A question about aircraft pitching!Please help!

[wolfking_liu 0]

Hello everyone, I am a newly registered user today and I have a question about aircraft pitch!

When I press the nose up key,the elevation angle of the aircraft increases normally,but when the aircraft reaches a certain speed,I release the nose up key,the elevation angle of the aircraft is still slowly increasing,in other words when the aircraft reaches a certain speed,I release the nose up key,the elevator cannot be fully reset!The same thing happened when I press and release the nose down key!Why?

The speed at which this phenomenon occurs varies among different aircraft,so I think this should be related to the pneumatic parameter settings in file data.ini.How to set up to eliminate this phenomenon？