Hi all, just wanted to ask, when I fly a 747 in AP, it goes great, climbs to assigned altitude, and holds speed ect ect, however when I took a 737 for a flight on AP, after a while, the nose went straight up and aircraft stalled.

Why is this??, I noticed that with the 737 AP, there is a Wing Leveller Switch, does this need to be set to keep aircraft going at correct settings ?
Also notice  L & R Auto Throttles, why is this?

Maybe stupid questions, but hey thats what the forum is for.

Thanks for any feedback.....Tomcat61

I can think of 2 reasons that a 737 would stall while on auto-pilot:   1. If you have the auto-throttle engaged and the speed still set to 0 (or way too low)...the auto-pilot will keep pitching up,,trying to hold altitude, but won't increase the throttles unless a proper "speed" (say 320 kts) is entered.   2. Sometimes (I think it's a bug) if you "over-fly" the auto pilot (climb or descend too quickly) the pitch-trim will go nuts on you and try to climb (or dive) out of control...but this happens on all planes,,not just the 737.. 

I'd make sure you have a proper speed dialed in before engaging the a/s-hold and/or auto-throttle...I think that's your prob.

the AT L&R is the button for the auto-throtlle. when both on, the A/P will control the throttle itself. it's necessary to put this on when you insert a certain speed in your A/P. without engaging the auto-throttle, you can't set a speed in that box.