Lost Autothrottle

[macpac22 0]

on departure i got an "unable next alt" message in the FMC. since then i have lost the autothrottle and the annunciation in the PFD. Ive tried everything and i cant get the autothrottle back. any ideas?http://www.geocities.com/paulmcmahonie/auto.JPG

[Guest Loiosh]

According to the manual "Autopilot Flight Director"... well, in my case it shows "Autpilot Flight Director", anyways: on page 8-8: "If the autothrottle is armed in flight, but disengaged, it will automatically re-engage if any pitch or authothrottle mode is selected on the MCP."

[downscc 1,327]

"Unable next altitude" is a result of the FMC's projection of an ability to climb to the next constraint based on current conditions. The key is current conditions. This happens to me frequently when I'm in departure configuration and there is a constraint ahead. I'll switch to MCP Speed until cleaned-up then the VNAV and AT will always take it back. The current conditions changed from initial climb to normal climb and the constaint is easily achieved. This is a limitation of the FMC model, but it is relatively minor.

[Guest Stanner1953]

The auto throttle will shut down if the generators are OFF!Go to the overhead panel and down near the bottom are the two generator switches. Turn them on. You will know they are in the off position if the blue light appears next to each switch.Turn on the generator switches (there are two, one for each generator) and you should be ok.Stanner