Hi, im new to this forum.

It's been a while since I did my last RC plane flight.
Im having a problem with my multiplex Heron after I hit a tree.

It got stuck in the tree and I couldn't grab it (the tree was like 12-15 meters high) (rough calculation) so I couldn't get it out.
The cockpit, and wings fell of and they were basically gone (there were multiple trees and it basically came to a full stop after it got to the third tree).

After the crash I turned off my transmittor but the plane started it motor and went to full speed. It basically destroyed the propellers (blades).

I eventually got the main body off the plane out of the tree and a couple days later someone brought me the wings and cockpit, they fell out the tree because of the wind).

My plane got out pretty good because it was a really nasty crash.

The problem is, whenever my transmitter is on 0% throttle the plane still goes at 10% and I changed no setting, it worked fine before.

The dangerous thing is (and really annoying) I can't turn off the plane without taking the battery out once its on!

When I turn off my transmitter the plane goes haywire and goes at full trottle wich is pretty dangerous since it can hurt someone/ me.

I haven't flown with it ever since because I don't know how to fix the problem. Ive tried changing some settings in the transmitter and it sort of worked.
I can turn off the motor WHILE the transmitter is ON but I can't go full throttle because it goes into negative (-100%) throttle when it is supposed to be at 0%.

And the plane still goes full throttle when the transmitter is off!!!!

This was really painfull because it took us and hour and a half to get the plane out of the tree and I got out of range to get a ladder so the plane started to destroy itself while it was cutting the tree.

Does anyone knows what causes the problem? Because I can't find anything and I don't know what to replace.