Incident Details
The pilot/owner and three non-pilot acquaintances decided to fly to another airport for lunch. The pilot had owned and operated the airplane for about 10 years and reported approximately 550 hours of total flight time in that make and model. His normal procedures included hangaring the airplane and using a yoke-mounted iPad mini for in-flight information.
Sequence of Events
The outbound flight was uneventful. After landing at the destination airport, the pilot installed the flight control lock in the pilot-side yoke shaft. Following lunch, the four persons returned to the airplane for the return trip. The pilot reported that the preflight inspection and taxi to the run-up area were normal. During the before-takeoff checks, he noticed that the two fuel tank gauges indicated different quantities, which was unusual for the high-wing airplane. He decided to interrupt the before-takeoff check process, shut down the engine, and physically measure the fuel tanks to accurately determine the total fuel quantity. After measuring the fuel and determining it was satisfactory, he re-boarded the airplane, restarted the engine, and taxied from the run-up area onto the runway for departure.
The airplane lifted off about halfway down the 3,600-foot runway. When it reached approximately 20 feet above ground, it stopped climbing. The pilot immediately recognized something was wrong, aborted the departure, and landed on the remaining runway. He was unable to stop the airplane on the runway, and it sustained substantial damage to the fuselage. None of the occupants were injured.
Investigation Findings
After the accident, the pilot determined that he had left the flight control lock installed for the takeoff. The pilot reported that he normally used the airplane manufacturer's checklists on all flights, including this one, but evidence contradicted that account. The manufacturer's checklists explicitly specified that flight controls be checked for freedom of travel during two separate pre-departure phases: the walk-around preflight inspection and the before-takeoff operational checks. For undetermined reasons, the pilot omitted those items from both phases, depriving himself of two opportunities to detect the control lock.
Investigation revealed that the manufacturer-issued control lock had been installed backwards by the pilot, which prevented it from accomplishing one of its primary design functions—inhibiting pilot access to the ignition switch. Further investigation revealed that the pilot rarely used the control lock because he hangared his airplane, and he was unaware that he had installed it backwards. The yoke-mounted iPad limited the pilot's view of the installed control lock, reducing the potential for visual detection. The pilot reported that the winds were "light," which reduced the likelihood of flight control inputs being needed on the ground during taxi, thus depriving him of another opportunity to detect the locked controls. After his impromptu fuel measurement, the pilot did not recommence the interrupted before-takeoff checklist from the beginning, missing another opportunity to detect the locked flight controls.