Pilot Operated A V35 Bonanza With "Known Deficiencies," Board Says

The NTSB on Monday released a probable cause report for an accident that fatally injured one person and seriously hurt four others. In this instance, the pilot apparently chose not to believe that his airplane was telling him something was wrong and opted to fly it without having his mechanic look it over. Still, in testing the board was not able to duplicate the loss of engine power reported by the pilot before the plane went down. The pilot was the person fatally injured in the off-airport landing attempt.

NTSB Identification: CEN09FA462
14 CFR Part 91: General Aviation
Accident occurred Saturday, July 25, 2009 in Oklahoma City, OK
Probable Cause Approval Date: 06/20/2011
Aircraft: BEECH V35, registration: N9112S
Injuries: 1 Fatal,4 Serious.

The airplane had a previous history of in-flight engine stoppages, and the engine lost power twice within the week before the accident. The pilot did not have his mechanic investigate the cause of those events, as he believed when the engine lost power the airplane was in a fuel cross feed position, and all he had to do was to switch to a main fuel tank. On the day of the accident the airplane was two miles from the airport after departure when the pilot reported a loss of engine power to air traffic controllers. The pilot executed an off-airport emergency landing to a congested area, adjacent to a major six-lane thoroughfare. The airplane was substantially damaged when it impacted a tree and the concrete base of a light pole, during the emergency landing. The engine was recovered from the wreckage and installed in an engine test cell. It started on the first attempt and ran at full throttle with no anomalies noted. A postexamination of the other airplane systems showed no anomalies.

The pilot had been treated for anxiety, depression, high blood pressure, and obstructive sleep apnea, among other significant conditions. He had been on multiple medications at the time of the accident including at least an antidepressant, a blood thinner and a potentially impairing prescription medication often used for the treatment of chronic pain. The pilot denied any medical conditions or the use of medications in his most recent application for an airman medical certificate. It was not possible to conclusively determine whether distraction or impairment due to his medical conditions or to medication use may have played a role in his decision-making following the loss of engine power.

The pilot’s fatal injuries were likely a result of the impact between his chest and the control yoke. It could not be conclusively determined the extent to which the forward cabin structure and the control yoke in particular were moving aft relative to the rest of the cabin structure following the primary impact with the ground, but it is possible that the likelihood or severity of the pilot’s impact with the control yoke would have been reduced through the availability and use of a shoulder harness.

The National Transportation Safety Board determines the probable cause(s) of this accident to be he pilot’s decision to operate an airplane with known deficiencies, and the loss of engine power during climb for undetermined reasons.

FMI: www.ntsb.gov