Aircraft elevator trim response with throttle changes

1st Official Post

    A newbie issue here. With various planes i'm finding unexpected effects when I change throttle settings in flight. For example, with the Cessna 172 when I reduce throttle in flight the nose wants to pull up, and I need constant forward stick to maintain level flight. When I increase throttle it's the reverse. With other planes it is sometimes the opposite situation.

    I've been flying R/C planes for the last 40 years, so I know that's not normal, I must have something set up incorrectly.

    I would appreciate any advice to straighten me out!?(?(?(

    • Official Post

    Expected behavior: When you increase throttle and engine power the nose goes up, if you decrease throttle and engine power the nose goes down.

    If that is not the case in the Cessna please double check your control assignments and make sure elevator trim is not assigned or at least not assigned to the same input as throttle. Boeing aircraft also have this tendency, here power or thrust changes also affect the pitch attitude of the aircraft and the flight path changes over time.

    Airbus aircraft have fly by wire and maintain the current flight path. So when you increase thrust the aircraft needs to pitch down to maintain the same lift force to stay on the current trajectory (1g flight hands off). Here thrust is used to control speed where as the flight path remains the same.

    Regards,

    Jan