FlarePath

What happened

NTSB summary, verbatim

The commercial pilot departed on a night instrument flight rules flight in actual instrument meteorological in-flight conditions. Less than 2 minutes after the airplane departed the airport, the controller observed the airplane in a right turn and instructed the pilot to report his altitude. The pilot responded he thought he was at 3,500 feet and he thought he had lost the gyros. The pilot said he was trying to level out, and when the controller informed the pilot he observed the airplane on radar making a 360-degree right turn , the pilot said "roger." Three minutes and 23 seconds after departure the pilot said "yeah, I'm having some trouble right now" and there were no further radio communications from the flight. The on scene investigation disclosed that both wings and the tail section had separated from the airframe. All fractures of the wing and wing skin were typical of ductile overload with no evidence of preexisting failures such as fatigue or stress-corrosion. The deformation of the wings indicated an upward failure due to positive loading. No anomalies were noted with the gyro instruments, engine assembly or accessories

Photographs

8the aircraft, and what the investigators found

Wreckage and site documentation · 8 photographs from the docket

Photographs are NTSB docket attachments — works of the US government, in the public domain. Captions are the Board’s own.

Probable cause

the Board's determination

The pilot's loss of control due to spatial disorientation and the pilot exceeding the design/stress limits of the aircraft. Factors contributing to the accident were the pilot's reported gyro problem, the dark night conditions , and prevailing instrument meteorological conditions.

Occurrence sequence

4 stepsNTSB coding · CICTT taxonomy

1 · Initial climb
Flight instrument malf/fail
2 · Initial climb
Loss of control in flight
defining event
3 · Initial climb
Attempted remediation/recovery
4 · Initial climb
Aircraft structural failure

Findings

6 causal · 0 contributing

CAUSE
Aircraft › Aircraft systems › Vacuum system › Vacuum indicating system — Malfunction
CAUSE
Personnel issues › Psychological › Perception/orientation/illusion › Spatial disorientation — Pilot
CAUSE
Aircraft › Aircraft oper/perf/capability › Performance/control parameters — Not attained/maintained
CAUSE
Aircraft › Aircraft structures › (general) — Capability exceeded
CAUSE
Environmental issues › Conditions/weather/phenomena › Light condition › Dark — Not specified
CAUSE
Environmental issues › Conditions/weather/phenomena › Ceiling/visibility/precip › Below VFR minima — Not specified

NTSB analysis

from the final report

The commercial pilot departed on a night instrument flight rules flight in actual instrument meteorological in-flight conditions. Less than 2 minutes after the airplane departed the airport, the controller observed the airplane in a right turn and instructed the pilot to report his altitude. The pilot responded he thought he was at 3,500 feet and he thought he had lost the gyros. The pilot said he was trying to level out, and when the controller informed the pilot he observed the airplane on radar making a 360-degree right turn , the pilot said "roger." Three minutes and 23 seconds after departure the pilot said "yeah, I'm having some trouble right now" and there were no further radio communications from the flight. The on scene investigation disclosed that both wings and the tail section had separated from the airframe. All fractures of the wing and wing skin were typical of ductile overload with no evidence of preexisting failures such as fatigue or stress-corrosion. The deformation of the wings indicated an upward failure due to positive loading. No anomalies were noted with the gyro instruments, engine assembly or accessories

AERO COMMANDER 500BCentral Air Southwest