What about autoland using GPS?
A/T would primarily be to maintain the correct landing speed.
The NTSB said they had good steady speed of 161mph, so it appears the autothrottle was working.
If they weren't using GPS, they'd need some way of inputting altitude control based on what they saw from the PAPI while everything else was automated.
18 was only rated for non-precision approaches, which includes GPS.
GPS alone doesn’t give you accurate enough altitudes, iirc.
It just gets you to the runway.
They were using the Localizer as far as I know, and not GPS.
A steady throttle would mean they didn’t do anything after hitting the trees.
One would expect them to initiate a go-around.
Hard to believe they didn’t realize they hit the trees.
http://en.wikipedia.org/wiki/Takeoff/Go-around_switches