Light Sport Aircraft
Flight Crew Instrument; Flight Crew Commercial
Flight Crew Last 90 Days 30; Flight Crew Total 3972; Flight Crew Type 472
Situational Awareness
Aircraft Equipment Problem Critical
Air Traffic Control Provided Assistance; Flight Crew Landed in Emergency Condition; Flight Crew Diverted; Flight Crew Inflight Shutdown; General Declared Emergency; General Maintenance Action
Aircraft; Human Factors
My airplane is a RANS S-19 special light sport with a Rotax 912 ULS engine. I departed with flight following and climbed on course. At about 4;500 feet; when I tried to throttle back; I could not. Throttle would only come back about half way and as speed increased engine RPM was in yellow zone which is to be used for no more than five minutes. I told Approach the problem and told them I would have to divert. Approach vectored me to ZZZ; which was clearly visible; gave me altitude at my discretion and asked if I needed assistance. I said yes. Switched to Tower; I chose Runway X which was favored by the wind and alternately gliding and restarting the engine. I entered right downwind to Runway X and using no flaps landed on Runway X and with two more bursts of power I rolled off the runway to taxi where crash truck awaited. Tower sent FBO to tow me back to ramp. Taking off cowl; I could see that a throttle cable was snagged on an upright bolt. I believe the cable had become loose at the other end so it could loop over the bolt. Professional help by Approach and Tower made for a successful outcome of a tense situation. In retrospect; I should have asked to climb higher until closer to the field and then shut down engine completely.
LSA pilot experiences a jammed throttle linkage while attempting to level off resulting in higher than desired airspeed and engine RPM. The reporter is vectored to a suitable diversion airport with the engine being shut down and restarted several times to maintain altitude and then to taxi clear of the runway.