Accident Summary
On June 12, 2020, about 1000 Pacific daylight time, a Bellanca 7KCAB Citrabria airplane, registration N36339, was substantially damaged in an accident near Renton, Washington. The certified flight instructor (CFI) and the pilot receiving instruction sustained minor injuries. The flight was conducted as a Title 14 Code of Federal Regulations Part 91 instructional flight.
Flight Operations
The aircraft had recently completed an annual inspection, and the accident flight was its first since emerging from maintenance. The operator, Boeing Employees Flying Association, required a test flight following such inspections. The CFI, authorized to perform these flights, chose to include the pilot receiving instruction, who was working toward her tailwheel endorsement. The test flight protocol included an extended checklist with an elongated preflight and runup.
Before departure, the CFI added 10 gallons of fuel to each wing tank. Engine start and runup were normal. With the pilot receiving instruction in the front seat, she performed the initial takeoff from runway 16. The aircraft remained in the traffic pattern for touch-and-go takeoff practice and landings.
Power Loss and Off-Airport Landing
After an uneventful three-point landing, the pilot receiving instruction applied full throttle. The airplane accelerated to about 400 feet above ground level when the engine abruptly stopped producing power, though the propeller continued rotating. The CFI decided to land on an access road. During the off-airport landing, the airplane collided with a tree, resulting in substantial damage to both wings and the fuselage. The aircraft came to rest in a vacant construction company storage area.
The CFI stated that the airplane was too low for him to check instruments or troubleshoot, and from the rear seat he had limited visibility of the engine gauges. The pilot receiving instruction reported that immediately after the power loss, the CFI asked what was happening. She confirmed that the throttle was fully forward, the mixture was rich, and the fuel selector valve and boost pump were in the ON position.
Postaccident Examination
During postaccident examination, investigators found a piece of paper, approximately two by three feet, bunched up inside the air induction box. The paper was white with a plastic-type coating and appeared to have mostly restricted the inlet cavity. No other anomalies were noted.
Maintenance History
The lead mechanic who performed the annual inspection stated that the inspection included a repair for a hole near the exhaust on the lower cowling. He hired a local repair person to complete the fiberglass work and painting. After maintenance, the airplane sat for a day with the lower cowling and air filter removed. Once the work was finished, the lower cowling was reinstalled, and the mechanic completed a final inspection and a post-inspection run-up with no discrepancies noted.