What happened
On November 24, 2008, a Beech 95-B55, registration N412ES, crashed into a wooded area in Whites Creek, Tennessee, during an instrument flight rules (IFR) flight from Hot Springs, Arkansas, to Nashville, Tennessee. The flight was operating in instrument meteorological conditions (IMC) with rain and mist.
While being vectored for an approach to Nashville International Airport, the pilot began experiencing difficulties. At approximately 10:42 AM, radar data showed the aircraft's heading deviating left of the assigned course. The pilot informed air traffic control that he was "all screwed up up here." Shortly thereafter, the pilot reported that the aircraft was in a spin and that he could not stop it. The pilot also stated he was unable to climb. The aircraft descended uncontrollably and struck trees behind a residence, where a postcrash fire occurred. All 3 occupants were killed.
The investigation
Investigators examined the wreckage and found the left engine had experienced a total loss of power. The investigation focused on the left engine's flexible fuel supply hose, which had separated from the engine-driven fuel pump inlet fitting. This separation was caused by an inadequately torqued B-nut.
Operational testing of an identical engine setup demonstrated that when the B-nut was merely finger-tight, the fuel hose could separate from the fitting during engine operation. Maintenance records showed that while the engines had been replaced with remanufactured units approximately nine months prior, there was no record of the flexible fuel hoses being replaced. The left fuel selector was found in the main tank position, and the left propeller had not been feathered following the engine failure.
Findings
- The left engine lost power due to the separation of the flexible fuel supply hose from the engine-driven fuel pump inlet fitting.
- The separation was caused by the failure of maintenance personnel to properly tighten the B-nut on the fuel supply hose.
- The pilot failed to feather the left propeller and secure the left engine according to the procedures outlined in the Pilot's Operating Handbook.
- The pilot failed to maintain the necessary airspeed, lateral, and directional control of the aircraft following the loss of power, leading to a flat spin.