Accident Details
Probable Cause and Findings
The pilot's failure to properly assemble the fuel pump, which resulted in the loss of fuel pressure and the subsequent partial loss of engine power.
Aircraft Information
Analysis
On September 22, 2016, about 1400 central daylight time (CDT), a Vans RV9A experimental airplane, N699RV, was substantially damaged during a forced landing near Cushing Field Ltd Airport (0C8), Newark, Illinois. The private pilot was not injured and the passenger suffered minor injuries. The airplane was privately registered and operated under the provisions of Title 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed for the flight, and no flight plan was filed.
The pilot and passenger were conducting a cross-country flight when the pilot observed the fuel pressure fluctuating, and the engine began sto surge. The pilot turned on the backup fuel pump; the engine continued to surge so he diverted to 0C8. The pilot stated he had difficulty maintaining visual reference to the airport and the airplane was losing altitude as he circled over the airport. The pilot performed an "S" turn and found he was still too high. He was running out of runway below him, so he performed a "hard slip" to lose altitude. The airplane stalled 10-15 ft above the runway, hit the ground, and slid about 30 ft before stopping.
The pilot reported he conducted a flight four days before the accident, on September 18, and he felt a "couple small pauses in the powerplant." The engine quit after landing and did not restart until the auxiliary fuel pump was turned on. He subsequently tested the primary fuel pump, which did not work, and ordered a new fuel pump. When the new pump arrived it did not have the bottom fitting attached, whereas the previous replacement was fully assembled. The pilot took the fitting off the old pump and there was an O-ring present; however, he did not see an O-ring with the new pump "kit." He said the mating surfaces were different between the two pumps and the new pump did not appear to require an O-ring. Additionally, the instructions that came with the new pump did not mention an O-ring. The pilot installed the new fuel pump without an O-ring and conducted a successful test of the new pump.
Following the accident flight, the pilot questioned whether there could have been an O-ring accompanying the new fuel pump that he had not seen. He examined the area where he performed the maintenance and subsequently located a 5/8" O-ring inside another component that came from the box containing the new pump. The pilot stated the accident was caused by this maintenance issue.
Data Source
Data provided by the National Transportation Safety Board (NTSB). For more information on this event, visit the NTSB Records Search website. NTSB# CEN16LA387