Flight Conduct
During the first 15 minutes of the flight, the pilot of a complex, high-performance jet airplane exhibited difficulty maintaining the headings and altitudes assigned by air traffic controllers. Throughout the flight, the pilot responded intermittently to controller instructions. After reaching an altitude of 27,000 feet, the airplane began to deviate about 30 degrees right of course while continuing to climb. The controller alerted the pilot, who did not respond, and the airplane continued to climb. Two minutes later, the airplane entered a tight, spiraling descent that lasted 8 minutes until it impacted the ground at high speed in a right-wing-low attitude.
Pilot Background
The 72-year-old private pilot had extensive flight experience in multiple types of aircraft, including jets, but did not hold a type rating in the accident airplane. The accident flight was likely the first time he had flown it solo. He had received training in the airplane about two months before the accident but was not issued a type rating and left before the training was complete. During training, he struggled significantly in high-workload environments and had difficulty operating the airplane’s avionics suite, which had recently been installed. He revealed to a fellow pilot that he preferred to “hand fly” the airplane rather than use the autopilot.
Examination
The airplane was highly fragmented on impact; however, examination did not reveal any evidence of structural failure, in-flight fire, bird strike, or cabin depressurization event. Both engines appeared to be producing power at impact. The heading and flight path before the spiraling descent were consistent with the pilot not using the autopilot. Review of the flight path during the spiraling descent indicated that speed variations closely matched the airplane’s open-loop phugoid response as documented during manufacturer flight tests; therefore, it is likely that the pilot was not manipulating the controls during that time.
Probable Cause
The official probable cause of the accident was a loss of airplane control due to pilot incapacitation for reasons that could not be determined.