Cessna 150K N6312G accident near Gilford, New Hampshire

Probable cause

The pilot’s loss of control during visual flight rules flight in night instrument meteorological conditions due to spatial disorientation. Contributing to the accident was the pilot’s motivation to depart on the flight despite being made aware that conditions might be unsafe and his continuation of the flight as weather conditions deteriorated.

NTSB analysis

The pilot was completing a cross-country flight at night and had arrived in the area of the destination airport. After entering an extended downwind leg of the traffic pattern, he was flying over a lake when the accident occurred. The airplane entered a left base-to-final turn that developed into a steep, spiral dive to the right, and continued until the airplane impacted the lake. The airplane lacked an autopilot; therefore, it was being manually flown by the pilot. No preimpact malfunctions of the airplane were identified during a postaccident examination of the recovered wreckage.

The pilot was not instrument-rated and had no recent experience flying at night. Witnesses indicated visibility in the area was reduced by wildfire smoke. Surveillance video confirmed that the sky was obscured and that the airplane was flying through low clouds immediately before the loss of control occurred. Few ground lights or other visual references were available in the vicinity of the lake that could have helped the pilot maintain orientation or aid in recovery after he lost control of the airplane. Loss of outside visual references during a visual flight rules (VFR) flight creates a high risk of spatial disorientation and loss of control for pilots who are not instrument-rated and current/proficient. Several risk factors for spatial disorientation were present in this case: reduced visibility, manual control, and maneuvering flight. Therefore, the pilot likely experienced spatial disorientation followed by a loss of control in flight.

The pilot was advised by a flight instructor before departing on the accident flight that meteorological information indicated visibility might be diminished by the time he arrived at the destination airport, but he decided to depart anyway. According to the instructor, who was a friend of the pilot, the pilot had experienced multiple delays returning the accident airplane to his home and had plans with a friend that evening. Thus, the pilot appears to have disregarded information that the flight might have been unsafe to operate under VFR, and he likely did not divert because he was motivated to avoid further delays and attend to a social obligation.

Text from the NTSB. Open the NTSB docket for ERA23FA384 for the full record.