Thermal Airport
Aircraft Accident/Incident Report

Thermal, California 92274
Wednesday, March 18, 1998 14:45 PST

NTSB Narrative Summary Released at Completion of Accident

The aircraft lost power while towing a glider and made an emergency landing. Examination of the engine revealed that the crankcase upper surface near the number three cylinder was cracked and displaced outward. The oil pump drive coupling at the crankshaft gear displayed signatures consistent with heat distress. The oil pump drive at the oil pump would not rotate. The oil pump housing and mounting pad were free of any rotational scoring and did not display evidence of oil starvation or metal contamination. The crankshaft gear was a Lycoming part number 13S19648 and is the part number for the Lycoming IO-540 series engines. The engine in the accident aircraft is a Lycoming O-540-B2B5 and the crankshaft gear part number for this engine is 13S19647.

NTSB Probable Cause Narrative

The failure of the oil pump drive shaft due to the installation of an incorrect oil pump crankshaft gear by maintenance personnel at the last overhaul.

Event Information

Type of Event Accident
Event Date 3/18/1998
Event Day of the Week Wednesday
Time of Event 1445
Event Time Zone Pacific Standard Time
Event City THERMAL
Event State CALIFORNIA
Event Country --
Zipcode of the event site 92274
Event Date Year 1998
Event Date Month 3
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude
Event Location Longitude
Event Location Airport THERMAL
Event Location Nearest Airport ID TRM
Indicates whether the acc/inc occurred off or on an airport Off Airport/Airstrip
Distance from airport in statute miles --
Degrees magnetic from airport --
Airport Elevation -117
Weather Briefing Completeness Not pertinent
Investigator's weather source Weather Observation Facility
Time of the weather observation 2150 Pacific Standard Time
Direction of event from weather observation facility (degrees) 0
Weather Observation Facility ID KTR
Elevation of weather observation facility 0
Distance of event from weather observation facility (units?) 0
Time Zone of the weather observation PST
Lighting Conditions Day
Lowest Ceiling Height 0
Lowest Non-Ceiling Height 0
Sky/Lowest/Cloud Conditions Scattered
Sky Condition for Lowest Ceiling Unknown
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 25
Air Temperature at event time (in degrees celsius) 27
Dew Point at event time (in degress fahrenheit) 3
Wind Direction (degrees magnetic) 190
Variable Wind Indicator Unknown
Wind Speed (knots) 9
Wind Velocity Indicator Unknown
Wind Gust Indicator Not Gusting
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) 29
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) 427
NTSB Notification Source --
NTSB Notification Date Mar 18 1998 12:00AM
NTSB Notification Time 1515
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Dec 11 2000 10:56AM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N7211V
NTSB Number LAX98LA131
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 None
Aircraft Explosion None
Aircraft Manufacturer's Full Name Callair
Aircraft Model A-9
Aircraft Series Identifier A-9
Aircraft Serial Number 1248
Certified Max Gross Weight --
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 --
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection Annual
Date of Last Inspection Dec 26 1997 12:00AM
Airframe hours since last inspection 100
Airframe Hours 6507
ELT Installed No
ELT Activated Unknown
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name SAILPLANE ENTERPRISES INTL
Aircraft Owner Street Address 36038 WHITTIER AVENUE
Aircraft Owner City HEMET
Aircraft Owner State CA
Aircraft Owner Country
Aircraft Owner Zipcode 92543
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) Personal
Second Pilot on Board No
Departure Point Same as Event Yes
Departure Airport Code TRM
Departure City
Departure State
Departure Country
Departure Time 1445
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 Climb
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Jan 2 2001 10:34AM
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 --