to the point where people need to be told exactly when to put the beacon on? Isn't "at an appropriate point before engine start" sufficient?