WPR21LA140

The pilot reported that, shortly after takeoff, at an altitude of about 100 ft above ground level, the engine began to sputter. The pilot initiated a left turn, to land on the smaller parallel runway to the east. During the turn, the engine lost all power, and the pilot was unable to maintain altitude. The airplane collided with trees and came to rest about 500 ft east of the runway. A postaccident examination of the airframe, engine, and fuel system revealed no evidence of a mechanical failure or malfunction that would have precluded normal operation. The reason for the loss of power was not determined.

On March 23, 2021, about 0900 Pacific daylight time, a Cessna 172S airplane, N2164Z, was substantially damaged when it was involved in an accident near Everett, Washington. The pilot sustained minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot reported that he planned a flight from Paine Field (PAE), Everett, Washington, with the intended destination of Yakima, Washington. After completing a preflight check and verifying the fuel quantity was nearly full in each wing tank, the pilot taxied to the runway. During the takeoff roll, the airplane accelerated to about 55 knots, at which point he began the initial climb. Several seconds later, at an altitude of about 100 ft above ground level, the engine began to sputter and felt like it “choked”. The pilot initiated a left turn to land on the parallel runway to the east. During the turn, the engine lost all power, and he was unable to maintain altitude. The airplane collided with the trees and came to rest about 500 ft east of the threshold for runway 34L. Throttle and mixture control continuity was established from the cockpit controls to the fuel servo and moved from stop to stop when actuated by hand. The mixture control cable was separated from the rod end, which remained attached to the fuel servo mixture arm. The damage to the mixture control cable was consistent with impact damage. A visual inspection of the fuel system revealed that continuity was established from the main fuel tanks throughout the system to the gascolator fuel fitting at the firewall. When the electric fuel pump was turned on, fuel expelled from the fuel fitting at the firewall. A visual inspection of the gascolator fuel revealed minor debris. The fuel was tested for water finding paste, with negative results. The engine’s crankshaft was rotated by hand, and continuity was established throughout the engine and valve train. Examination of the cylinders with a lighted borescope revealed no anomalies. Subsequent examination of the fuel flow divider and servo did not reveal any mechanical failures or malfunctions that would have precluded normal operation. Examination of the mechanical fuel pump revealed that, the oil diaphragm had cracking along the outer edge and a tear about ½ inch in length was observed near the center. Oil was observed in the compensator diaphragm chamber; however, the fuel diaphragm was intact, and the fuel valves remained in place and both where unremarkable. The manufacturer reported that the tear and cracking on the oil diaphragm would not have an adverse effect on the engines ability to produce power. Examination of the recovered airframe and engine did not reveal evidence of any mechanical anomalies that would have precluded normal operation.