Amateur-built RV-6A N914ES accident near Knox, Indiana

Probable cause

The incapacitation of the pilot due to a cardiovascular event that prevented him from maintaining control of the airplane during the landing approach.

NTSB analysis

The amateur-built airplane was one of a group of five airplanes traveling to a fly-in. The group planned to land at an interim stop before continuing to the fly-in the following day. The accident airplane was the fourth to land. During the approach, the airplane impacted the ground about where a base-to-final approach turn would have been expected. GPS data showed that the airplane entered a descending left turn that reached a turn rate of about 900 degrees per minute and a descent rate of about 1,300 feet per minute before impact.

The pilot of the fifth airplane and his passenger commented that the final radio transmissions over the common traffic advisory frequency (CTAF) from the accident pilot seemed out of the ordinary and that he was fumbling for words. They said that this was not common for the accident pilot and that he was usually very precise in his radio transmissions. The accident pilot's wife reported that he had complained that he was not feeling well and had chest pain 2 days before the accident flight. Reportedly, he thought the chest pain was from a pulled muscle. The wife reported that the chest pain had resolved and that the pilot was feeling better by the time of the flight but that he had not seen a physician. Autopsy findings revealed that the pilot had left ventricular hypertrophy and coronary artery disease that put him at risk for an acute cardiac event; such an event would leave no evidence visible on autopsy. In addition, the pathologist's autopsy findings stated, "While no acute ischemic changes are found, the interstitial fibrosis is consistent with prior ischemia, and cardiac hypertrophy is associated with arrhythmias…Thus, it appears possible, given the information that decedent's radio transmissions on the CTAF prior to the accident indicated he was fumbling for words, that he suffered a cardiac arrhythmia prior to the accident." Examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation.

Text from the NTSB. Open the NTSB docket for CEN13FA446 for the full record.