Accident Details
Probable Cause and Findings
A loss of engine power for reasons that could not be determined.
Aircraft Information
Registered Owner (Current)
Analysis
On July 23, 2023, about 1152 central daylight time, a Beech H35 airplane, N365B, was substantially damaged when it was involved in an accident near Georgetown, Texas. The pilot and 2 passengers sustained minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.
The pilot stated that he purchased the airplane about one month before the accident flight. The airplane was flown from California to Texas by a friend of the pilot. About two weeks before the accident, the pilot completed a familiarization flight with the friend who had relocated the airplane to Texas and who was also a flight instructor.
According to the pilot, on the morning of the accident flight, he flew from Georgetown Executive Airport (GTU) to Gillespie County Airport (T82) with two passengers. The airplane’s main and auxiliary fuel tanks were full before that flight; the wing tip tanks were not fueled. The pilot and passengers remained at T82 for lunch before the planned return flight to GTU. The airplane was not fueled while at T82.
The pilot reported that the run-up, takeoff, climb out, and cruise portion of the return flight proceeded normally. While on left base in the airport traffic pattern at GTU, he attempted to increase engine power after configuring the airplane for landing, but the engine did not respond. His attempt to troubleshoot the problem, which included activating the fuel boost pump and changing fuel tanks, was not successful. He notified the airport tower controller of the loss of engine power and the airplane “impacted seconds later.”
ADS-B data revealed that the initial flight departed GTU at 0925 and arrived at T82 about 0959. The accident flight subsequently departed T82 about 1124. The final data point was recorded at 1152 and located in the immediate vicinity of the accident site.
The airplane impacted an unoccupied two-story residence about 1 mile south-southwest of the airport. It broke through the roof structure and came to rest on top of the second story. The airplane sustained damage to the fuselage and both wings.
A postaccident examination confirmed continuity of the airframe fuel system using compressed air from each wing root fuel line through the fuel selector. The fuel selector operated normally when rotated; however, the detents at each tank position were not pronounced as normally expected. The fuel pump drive coupling was intact. The electric fuel boost pump was tested and operated normally. The fuel strainer contained some water, and the screen was partially obstructed with debris. The recovery operator noted that the airplane was stored outside after recovery from the accident site. The fuel tank vents were unobstructed.
An engine test run was conducted following an initial examination and evaluation. The engine started normally, ran smoothly, and responded to throttle inputs promptly. During the test run, the engine speed at full throttle was 2,450 rpm rather than 2,700 rpm as specified for maximum rated power by the manufacturer. The fuel pressure was 18.2 psi, which was above the limit of 17.2 psi. When the fuel mixture to the engine was leaned to a fuel pressure to 16.0 psi, the engine speed measured 2,432 rpm.
Airplane maintenance records revealed that, in August 1986, the originally installed Continental O-470-G engine was replaced with a Continental IO-520-B engine under Supplemental Type Certificate SA686CE. The fuel pump was replaced with an overhauled unit about 18 months before the accident flight. The engine had accumulated an additional 29 hours since the fuel pump was replaced. The maintenance records noted a “fuel system adjustment” at that time. Fuel pressure is a field-adjustable parameter. The maintenance records contained no entries after the annual inspection on January 2, 2023.
Data Source
Data provided by the National Transportation Safety Board (NTSB). For more information on this event, visit the NTSB Records Search website. NTSB# CEN23LA318