On September 12, 1990, a Cessna 177B (registration N35014) was involved in an aviation accident near Kokomo, IN. Investigators recorded the probable cause as: EXCEEDING THE DESIGN STRESS LIMITS OF THE AIRCRAFT WHILE RECOVERING FROM A LOSS OF CONTROL IN FLIGHT DUE TO SPATIAL DISORIENTATION. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
During a cross-country flight, a non-instrument-rated second pilot flying under the hood became disoriented while turning to avoid a thunderstorm, entering a spiralling descent into IMC. The instrument-rated pilot-in-command recovered but overstressed the aircraft, resulting in wing deformation and bent spar discovered later.
Flight Sequence
A cross-country flight was conducted with an instrument-rated pilot-in-command (PIC) and a second pilot who was not instrument rated. The second pilot was flying under the hood in visual meteorological conditions (VMC) at an altitude of 6,000 feet. The PIC instructed the second pilot to turn right to avoid a thunderstorm. During the turn, the second pilot became disoriented and entered a spiralling descent, which continued into instrument meteorological conditions (IMC).
Recovery and Aftermath
The PIC took control of the aircraft and executed a recovery maneuver. During the recovery, the aircraft was subjected to stresses that exceeded its design limits. The aircraft was subsequently flown to its intended destination and landed without incident. During a preflight inspection before the next flight, wing deformation and a bent spar were discovered.