Casualties unknown

Instructional Flight Loses Engine Power, Collides with Bridge and Car During Freeway Landing (N6507H)

Richmond, CA, US

On May 18, 1991, a Cessna 152 (registration N6507H) operated by Univ OF Calif Flying Club was involved in an aviation accident near Richmond, CA. Investigators recorded the probable cause as: LOSS OF ENGINE POWER DUE TO CARBURETOR ICE. A FACTOR IN THE ACCIDENT WAS THE FAILURE OF THE INSTRUCTOR TO PROPERLY SUPERVISE THE CONDUCT OF THE FLIGHT. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive; 8 related events involving the same aircraft type or operator are linked below.

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

A dual instructional flight experienced a sudden engine power loss at 1,300 feet. The instructor's attempts to restore power failed, leading to a forced landing on a freeway where the aircraft struck a bridge structure and an automobile.

Incident Overview

A local area dual instructional flight was en route to the practice area at an altitude of 1,300 feet when the engine suddenly lost power. The instructor attempted to remedy the power loss but was unsuccessful. During the subsequent forced landing attempt on a freeway, the aircraft collided with a bridge structure and an automobile.

Examination

The aircraft was examined by an FAA airworthiness inspector. According to the inspector's report, no mechanical malfunctions or failures were identified.

Weather Conditions

The Oakland, California, aviation weather observation taken at 0945 hours reported a temperature of 55 degrees Fahrenheit and a dew point of 41 degrees Fahrenheit. Review of a carburetor icing probability chart revealed that the temperature and dew point combination falls within an area defined as “serious icing – cruise or climb power.”

Additional Details

The source does not specify the aircraft type, registration, engine count, date, operator, number of occupants, injuries, or damage items. No analysis or conclusions beyond the stated facts are provided.

All Cessna 152 accidents →

Frequently asked questions

What happened in the 18 May 1991 Cessna 152 accident near Richmond, CA?

A dual instructional flight experienced a sudden engine power loss at 1,300 feet. The instructor's attempts to restore power failed, leading to a forced landing on a freeway where the aircraft struck a bridge structure and an automobile.

What aircraft was involved and where did it happen?

The accident on 18 May 1991 involved a Cessna 152, registration N6507H, operated by Univ OF Calif Flying Club, at Richmond, CA.

What was the probable cause of the accident?

LOSS OF ENGINE POWER DUE TO CARBURETOR ICE. A FACTOR IN THE ACCIDENT WAS THE FAILURE OF THE INSTRUCTOR TO PROPERLY SUPERVISE THE CONDUCT OF THE FLIGHT.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001212X17048. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.