Yakovlev YAK 52 N2YK accident near Hillsboro, Oregon

Probable cause

A partial loss of engine power during cruise flight for reasons that could not be determined because postaccident examination did not reveal any mechanical malfunctions or failures that would have precluded normal operation. Contributing to the accident was the pilot's decision to continue flight instead of conducting a precautionary landing at nearby airports.

NTSB analysis

The pilot and passenger were flying the airplane in formation with another airplane on a daytime visual flight rules positioning flight. According to the pilot of the other airplane, while abeam an airport on their route of flight, the accident pilot informed him that the engine had started to "miss" and that they needed to change their destination. As the airplane was south of another airport, the accident pilot informed the pilot of the other airplane that he might have to declare an emergency; however, he did not state the nature of his emergency. The flight continued, despite repeated attempts by the pilot of the other airplane to communicate with the accident pilot with no response. The pilot of the other airplane reported that both airplanes had overflown six airports that would have been suitable for an emergency landing. Ultimately, the accident airplane descended to a low altitude and impacted trees just south of the airport at which the accident pilot had originally intended to land. The airplane sustained substantial damage to the fuselage and left wing. The accident pilot had no memory of the accident sequence or the events that led to the impact with trees and terrain. The passenger recalled that at one point the engine sputtered. Postaccident examination of the airframe, engine, and accessories revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation.

Text from the NTSB. Open the NTSB docket for WPR18LA127 for the full record.