View Full Version : Moving controls and A/P in 737NG

04-19-2007, 11:58 PM
We've been battling away with our columns and yokes for the past week, getting them installed, control-loaded, and a mechanical trim mechanism fitted (to simulate electric trim on the elevators). It's taken a bit longer than planned! Nearly there though.

Anyways - we're wondering what happens in real-life when the A/P is engaged and the pilot is hands-off:

1. Do the control columns move fore-and-aft with A/P pitch commands? Or, is it just the trim wheels that move with A/P pitch commands?

2. And a related question ... does the A/P actually move the elevator linkage itself to change pitch, or does the A/P cause pitch changes by moving elevator trim backwards or forwards?

3. Do the control yokes move side-to-side with A/P roll commands?

If anyone is familiar with how things happen in the real Boeings we'd be thankful for some guidance.

Trevor Hale
04-20-2007, 08:10 AM
Hi Nic.

As far as I am aware the controls and yokes move with the autopilot as if your hands were on it.

Best regards.


06-12-2007, 11:05 AM
anyone know how firm the movement is?
I would guess it is very firm, probably beyond manual override without disengaging A/T. Now, that would be a challange...

06-12-2007, 11:37 AM
On any aircraft I know of using conventional controls (ie non fly by wire) the autopilot servos actually move the control cables, so the control column does in fact move with autopilot inputs. After the initial pitch input to the elevators the autopilot then runs the pitch trim to remove the control forces.