North American/Aero Classics P 51 N251PW accident near Cummings, Kansas

Probable cause

The loss of airplane control while maneuvering at low altitude for reasons that could not be determined.

NTSB analysis

The pilot and the pilot-certificated passenger departed on a local flight, and the airplane was seen performing aerobatics before the accident. A witness then saw the airplane fly low over the ground, pitch up at a steep angle, turn, descend, and impact the ground in a near vertical attitude. Ground scars and damage to the airplane were consistent with the airplane impacting trees with the right wing, and then the ground in a nose-low, wings-level attitude with a pitch in excess of 60° nose down. According to radar data, the airplane lost about 1,000 ft in altitude during the final 5 seconds of the flight; the rate of descent was about 12,000 ft per minute. The location of the accident was within 250 ft of the last known radar target.

The airplane wreckage was severely fragmented and all damage to the airframe, engine, propeller, and flight controls was consistent with a high-speed impact. Examination of the airframe, engine, and related systems revealed no evidence of any anomalies that would have precluded normal operations.

After performing in an air show the day before the accident, the pilot had agreed to take the pilot-certificated passenger for a ride in the airplane before he departed the area. The airplane was equipped with dual flight controls and it could not be determined who was manipulating the flight controls just before or at the time of the accident.

The pilot's autopsy revealed evidence of previous damage to his heart tissue, and this placed him at risk of a sudden cardiac event such as a heart attack or dysrhythmia. Such an event would likely cause acute symptoms such as chest pain, shortness of breath, palpitations, or loss of consciousness, and sudden impairment or incapacitation could result. However, although such an event might explain the loss of control, it does not explain why the plane was flying at a low altitude. Because of the unknown flight circumstances just before the loss of control, it could not be determined whether the pilot's heart disease contributed to the accident.

Although toxicology test results for both occupants identified ethanol in some tissues, the levels varied widely and were negative on two tests for the pilot-certificated passenger. As a result, it is most likely that the identified ethanol was from sources other than ingestions.

Text from the NTSB. Open the NTSB docket for CEN17FA270 for the full record.