N581U

On March 8, 2020, about 1015 central daylight time, a Beech V35, N581U, was substantially damaged when it was involved in an accident near Destin, Florida. The private pilot and passenger were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

The cross-country flight was expected to take about three hours. The airplane was refueled the day before the accident to fill both fuel tanks for 80 gallons total fuel. Of the 80 gallons onboard, 74 gallons was usable and provided for about 4 ½ hrs of flight time. After an uneventful preflight and runup, the pilot departed and climbed the airplane to a cruise altitude of 9,000 ft mean sea level (msl). He reported that he switched the fuel tanks every 30 minutes and his fuel burn was about 16 gallons per hour enroute, which should have left him with over 20 gallons remaining when he arrived at the destination.

While on a 5-mile final approach to the destination airport, the pilot conducted a pre-landing check, which included switching the fuel tanks. About 1 1/2 miles from the runway, the engine lost total power. According to the pilot, “there was no sputtering and coughing” and the propeller continued to “windmill.” The pilot attempted to troubleshoot by switching the fuel selector again, checking the magnetos, ensuring the mixture was rich and attempted an engine restart, but was unable to restore engine power. The airplane descended and impacted trees immediately adjacent to a residence, about 2,000 ft short of the runway. The airplane came to rest in the trees in a nose-down, 60° left bank. The pilot could not recall which fuel tank was selected when he switched the fuel tanks during his initial approach checks and after the loss of engine power, and he did not remember turning on the boost pump.

According to the pilot, this was the second time in the previous 12 months where the engine unexpectantly “quit” on final approach. He landed safely the first time and was able to restart the engine after landing. The pilot told a Federal Aviation Administration (FAA) inspector that he had a mechanic examine the airplane after that occurrence, but a reason for the loss of engine power was not found.

A JPI 700 Engine Data Monitor was retrieved and downloaded, revealing that the accident flight was about 3.24 hours in duration. During the flight, from takeoff to the loss of engine power, no anomalous exhaust gas temperature (EGT), cylinder head temperature (CHT), or oil temperature indications were noted. Fuel flow during takeoff was about 25 gallons per hour (gph), during climb was about 19.6 gph, and during cruise was about 16.5 gph. During descent and approach, at about 1012, there was a simultaneous decrease in EGT, CHT, and fuel flow. Fuel flow dropped from 14 gph to zero over the course of 12 seconds and did not resume.

Post-accident examination revealed that the left wing was severely deformed, bent upwards, and was resting on the ground but still attached to the airframe. The right wing remained attached to the airframe but had significant leading edge crushing damage at the wing root. It was oriented in a nearly vertical position. Two propeller blades remained relatively intact and displayed no damage. One of the three propeller blades was slightly curled at the blade tip. The left wing fuel tank was ruptured and did not contain any evidence of fuel. The right fuel tank, which had been positioned nearly vertical, was void of fuel. The fuel selector was positioned to the left fuel tank. Several ounces of fuel were observed in the gascolator, and it appeared clean, clear, and was tinted blue. The pilot reported fuel leaking from the right fuel tank following the accident, and the FAA inspector who responded to the scene reported an odor of fuel after the accident. Subsequent examination of the engine and accessories revealed no irregularities. The propeller was rotated through several rotations and compression was noted in the cylinders. An external fuel source was supplied, the engine was primed and started without hesitation. The engine was operated through several cycles of various power settings, and was increased to full throttle with no anomalies noted. There were no mechanical irregularities with the engine that would have precluded normal operation.

According to the pilot operating handbook, the emergency procedures for an engine failure after liftoff and in flight included:

1. Fuel Selector Valve – Select other Tanks (Check to feel detent)

2. Auxiliary Fuel Pump – ON

3. Mixture – Full Rich, then Lean as required

4. Magnetos – Check Left and Right, then Both

5. Alternate Air T-handle – Pull and Release.