General Wm J Fox Airfield Airport
Aircraft Accident/Incident Report

Lancaster, California 93534
Thursday, October 16, 2003 15:30 PDT

NTSB Narrative Summary Released at Completion of Accident

The airplane collided with power lines during an off-airport forced landing following a loss of engine power. While in cruise at 10,500 feet, the pilot heard a bang, and the engine lost power. He declared an emergency, and attempted to glide to a nearby airport; however, he was unable to make it to the runway. The airplane collided with power lines and fell to the ground about 4 miles west of the airport. The N1 and N2 shafting systems were bound up and would not move. The upper magnetic chip detector was free of metal, but it did contain coke. There was slight varnishing of the anode and cathode. The lower magnetic chip detector contained a substantial amount of metallic particles, subsequently identified as material from the No. 5 bearing. The particles did bridge the gap from anode to cathode. A detailed examination of the engine determined that three sections of the first stage turbine wheel separated. The stub shaft also fractured and separated, and a portion of the fractured tie bolt remained in the wheel. Metallurgical examination of the first and second stage turbine wheels found evidence of gamma prime solutioning and localized melting of the second stage turbine wheel airfoil tips, indicating temperature exposures above 2,100 degrees Farenheit, a temperature range outside the normal operating envelope of these wheels. This exposure to elevated temperatures resulted in rim separation due to thermal fatigue initiating at the rim followed by accelerated interdendritic creep crack growth. No evidence of an oil fire was associated with the first stage wheel separation. The composition, hardness, and microstructure of the first stage turbine wheel were as required by the engineering drawing. The No. 5 bearing exhibited heat distress, but the cause of this could not be conclusively determined. According to Rolls-Royce Allison, the internal evidence of excessive thermal damage to the first and second stage turbine wheels was consistent with prior examples of known hot starts.

NTSB Probable Cause Narrative

A loss of engine power due to thermal fatigue failure of the first stage turbine wheel resulting in release of a section of its rim. The thermal fatigue was due to the engine exceeding its temperature limits during one or more start cycles.

Event Information

Type of Event Accident
Event Date 10/16/2003
Event Day of the Week Thursday
Time of Event 1530
Event Time Zone Pacific Daylight Time
Event City Lancaster
Event State CALIFORNIA
Event Country --
Zipcode of the event site 93534
Event Date Year 2003
Event Date Month 10
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude 344712N
Event Location Longitude 1181725W
Event Location Airport General Wm J Fox Airfield
Event Location Nearest Airport ID WJF
Indicates whether the acc/inc occurred off or on an airport Off Airport/Airstrip
Distance from airport in statute miles 5.14
Degrees magnetic from airport 293
Airport Elevation 2348
Weather Briefing Completeness Full
Investigator's weather source Weather Observation Facility
Time of the weather observation 1456 Pacific Daylight Time
Direction of event from weather observation facility (degrees) 293
Weather Observation Facility ID WJF
Elevation of weather observation facility 2348
Distance of event from weather observation facility (units?) 5
Time Zone of the weather observation PDT
Lighting Conditions Day
Lowest Ceiling Height --
Lowest Non-Ceiling Height --
Sky/Lowest/Cloud Conditions Clear
Sky Condition for Lowest Ceiling None
Visibility Runway Visual Range (Feet) --
Visibility Runway Visual Value (Statute Miles) --
Visibility (Statute Miles) 10
Air Temperature at event time (in degrees celsius) 31
Dew Point at event time (in degress fahrenheit) 1
Wind Direction (degrees magnetic) --
Variable Wind Indicator Variable
Wind Speed (knots) 4
Wind Velocity Indicator --
Wind Gust Indicator Not Gusting
Wind Gust (knots) --
Altimeter Setting at event time (in. Hg) 30.09
Density Altitude (feet) 4641
Intensity of Precipitation --
METAR weather report --
Event Highest Injury None
On Ground, Fatal Injuries --
On Ground, Minor Injuries --
On Ground, Serious Injuries --
Injury Total Fatal --
Injury Total Minor --
Injury Total None 1
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 20581
NTSB Notification Source FAA
NTSB Notification Date Oct 16 2003 12:00AM
NTSB Notification Time 1545
Fiche Number and/or location -used to find docket information DMS
Date of most recent change to record Oct 31 2006 8:45AM
User who most recently changed record NTSB\JOHB
Basic weather conditions Visual Meteorological Cond
FAA District Office WP-VNY-FSDO

Aircraft Involved

Aircraft #1

Aircraft Registration Number N700TT
NTSB Number LAX04LA016
Missing Aircraft Indicator --
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed None
Flight plan Was Activated? No
Damage Substantial
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name Beech
Aircraft Model A36
Aircraft Series Identifier --
Aircraft Serial Number E-2361
Certified Max Gross Weight 3849
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 6
Number of Engines 1
Fixed gear or retractable gear Retractable
Aircraft, Type of Last Inspection Annual
Date of Last Inspection Feb 10 2003 12:00AM
Airframe hours since last inspection 5.2
Airframe Hours 1744.8
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name Lester Hill Trustee
Aircraft Owner Street Address --
Aircraft Owner City Capistrano Beach
Aircraft Owner State CA
Aircraft Owner Country USA
Aircraft Owner Zipcode 92624
Operator is an individual? No
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? --
Certified for Part 133 or 137 Operation --
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 No
Departure Airport Code FUL
Departure City Fullerton
Departure State CA
Departure Country USA
Departure Time 1435
Departure Time Zone PDT
Destination Same as Local Flt --
Destination Airport Code FAT
Destination City Fresno
Destination State CA
Destination Country USA
Specific Phase of Flight Cruise - normal
Report sent to ICAO? No
Evacuation occurred No
Date of most recent change to record Aug 26 2006 1:55PM
User who most recently changed record COOS
Since inspection or accident Time of Accident
Event Location Runway Number and Location NA
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --