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NTSB Report
May 18, 1991 · Cessna 152 · N6507H
Richmond, CA
Overview
Report Status
Probable Cause
Event Type
Accident
Date
May 18, 1991
Injury Outcomes
No injuries (2 uninjured)
Location
Richmond, CA
Aircraft
Cessna 152
Tail Number
N6507H
Operator
Univ of Calif Flying Club
Injuries
None
Aircraft Damage
Substantial
NTSB Number
LAX91LA218
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'.
NTSB 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.
Full Narrative
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'.
Flight
Event TypeAccident
Event Time11:15 PDT
Nearest Airport0nm N
Runway0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftCessna 152
Tail NumberN6507H
Aircraft CategoryAir
DamageSubstantial
OperatorUniv of Calif Flying Club
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · O-235-12C · Reciprocating · 110
Seats2
People & Injuries
Injury SummaryNo injuries (2 uninjured)
Fatal0
Serious0
Minor0
Uninjured2
Total2
Crew 1Age 22 · First Class
Conditions
ConditionsVMC
LightDaylight
WindCalm
Visibility15 sm
CeilingNone
Temperature / Dew Point0 C / 0 C
Altimeter0
Weather SourcePILO