Aircraft Accident/Incident Report

Pearblossom, California 93563
Saturday, August 13, 1994 13:31 PDT

NTSB Narrative Summary Released at Completion of Accident

While in level flight, the airplane's right wing separated and, during the separation sequence, wing fuel ignited. Subsequent laboratory examination of right-side, center-wing fragments revealed two fatigue cracks that propagated to overstress fractures. One of the cracks was within the underside wing skin below a doubler, and the other was within the doubler itself. The total size and origin of the fatigue regions could not be determined due to damage to fracture surfaces and a lack of available material. The airplane was delivered new to the U.S. Air Force in December 1957 and was retired from military service in 1986. In May 1990, the FAA issued a restricted-category special airworthiness certificate authorizing the airplane to dispense aerial fire retardant. At the time of the accident, the airplane had a total of 20,289 flight hours, 19,547 of which were acquired during its military service. The inspection and maintenance programs used by the operator, which were based on military standards, included general visual inspections for cracks but did not include enhanced or focused inspections of highly stressed areas, such as the wing sections, where the fatigue cracks that led to those accidents were located. The operator did not possess the engineering expertise necessary to conduct studies and engineering analysis to define the stresses associated with the firefighting operating environment and to predict the effects of those stresses on the operational life of the airplanes.

NTSB Probable Cause Narrative

the inflight failure of the right wing due to fatigue cracking in the underside right wing skin and overlying doubler. A factor contributing to the accident was inadequate maintenance procedures to detect fatigue cracking.

Event Information

Type of Event Accident
Event Date 8/13/1994
Event Day of the Week Saturday
Time of Event 1331
Event Time Zone Pacific Daylight Time
Event City PEARBLOSSOM
Event State CALIFORNIA
Event Country --
Zipcode of the event site 93563
Event Date Year 1994
Event Date Month 8
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude
Event Location Longitude
Event Location Airport
Event Location Nearest Airport ID
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 --
Weather Briefing Completeness Unknown
Investigator's weather source Weather Observation Facility
Time of the weather observation 1259 Pacific Daylight Time
Direction of event from weather observation facility (degrees) 315
Weather Observation Facility ID PMD
Elevation of weather observation facility 2543
Distance of event from weather observation facility (units?) 16
Time Zone of the weather observation PDT
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) 50
Air Temperature at event time (in degrees celsius) 39
Dew Point at event time (in degress fahrenheit) 10
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 3
Injury Total Minor --
Injury Total None --
Injury Total Serious --
Injury Total All 3
Investigating Agency NTSB
NTSB Docket Number (internal use) 2073
NTSB Notification Source --
NTSB Notification Date Aug 13 1994 12:00AM
NTSB Notification Time 1355
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Dec 6 2000 12:00PM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N135FF
NTSB Number LAX94FA323
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 137: Agricultural
Type of Flight Plan filed Company VFR
Flight plan Was Activated? --
Damage Destroyed
Aircraft Fire In-flight
Aircraft Explosion In-flight
Aircraft Manufacturer's Full Name LOCKHEED
Aircraft Model C-130A
Aircraft Series Identifier C-130A
Aircraft Serial Number 56-540
Certified Max Gross Weight 120000
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 3
Number of Engines 4
Fixed gear or retractable gear Retractable
Aircraft, Type of Last Inspection AAIP
Date of Last Inspection Aug 7 1994 12:00AM
Airframe hours since last inspection 10
Airframe Hours 20300
ELT Installed Yes
ELT Activated Unknown
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name AERO FIREFIGHTING SVC CO INC
Aircraft Owner Street Address 631 S. MANCHESTER
Aircraft Owner City ANAHEIM
Aircraft Owner State CA
Aircraft Owner Country
Aircraft Owner Zipcode 92802
Operator is an individual? --
Operator Name JAMES A. VENABLE
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address P.O. BOX 3780
Operator City HEMET
Operator State CA
Operator Country
Operator Zip code 92546
Operator Code RPEG
Owner has at least one certificate Yes - certificate holder
Other Operator of large aircraft? No
Certified for Part 133 or 137 Operation Agriculture
Operator Certificate Number --
Indicates whether an air carrier operation was scheduled or not Unknown
Indicates Domestic or International Flight Unknown
Operator carrying Pax/Cargo/Mail Unknown
Type of Flying (Per_Bus / Primary) Public Use
Second Pilot on Board Yes
Departure Point Same as Event No
Departure Airport Code HMT
Departure City HEMET
Departure State CA
Departure Country
Departure Time 1312
Departure Time Zone PDT
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 Cruise
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 0
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --