Piper PA-32R-301 N408DM accident near Kirksville, Missouri

Probable cause

A loss of control due to spatial disorientation. Contributing to the accident were the private pilot's impairment due to a sedating antihistamine and both pilots' fatigue.

NTSB analysis

The flight instructor accompanied the private pilot on a business flight to provide instrument flight instruction. Dark night instrument meteorological conditions prevailed with a 15-knot headwind that was gusting to 20 knots. The pilots were cleared for an instrument approach and instructed to change to the local advisory frequency. Recorded radar data indicated that the airplane was tracking the inbound course to the airport. One of the pilots contacted the airport on the local advisory frequency and gave two position reports; the last one reported the airplane was 5 miles from the airport. There was no other communication with the pilots. It could not be determined which pilot was flying the airplane when the accident occurred.

The wreckage was located about 3.5 miles north of the airport, and the initial tree impact was about 0.4 mile east of the last radar contact. The location of the accident site was consistent with the airplane turning left away from the inbound course and descending rapidly after the last radar contact. Given the dark night instrument meteorological conditions, the most likely explanation for the turn and rapid descent is that the flying pilot experienced spatial disorientation and lost control of the airplane. Examination of the accident site indicated that the airplane was in a nose-up attitude when it contacted the trees on the up sloping terrain, and it continued to climb, clearing the crest of the hill and continuing down the other side, before it came to rest. The wreckage path was consistent with a possible attempt to recover from the descent just before impacting the trees, but by then there was insufficient altitude to avoid the accident. Examination of the airplane and engine found no evidence of preimpact mechanical malfunctions or failures that would have precluded normal operation.

A commuter airline pilot who landed at the airport 15 minutes before the accident stated that the weather conditions were such that the lights from the radio antenna towers along the approach course illuminated the clouds around him with a white flashing light similar to airplane anti-collision lights or runway end identifier lights. If similar conditions were present during the accident airplane's approach, this phenomenon could have distracted the pilots. However, there is insufficient information to determine either the presence of this phenomenon during the accident airplane's approach or its role in this accident.

The pilots began their first flight of the day about 0804, and the accident occurred on their third flight of the day at 1912. Assuming the pilots woke up about 2 hours before they began the first flight, they had been awake about 13 hours when the accident occurred. The combined flights totaled about 5 hours 46 minutes of flight time. The cumulative flight time in conjunction with the extended time since awakening most likely resulted in the pilots experiencing some level of fatigue at the time of the accident.

Although the instructor's autopsy revealed that he had severe coronary artery disease, it could not be determined whether this contributed to the accident. The private pilot's toxicology results were positive for diphenhydramine, a sedating antihistamine, and impairment from this over-the-counter medication likely contributed to the accident whether he was actively flying or observing the instructor fly the approach at the time of the loss of control.

Text from the NTSB. Open the NTSB docket for CEN14FA042 for the full record.