PIPER PA-12 — Burlington, WA

What happened

The pilot was nearing the completion of a rebuild/restoration of the airplane, but it had not yet been inspected and signed off by a mechanic with an Inspection Authorization. On the day of the accident the pilot was planning on doing a test run of the recently overhauled engine. Witnesses reported that the pilot ran the engine for about five minutes and then shut it down. Then, about fifteen minutes later, he started the engine again and taxied out to the active runway. Without performing a magneto or carburetor heat check, the pilot pulled onto the runway and added what sounded to witnesses like full power. The airplane then made a "very short" takeoff roll before lifting off. Although the liftoff appeared normal to the witnesses, soon thereafter the nose of the airplane pitched up to a near-vertical attitude. It then climbed to an altitude of between 150 to 200 feet above ground level. Then, with the engine still at what sounded like full power, the airplane slowed, fell off on the right wing, and descended near vertically into the grass-covered terrain near the side of the runway. A postaccident teardown inspection found that the elevator control cables had been connected to the incorrect elevator control horns, resulting in a reversal of control inputs at the elevator. A mechanic who had signed off many of the pilot's previous rebuild projects stated that he had found reversed control cables on two other airplanes the pilot had completed. The mechanic also stated that the pilot had done "high speed taxi tests" on a number of other rebuilt airplanes prior to the time they were inspected and signed off. The mechanic had warned the pilot about the dangers of doing so, but the pilot had continued the practice.

Toxicology testing of specimens from the pilot was consistent with the recent use of a medication containing diphenhydramine, an over-the-counter impairing antihistamine. Family members described a 10-year history of a skin condition consistent with chronic urticaria (hives) that resulted in severe recurrent itching and which had frequently occurred while the pilot was working on aircraft. The pilot had not indicated any conditions or medication use at the time of his last Application for Airman Medical Certificate, less than 5 months prior to the accident. Although the pilot likely would have had no opportunity to recover the aircraft once it became airborne, it is possible that impairment from the use of diphenhydramine or distraction from chronic urticaria contributed to the pilot’s failure to correctly rig the elevator cables. However, the investigation could not determine whether impairment or distraction played a role in the accident.

An editorial "what led to it / how to avoid it" analysis for this accident is generated separately and will appear here.