Introduction
A pilot who was not instrument-rated filed an IFR flight plan and departed into low instrument meteorological conditions without requesting or receiving a weather briefing. Shortly after takeoff, the pilot reported that he was returning to the airport but did not state a reason. No emergency was declared. In a subsequent transmission, the pilot said he had 'the problem resolved' and was continuing to his destination.
Flight Details
Witnesses reported that the engines were 'revvying' and 'unsynchronized,' and that the propellers were being 'cycled.' One witness observed brownish-black smoke trailing from the right engine. The aircraft subsequently struck a ridge, then catapulted approximately 1,000 feet before striking a second ridge. A post-impact fire ensued.
Investigation Findings
Examination of the propellers revealed high rotational damage. Disassembly of the engines, propellers, turbochargers, and various components did not disclose what may have prompted the pilot to want to return to the airport. However, internal components of the right engine were black and, according to a Textron Lycoming representative, were indicative of 'an excessively rich mixture.'
Pilot Background
The pilot had recently been treated by a psychiatrist for depression, attention deficit disorder, and bipolar disorder. He also had a history of alcohol and drug abuse.
Toxicology Results
Postmortem toxicology testing disclosed the presence of Fluoxetine (an antidepressant), Norfluoxetine (its metabolite), and Hydrocodone (a commonly prescribed opiate).