# NTSB LAX91LA218: Cessna 152, N6507H, Richmond, CA, May 18, 1991

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: May 18, 1991, 11:15 local (18:15 UTC)
- Place: Richmond, CA
- Coordinates: 37.919616, -122.340469 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=37.9196&lon=-122.3405&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report May 27, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 27211
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX91LA218
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/27211/pdf
- Page: https://openairdocs.org/ntsb/LAX91LA218

## Probable cause

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.

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Loss of engine power(total) - nonmechanical, cruise
  - weather condition - carburetor icing conditions (cause)
  - carburetor heat - not used, pilot in command(cfi) (cause)
  - supervision - inadequate, pilot in command(cfi) (contributing factor)
- Forced landing, descent - emergency
  - terrain condition - ravine
- In flight collision with object, descent - emergency
  - object - bridge/overpass

## Analysis

THE LOCAL AREA DUAL INSTRUCTIONAL FLIGHT WAS ENROUTE TO THE PRACTICE AREA AT AN ALTITUDE OF 1,300 FEET WHEN THE ENGINE SUDDENLY LOST POWER. THE INSTRUCTOR'S ATTEMPTS TO REMEDY THE LOSS OF POWER WERE UNSUCCESSFUL AND THE AIRCRAFT COLLIDED WITH A BRIDGE STRUCTURE AND AN AUTOMOBILE DURING AN ATTEMPTED FORCED LANDING ON A FREEWAY. THE AIRCRAFT WAS EXAMINED BY AN FAA AIRWORTHINESS INSPECTOR. IN HIS REPORT OF THE EXAMINATION, THE INSPECTOR NOTED THAT NO MECHANICAL MALFUNCTIONS OR FAILURES WERE IDENTIFIED. THE OAKLAND, CALIFORNIA, AVIATION WEATHER OBSERVATION TAKEN AT 0945 HOURS REPORTED A TEMPERATURE OF 55 DEGREES AND A DEW POINT OF 41 DEGREES. REVIEW OF A CARBURETOR ICING PROBABILITY CHART REVEALED THAT THE TEMPERATURE AND DEW POINT FALLS WITHIN AN AREA DEFINED AS 'SERIOUS ICING - CRUISE OR CLIMB POWER'.

## Aircraft

- Registration: [N6507H](https://openairdocs.org/deregistered/N6507H-1993-11-29), registration cancelled 1993-11-29, S/N 15284174 (OpenAirDocs)
- Reported make and model: CESSNA 152
- Registry model: [Cessna 152](https://openairdocs.org/model/cessna-152) (registry code 2071835) (OpenAirDocs)
- Category: Airplane
- Serial number: 15284174
- Engines: LYCOMING O-235-12C 110 horsepower reciprocating
- Damage: Substantial damage
- Flight: Instructional, Part 91
- Operator: Univ Of Calif Flying Club
- Registered owner: Univ Of Calif Flying Club
- Last inspection: Unknown, January 2, 2000
- Departed: OAK, OAKLAND, CA

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 22; commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; flight hours: 2,000 total, 1,000 in this make and model, 1,800 as pilot in command, 200 in the last 90 days, 50 in the last 30 days, 3 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Visibility: 15 statute miles

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Accident 19910518016489A](https://openairdocs.org/incident/19910518016489A), May 18, 1991: Cessna 152, Richmond, CA, Substantial damage. Engine quit on training flight,struck a freeway divider on forced landing. No defects. Carb ice conditions existed.

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

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