PIPER PA-24-250 — Truckee, CA

What happened

Two witnesses who were onboard the airplane during an attempted takeoff before the accident flight stated that, during the takeoff, the airplane appeared to accelerate and lift off normally. However, as the airplane climbed about 20 feet above the runway, it wobbled to the left and right and drifted slightly to the left. The pilot subsequently aborted the takeoff. Upon returning to the terminal, the pilot had both passengers exit the airplane, and he then taxied back to the active runway.

During the second attempted takeoff, several witnesses observed the airplane begin a normal takeoff roll, lift off about one-third of the way down the runway, and enter a nose-high attitude. The airplane was observed rotating back and forth along its longitudinal axis before entering a steep right turn. Subsequently, witnesses observed the airplane descend into an unoccupied hangar. All of the witnesses reported that the engine sounded normal and appeared to be producing power during the takeoff and accident sequence.

Postaccident examination of the accident site and airplane wreckage revealed signatures consistent with a near-vertical impact with the hangar. Examination of the airplane, flight control systems, engine, and propeller revealed no evidence of any preimpact mechanical malfunctions or failures that would have precluded normal operation. At the time of the accident, the airplane was within weight and balance limitations.

Review of the pilot's personal primary care medical records revealed treatment for shift-work sleep disturbance with zolpidem and treatment of hypertension with valsartan. On each visit, the primary physician recorded that the pilot reported no use of drugs or alcohol. Postaccident toxicology testing revealed positive results for losartan (also used to treat hypertension), zolpidem, and buprenorphine, which is a controlled substance used to treat severe pain. The pilot's primary care medical records did not mention acute or chronic pain or its treatment. Buprenorphine carries a warning from the Federal Drug Administration that it "may impair mental and/or physical ability required for the performance of potentially hazardous tasks (e.g., driving, operating heavy machinery)." Further, opiates cause, in part, sedation, alterations in cognitive and sensory efficiency, respiratory depression, nausea, vomiting, headache, and sleep and concentration disorders. With chronic use, tolerance can develop, which mitigates the drug's effects. Several issues made the interpretation of the toxicology report difficult. Opioids may undergo postmortem redistribution, which may result in postmortem levels not directly reflecting antemortem levels. In addition, depending on the pilot's pattern of use, it is possible that he had some degree of tolerance for the drug's effects. Further, his actual dosing interval may not have been the same as the dosing interval noted on the prescription bottle found in the airplane. Thus, it was not possible to determine the exact effects of the drug on the pilot at the time of the accident. In addition, the effects of the underlying chronic pain syndrome on the pilot's performance are unknown. However, it is likely that the pilot was using a significant amount of opiate medication at the time of the accident, and, therefore, that he was impaired to some degree as a result.

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