Pilot Debrief

NANCHANG CHINA CJ-6A near Peyton, CO — 2023-08-05

Final reportCEN23FA349
Sign in to save
Date
2023-08-05
Location
Peyton, CO, USA
Airport
KFLY
Aircraft
NANCHANG CHINA CJ-6A
Registration
N4184G
Category
Airplane
Highest injury
Fatal
Fatalities
1
Phase of flight
Approach

Probable cause

The pilot’s exceedance of the airplane’s critical angle of attack while intentionally maneuvering in a steep bank at low altitude, which resulted in an accelerated aerodynamic stall/spin and subsequent loss of airplane control.

NTSB narrative

The accident occurred during a prebriefed honor flight, performed at the conclusion of a retirement ceremony, that involved two airplanes of similar make and model flying low passes and maneuvers. Witnesses reported that the accident airplane, which was positioned behind the lead airplane, pitched up near vertical and rolled as it transitioned from the base to final leg of the airport traffic pattern. During the maneuver, the airplane entered a spiraling nose-down descent and impacted the ground. Both pilots had flown the airplanes uneventfully earlier that day. Although the lead pilot reported that they did not perform any aerobatic maneuvers during the accident flight, the accident airplane’s near-vertical climb and roll, as reported by the witnesses, was consistent with aerobatic flight. Examination of the accident site revealed that the airplane impacted the ground in a nose-low and right wing-low attitude and came to rest on a southeast heading about 158 ft from the initial impact area. The engine, propeller, and both wings were separated and located within the debris field. All major structural components of the airplane were located at the accident location. Examination revealed no anomalies with the engine or airframe that would have precluded normal operation. Damage signatures and witness accounts indicate that the engine was producing power at the time of the accident. Toxicology testing revealed that the pilot had an elevated HbA1c and urine glucose, with an HbA1c level indicative of uncontrolled diabetes with chronically elevated blood sugar. Symptoms of high blood sugar may include fatigue and blurred vision; in severe cases, high blood sugar can be associated with severe metabolic disturbances that can lead to altered consciousness. However, whether the pilot was experiencing significant impairing effects of his uncontrolled diabetes at the time of the accident could not be determined from the available medical evidence.

Analysis

Primary failure mode
Loss of control
First missed decision gate
Pilot could have avoided low pass maneuvers below 1500 ft to prevent loss of control.

NTSB coding

Evidence available

  • Photos
  • 17 docket documents
View NTSB final reportView NTSB docket

Docket documents17

Related mishaps