Hayward Airport
Aircraft Accident/Incident Report

Hayward, California 94541
Thursday, July 2, 1992 17:45 PDT

NTSB Narrative Summary Released at Completion of Accident

THE PILOT REPORTED THAT HE OVERPRIMED THE RIGHT ENGINE WHEN HE ATTEMPTED TO START IT. DURING THE START OPERATION, AN ACCUMULATION OF FUEL VAPOR LOCATED OUTBOARD OF THE RIGHT ENGINE EXPLODED AND RIPPED OPEN A YARD LONG PORTION OF THE RIGHT WING'S UPPER SKIN PANELS. EVIDENCE WAS OBSERVED OF AN UNCORRECTED PREEXISTING FUEL LEAK IN THE VICINITY OF THE RIGHT ENGINE'S AUXILIARY FUEL PUMP. THE PILOT REPORTED THAT HE WAS AN A & P MECHANIC, AND HE OWNED, OPERATED AND MAINTAINED THE AIRPLANE.

NTSB Probable Cause Narrative

THE EXPLOSION OF FUEL VAPORS IN THE RIGHT WING DUE TO THE PILOT'S OVERPRIMING OF THE RIGHT ENGINE DURING A START ATTEMPT AND AN UNCORRECTED PREEXISTING FUEL SYSTEM LEAK. A FACTOR IN THE ACCIDENT WAS INADEQUATE MAINTENANCE PERFORMED ON THE AIRCRAFT.

Event Information

Type of Event Accident
Event Date 7/2/1992
Event Day of the Week Thursday
Time of Event 1745
Event Time Zone Pacific Daylight Time
Event City HAYWARD
Event State CALIFORNIA
Event Country --
Zipcode of the event site 94541
Event Date Year 1992
Event Date Month 7
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude
Event Location Longitude
Event Location Airport HAYWARD
Event Location Nearest Airport ID HWD
Indicates whether the acc/inc occurred off or on an airport On Airport
Distance from airport in statute miles 0
Degrees magnetic from airport 0
Airport Elevation --
Weather Briefing Completeness Unknown
Investigator's weather source Pilot
Time of the weather observation 0
Direction of event from weather observation facility (degrees) 0
Weather Observation Facility ID
Elevation of weather observation facility 0
Distance of event from weather observation facility (units?) 0
Time Zone of the weather observation
Lighting Conditions Day
Lowest Ceiling Height 0
Lowest Non-Ceiling Height 0
Sky/Lowest/Cloud Conditions Clear
Sky Condition for Lowest Ceiling None
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 0
Air Temperature at event time (in degrees celsius) 21
Dew Point at event time (in degress fahrenheit) --
Wind Direction (degrees magnetic) 270
Variable Wind Indicator Unknown
Wind Speed (knots) 5
Wind Velocity Indicator Unknown
Wind Gust Indicator Unknown
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) 30
Density Altitude (feet) --
Intensity of Precipitation Unknown
METAR weather report --
Event Highest Injury None
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal --
Injury Total Minor --
Injury Total None 1
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 2994
NTSB Notification Source --
NTSB Notification Date Jul 3 1992 12:00AM
NTSB Notification Time 1000
Fiche Number and/or location -used to find docket information 47840
Date of most recent change to record Dec 11 2000 3:05PM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N11BU
NTSB Number LAX92LA276
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed None
Flight plan Was Activated? --
Damage Substantial
Aircraft Fire Ground
Aircraft Explosion Ground
Aircraft Manufacturer's Full Name CESSNA
Aircraft Model 421B
Aircraft Series Identifier 421B
Aircraft Serial Number 421B0912
Certified Max Gross Weight 7450
Aircraft Category Airplane
Aircraft Registration Class U.S. Registered/U.S. Soil
Aircraft is a homebuilt? No
Flight Crew Seats --
Cabin Crew Seats --
Passenger Seats --
Total number of seats on the aircraft 8
Number of Engines 2
Fixed gear or retractable gear Retractable
Aircraft, Type of Last Inspection 100 Hour
Date of Last Inspection Apr 8 1992 12:00AM
Airframe hours since last inspection 90
Airframe Hours --
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name PETER J. DANTO
Aircraft Owner Street Address 236 SENIC AVENUE
Aircraft Owner City PIEDMONT
Aircraft Owner State CA
Aircraft Owner Country
Aircraft Owner Zipcode 94611
Operator is an individual? --
Operator Name PROFESSIONAL PILOT ASSOCIATES
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? Yes
Operator Street Address 236 SENIC AVENUE
Operator City PIEDMONT
Operator State CA
Operator Country
Operator Zip code 94611
Operator Code KIMA
Owner has at least one certificate Yes - certificate holder
Other Operator of large aircraft? No
Certified for Part 133 or 137 Operation Unknown
Operator Certificate Number --
Indicates whether an air carrier operation was scheduled or not --
Indicates Domestic or International Flight --
Operator carrying Pax/Cargo/Mail --
Type of Flying (Per_Bus / Primary) Positioning
Second Pilot on Board No
Departure Point Same as Event Yes
Departure Airport Code HWD
Departure City
Departure State
Departure Country
Departure Time 0
Departure Time Zone
Destination Same as Local Flt --
Destination Airport Code OAK
Destination City OAKLAND
Destination State CA
Destination Country
Specific Phase of Flight Standing
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Jan 2 2001 10:35AM
User who most recently changed record dbo
Since inspection or accident --
Event Location Runway Number and Location 0
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --