Chino Airport
Aircraft Accident/Incident Report

Pomona, California 91768
Wednesday, August 17, 2005 19:50 PDT

NTSB Narrative Summary Released at Completion of Accident

While on approach for the destination airport, the pilot reported engine problems, and attempted to land in a field short of the airport. During the forced landing, the left wing contacted the ground, and the airplane tumbled through an impact sequence. During the postaccident engine examination, investigators noted debris and corrosion inside the carburetor and the main jet passage. The airframe and engine inspection revealed no further mechanical anomalies that would have precluded normal operation. A Safety Board metallurgist examined the carburetor and debris/particles. The examination identified that the debris/particles were most likely a combination of lead and soil that had built up over time. The corrosion indicated prolonged exposure to water. The particles probably caused a restricted flow of air-fuel mixture in the main jet that eventually resulted in a reduction or loss of engine power once the particulate contamination had built up to a significant amount. There were no entries in either the airframe or engine logbook indicating that the carburetor had ever been overhauled in its 46-year history. The carburetor manufacturer issued a service bulletin regarding the overhaul of the accident airplanes' carburetor. The recommended time for the overhaul was either at the engine manufacturer's time between overhaul, or every 10 years the carburetor was in service, whichever came first. While service bulletins are not mandatory, had the carburetor been inspected at the manufacturer's recommended intervals, the corrosion and debris may have been identified and source of the fuel system contamination corrected. Investigators noted that the airplane had not been equipped with a shoulder harness restraint system. The fatal injuries for the pilot and front seat passenger were caused by head and upper torso trauma associated with the upper body not being restrained during the impact sequence. The airplane manufacturer had issued Service Bulletin No. 980, Shoulder Harness Installation, in 1995, for the accident make and model airplane. The pilot/owner had purchased the shoulder harness restraint system kit for his airplane, but had not installed them. The still packaged shoulder harnesses were found in the debris field by the investigation team.

NTSB Probable Cause Narrative

A loss of engine power during the landing approach due to fuel starvation caused by debris and corrosion in the carburetor assembly. A factor contributing to the accident was the failure of the owner to comply with the manufacturer's service bulletin regarding overhaul of the carburetor.

Event Information

Type of Event Accident
Event Date 8/17/2005
Event Day of the Week Wednesday
Time of Event 1950
Event Time Zone Pacific Daylight Time
Event City Pomona
Event State CALIFORNIA
Event Country --
Zipcode of the event site 91768
Event Date Year 2005
Event Date Month 8
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude 340201N
Event Location Longitude 1174913W
Event Location Airport CHINO
Event Location Nearest Airport ID CNO
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 --
Investigator's weather source Weather Observation Facility
Time of the weather observation 1953 Pacific Standard Time
Direction of event from weather observation facility (degrees) 310
Weather Observation Facility ID CNO
Elevation of weather observation facility 652
Distance of event from weather observation facility (units?) 7
Time Zone of the weather observation PST
Lighting Conditions Dusk
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) 7
Air Temperature at event time (in degrees celsius) 18
Dew Point at event time (in degress fahrenheit) 14
Wind Direction (degrees magnetic) --
Variable Wind Indicator --
Wind Speed (knots) --
Wind Velocity Indicator Calm
Wind Gust Indicator Not Gusting
Wind Gust (knots) --
Altimeter Setting at event time (in. Hg) 29.91
Density Altitude (feet) --
Intensity of Precipitation --
METAR weather report --
Event Highest Injury Fatal
On Ground, Fatal Injuries --
On Ground, Minor Injuries --
On Ground, Serious Injuries --
Injury Total Fatal 2
Injury Total Minor --
Injury Total None --
Injury Total Serious 1
Injury Total All 3
Investigating Agency NTSB
NTSB Docket Number (internal use) 22047
NTSB Notification Source FAA
NTSB Notification Date Aug 17 2005 12:00AM
NTSB Notification Time --
Fiche Number and/or location -used to find docket information DMS
Date of most recent change to record Sep 14 2007 2:53PM
User who most recently changed record NTSB\lema
Basic weather conditions Visual Meteorological Cond
FAA District Office Federal Aviation Administration Los Angeles FSDO

Aircraft Involved

Aircraft #1

Aircraft Registration Number N7342P
NTSB Number LAX05FA271
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 Piper
Aircraft Model PA-24-250
Aircraft Series Identifier --
Aircraft Serial Number 24-2521
Certified Max Gross Weight 2800
Aircraft Category Airplane
Aircraft Registration Class --
Aircraft is a homebuilt? No
Flight Crew Seats --
Cabin Crew Seats --
Passenger Seats --
Total number of seats on the aircraft 4
Number of Engines 1
Fixed gear or retractable gear Retractable
Aircraft, Type of Last Inspection Annual
Date of Last Inspection Aug 1 2004 12:00AM
Airframe hours since last inspection 80.72
Airframe Hours 3841.32
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name John Shear
Aircraft Owner Street Address --
Aircraft Owner City Chino
Aircraft Owner State CA
Aircraft Owner Country USA
Aircraft Owner Zipcode 91701
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 TOA
Departure City Torrance
Departure State CA
Departure Country USA
Departure Time --
Departure Time Zone PDT
Destination Same as Local Flt --
Destination Airport Code CNO
Destination City Chino
Destination State CA
Destination Country USA
Specific Phase of Flight Emergency descent/landing
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Jul 31 2007 3:41PM
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 --