Casualties unknown

Pilot Collides with Terrain Near Carmel Valley Airport (N80274)

Carmel Valley, CA, US

On November 10, 1991, a Cessna 172M (registration N80274) operated by William T. Cleverdon, Iii was involved in an aviation accident near Carmel Valley, CA. Investigators recorded the probable cause as: THE PILOT'S FAILURE TO MAINTAIN A SAFE ALTITUDE ABOVE THE GROUND DURING AN INTENTIONAL LOW ALTITUDE FLIGHT IN MOUNTAINOUS TERRAIN. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 2026-07-04Data APIEditorial standards

A pilot flying to Carmel Valley Airport on a clear day descended low, flew past the airport, then turned toward a box canyon and collided with rising terrain. No mechanical issues found.

Accident Details

On a clear day with 15 miles visibility, a pilot flew to Carmel Valley Airport. Witnesses observed the aircraft descend to between 200 and 300 feet above ground level (650 and 750 feet mean sea level). The aircraft then flew past the airport; its ground track was initially parallel to the runway but approximately 570 feet south of Runway 29. Witnesses reported the aircraft was flying slowly.

After traveling about eight-tenths of a mile past the airport, the aircraft turned right and flew approximately six-tenths of a mile, heading toward the rising terrain of a box canyon. Just before impact, the aircraft began a left turn and collided with terrain that had a 40-degree upslope at an elevation of about 850 feet mean sea level.

Pilot and Aircraft Background

The pilot had flown the same aircraft to the same airport seven weeks earlier. A pilot examiner reported that the airport was clearly visible from the air and was not difficult to locate, especially after having been there once.

Mechanical Examination

An examination of the airframe and engine revealed no preimpact mechanical malfunction.

Frequently asked questions

What happened in the 10 Nov 1991 Cessna 172M accident near Carmel Valley, CA?

A pilot flying to Carmel Valley Airport on a clear day descended low, flew past the airport, then turned toward a box canyon and collided with rising terrain. No mechanical issues found.

What aircraft was involved and where did it happen?

The accident on 10 Nov 1991 involved a Cessna 172M, registration N80274, operated by William T. Cleverdon, Iii, at Carmel Valley, CA.

What was the probable cause of the accident?

THE PILOT'S FAILURE TO MAINTAIN A SAFE ALTITUDE ABOVE THE GROUND DURING AN INTENTIONAL LOW ALTITUDE FLIGHT IN MOUNTAINOUS TERRAIN. CONTRIBUTING FACTORS RELATED TO THE PILOT BECOMING DISTRACTED WHILE FLYING OVER THE GROUND AND TO HIS FAILURE TO INITIATE A CLIMB OR TAKE OTHER CORRECTIVE ACTION BY ALTERING HIS COURSE IN…

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001212X18459. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.