Hi i'm slowly getting the hang of the FMC, however just before take off sometimes i can't switch the auto-throttle on, and some times i can why is this?? I sometimes get a red warning light (A/T) on the main panal and i can't get switch the auto throttle on.. which is a pain after you put all the info into the FMC... any ideas? i got my bird sitting on 22R of JFK so I hope i get a fast answer........

THANKS!!!!!

You need to make sure that you go through the start-up routines as specified in the manual, as the switch positions will define whether specific functions will work, like the autothrottle, or even the engine start-up. If you go through the correct sequence on the overhead panel, then the AT should switch on. My habit with the PMDG 737s is to go through the overhead routine, and then switch the flight director, autothrottle and autobrake on before I program the FMC.

If you use this short checklist, the AT will turn on as I described above:
- Battery and standby power switches on
- APU on and then APU GEN switches on
- DC selector to BAT, AC selector to APU GEN
- Hydraulic pumps and fuel pumps on
- Isolation valve and APU bleed valve open

Hope this helps.

Make sure the Generators for both engines are on, so you are NOT running from APU or GND power.