Problem with altitude hold

This is just a guess but I would say you don't have the plane properly trimmed out for level flight prior to engaging the altitude hold. If you are in climbing trim or you have increased speed since engaging altitude hold it would naturally increase altitude when disengaged.

Even when i press the button to center ailerons etc. before disengaging altitude hold it still sometimes pulls up.

Nero89 Fly's:
-----------------------------------------
Virgin Blue 737-700
Qantas 'Yananyi' 737-800
British Airways 747-400
Atlas Air 747-400

Centering the controls does not trim the plane to fly straight and level. That is done with the trim controls. Again, I'm guessing, but it sounds like you are in takeoff trim which the plane will naturally climb even at cruise power if not trimmed out. I think you need to trim the plane for level flight using the elevator trim control before you engage altitude hold. If properly trimmed it shouldn't climb or descend (except for maybe minor trim adjustments) when you disengage the altitude hold.

i know its not the most professional thing but i dont even use trim. I just, takeoff & climb and then put autopilot on- then disengage autopilot for the final approach. I dont even make any turns by myself except for the ones on approach (and on the ground of course). Therefore i never use trim.

I have experienc ed the same problem. What you'll probably find is that when you take off you select the autopilot straight away. So when you disengage the autopilot, your pitch reverts to what it was on take-off if you follow me. A simple way of avoiding this (thought not strictly speaking correct) is to set the altitude hold switch on the ground and then at about 170kts (in a boeing or similar aircraft) engage the autopilot.

Hope this sorts the problem

Trim is your friend, not your enemy. A properly trimmed aircraft is much easier to fly.

We each get out of FS2004 what we want to get out of it, but I would suggest you go to the lessons section of the flight sim and you will learn more about flying if you are at all interested in learning to fly.

When you select the autpilot, it will trim the aircraft out for level flight.

Some aircraft systems will revert back to the orginal setting before the autopilot was set. For this reason, trim the aircraft for level flight, then set the autopilot.

No it's not the trim at all, this happened to me today with my meljet 777, after asking the ATC to decrease the altitude and decreasing altitude a little, the plane was fine again. I don't really think its anything to do with the trim.

yeah, next time i get the chance i will fly the lessons because now that i think about it, i wouldnt mind having the abilities to do more flying manually, instead of relying on the autopilot so heavily.

Nero89 Fly's:
------------------------------------
Virgin Blue 737-700
Qantas 'Yananyi' 737-800
British Airways 747-400
Atlas Air 747-400