Don`t speed up game. It cause UAV losing control

I do not speed up the game at all. I play the game in real time. Perhaps it's because we were in multiplayer?

It also loose control if you set Destroy WP is too close from where UAV flight at moment when you place that WP.
It also might be conflict with other mod and multiplayer mode.

Nope, this is not a conflict. This is the physics and handling of the drone.

Even if I set the waypoint several miles away from where I spawned the drone, this can still happen. In fact, more flight time makes it more likely to happen. Some of the drones, on the way to the target, will occasionally front flip or back flip while trying to overcorrect for terrain.

This problem gets worse if the mission is experiencing a poor frame rate. Yeah, I know, that's partly my fault, but the drones should still probably have their maneuverability nerfed just a little bit so this stops happening even when the server isn't performing well or has bad ping.

For example, a similar issue is found in Pook aircraft and other mods because the sensitivity of the controls is too high. Pook never fixed this in his mod so this is still a problem. Now this isn't to say I have Pook's aircraft and your mod running at the same time and they somehow cause a conflict. That's not what I mean. I just mean your aircraft has a similar bug, and the cause of it is just that the drone can pitch too strongly.

Hopefully that all makes sense in translation. You just don't need the drones able to pitch this steeply. If it's not the pitch, then it could be the values controlling air lift that need tweaking.