When the throttle stuck at partial power on the takeoff roll the pilot and Instructor pilot of an M20T had no choice but to continue the takeoff at reduced power. Enroute they regained vernier control but were unable to adjust power quickly enough on the flare to avoid a bounced/porpoised landing; which culminated in a prop strike.

Date: 2011-11 · Aircraft: M-20 Series Undifferentiated or Other Model · Phase: landing

Anomalies: aircraft-equipment-problem-critical|ground-event-encounter-ground-strike-aircraft

Synopsis

When the throttle stuck at partial power on the takeoff roll the pilot and Instructor pilot of an M20T had no choice but to continue the takeoff at reduced power. Enroute they regained vernier control but were unable to adjust power quickly enough on the flare to avoid a bounced/porpoised landing; which culminated in a prop strike.

Narrative

At mid field on the take-off roll the throttle froze; it could not be advanced or retarded (push/pull or twist). Neither my CFI nor I could move the throttle. We managed to achieve 72 KTS and became airborne. Not knowing what the problem was and since the plane flew normal it was decided to go to the destination with a longer runway and less traffic and get the throttle checked.The flight enroute went well. The vernier throttle could not be pushed in or out but could be turned to slowly adjust engine speed in flight. We decided not to play with the throttle lest more serious things could go wrong. Over our destination we tried to work the throttle by pressing the center button that was locked in location; but with no luck. We set up a long final approach with an air speed of 82 KTS and 10 degrees of flaps. The landing looked routine with a slight crosswind. Over the numbers we were doing 80 KTS. The sink rate seemed to be a little excessive and so I tried to add a little power to adjust the sink rate. It became obvious the throttle would not move and so we tried to screw-in the throttle but we could not before the landing gear hit the runway and the aircraft porpoised. On the first porpoise the prop struck the runway. Again we could not add or reduce power. We pulled the mixture full out to stop the engine. Later; while still sitting in the cockpit; I played with the throttle for some time with a small pocket knife and the button in the center of the throttle popped out and it had free movement and seemed normal.

Second reporter narrative

Entering downwind gear down; abeam numbers reduced power 17 inches 10 degrees flaps; on final landing power 15 inches speed 80 KTS. When landing was assured; all flaps. Then encountered excessive sink rate; pilot tried to add power but couldn't.

Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.