San Diego Brown Field Airport
Aircraft Accident/Incident Report

San Diego, California 92173
Saturday, January 25, 1997 10:38 PST

NTSB Narrative Summary Released at Completion of Accident

According to pilots who were familiar with the experimental aircraft, the engine had a history of power loss events dating back several months prior to the accident flight. On the day of the accident, the CFI and the dual student/aircraft owner had completed two touch-and-go landings and were on crosswind leg when the engine abruptly quit. A crash and postcrash fire resulted from the ensuing forced landing. A postcrash investigation revealed that a check valve was present in the engine fuel system to provide fuel under pressure to the carburetor when the electric boost pump was operating. The check valve was disassembled and was found to have no internal components. This permitted the fuel to circulate back to the fuel pump inlet and interfered with fuel flow to the carburetor.

NTSB Probable Cause Narrative

Installation by the pilot/owner of an unairworthy check valve in the fuel system of the amateur built aircraft, which resulted in inadequate fuel flow to the engine and subsequent engine failure. A factor in the accident was the owner's operation of the aircraft with known deficiencies.

Event Information

Type of Event Accident
Event Date 1/25/1997
Event Day of the Week Saturday
Time of Event 1038
Event Time Zone Pacific Standard Time
Event City SAN DIEGO
Event State CALIFORNIA
Event Country --
Zipcode of the event site 92173
Event Date Year 1997
Event Date Month 1
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude
Event Location Longitude
Event Location Airport SAN DIEGO BROWN FIELD
Event Location Nearest Airport ID SDM
Indicates whether the acc/inc occurred off or on an airport Off Airport/Airstrip
Distance from airport in statute miles 1
Degrees magnetic from airport 30
Airport Elevation 524
Weather Briefing Completeness Not pertinent
Investigator's weather source Weather Observation Facility
Time of the weather observation 1051 Pacific Standard Time
Direction of event from weather observation facility (degrees) 120
Weather Observation Facility ID SDM
Elevation of weather observation facility 524
Distance of event from weather observation facility (units?) 1
Time Zone of the weather observation PST
Lighting Conditions Day
Lowest Ceiling Height 2500
Lowest Non-Ceiling Height 2000
Sky/Lowest/Cloud Conditions Scattered
Sky Condition for Lowest Ceiling Broken
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 8
Air Temperature at event time (in degrees celsius) --
Dew Point at event time (in degress fahrenheit) --
Wind Direction (degrees magnetic) 0
Variable Wind Indicator Unknown
Wind Speed (knots) 0
Wind Velocity Indicator Calm
Wind Gust Indicator Not Gusting
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 Fatal
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal 2
Injury Total Minor --
Injury Total None --
Injury Total Serious --
Injury Total All 2
Investigating Agency NTSB
NTSB Docket Number (internal use) 289
NTSB Notification Source --
NTSB Notification Date Jan 25 1997 12:00AM
NTSB Notification Time 1115
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Dec 8 2000 12:06PM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N40918
NTSB Number LAX97LA092
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed None
Flight plan Was Activated? --
Damage Destroyed
Aircraft Fire Ground
Aircraft Explosion None
Aircraft Manufacturer's Full Name Crane
Aircraft Model THORP T-18
Aircraft Series Identifier THORP T-18
Aircraft Serial Number 1
Certified Max Gross Weight --
Aircraft Category Airplane
Aircraft Registration Class U.S. Registered/U.S. Soil
Aircraft is a homebuilt? Yes
Flight Crew Seats --
Cabin Crew Seats --
Passenger Seats --
Total number of seats on the aircraft --
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection Annual
Date of Last Inspection Apr 3 1996 12:00AM
Airframe hours since last inspection --
Airframe Hours --
ELT Installed Unknown
ELT Activated Unknown
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name MARVIN A. CRANE
Aircraft Owner Street Address 10234 PARKDALE AVENUE
Aircraft Owner City SAN DIEGO
Aircraft Owner State CA
Aircraft Owner Country
Aircraft Owner Zipcode 92126
Operator is an individual? --
Operator Name
Operator Same as Owner? Yes
Operator Is Doing Business As --
Operator Address Same as Owner? Yes
Operator Street Address
Operator City
Operator State
Operator Country
Operator Zip code
Operator Code
Owner has at least one certificate None
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) Instructional
Second Pilot on Board Yes
Departure Point Same as Event Yes
Departure Airport Code SDM
Departure City
Departure State
Departure Country
Departure Time 1036
Departure Time Zone PST
Destination Same as Local Flt dest & departure same, accident can occur anywhere
Destination Airport Code
Destination City
Destination State
Destination Country
Specific Phase of Flight Takeoff
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Jan 2 2001 10:30AM
User who most recently changed record dbo
Since inspection or accident --
Event Location Runway Number and Location 26R
Runway Length 7999
Runway Width 200
Sight Seeing flight No
Air Medical Flight No
Medical Flight --