On May 6, 1993, a Cessna 140 (registration N76194) was involved in an aviation accident near Ramona, CA. Investigators recorded the probable cause as: A JAMMED CONTROL YOKE. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
During takeoff in a tailwheel airplane, the control yoke jammed full aft after liftoff. Both occupants applied forward pressure without success. The pilot reduced throttle and the airplane landed hard. Examination found the yoke jammed against the aluminum pitot static line.
Incident
During the takeoff phase of a tailwheel-equipped airplane, the pilot allowed a passenger to handle the control yoke while the pilot maintained control of the rudder pedals and engine power. Shortly after the airplane lifted off, the control yoke became stuck in the full aft position. Both the pilot and passenger applied forward pressure on the yoke, but they were unable to move it from the jammed position. The pilot then retarded the throttle, and the airplane subsequently landed hard.
Examination
Following the incident, an examination of the airplane's flight control system was conducted. The inspection disclosed that the control yoke had jammed against the aluminum pitot static line. The pitot static line, which is part of the airspeed indicating system, was located in a position that interfered with the yoke's movement. The jam occurred when the yoke came into contact with this line, preventing it from moving forward from the full aft position. No additional information was provided regarding any other potential factors or findings from the examination.