Aircraft Accident/Incident Report

Gridley, California 95948
Tuesady, July 11, 2000 10:30 PST

NTSB Narrative Summary Released at Completion of Accident

While maneuvering during an aerial application flight, the pilot heard an unusual engine noise, experienced a loss of engine oil pressure, observed smoke, and lost partial power. The pilot made a precautionary landing on a nearby field road. During rollout, the airplane collided with a dirt berm. An inspection of the engine revealed its No. 2 cylinder exhaust valve head had separated and it broke the cylinder. The engine's total time was estimated at 9,300 hours, and it had been operated about 708.8 hours since last receiving a major overhaul.

NTSB Probable Cause Narrative

A partial loss of engine power due to the failure of an exhaust valve during an aerial application flight.

Event Information

Type of Event Accident
Event Date 7/11/2000
Event Day of the Week Tuesday
Time of Event 1030
Event Time Zone Pacific Standard Time
Event City GRIDLEY
Event State CALIFORNIA
Event Country --
Zipcode of the event site 95948
Event Date Year 2000
Event Date Month 7
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 1753 Pacific Daylight Time
Direction of event from weather observation facility (degrees) 10
Weather Observation Facility ID OVE
Elevation of weather observation facility 192
Distance of event from weather observation facility (units?) 8
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) 10
Air Temperature at event time (in degrees celsius) 79
Dew Point at event time (in degress fahrenheit) 55
Wind Direction (degrees magnetic) 290
Variable Wind Indicator Unknown
Wind Speed (knots) 4
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) 10699
NTSB Notification Source FAA
NTSB Notification Date Jul 11 2000 12:00AM
NTSB Notification Time 1100
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Oct 9 2001 3:21PM
User who most recently changed record NTSB\MONR
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N897X
NTSB Number LAX00LA261
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 137: Agricultural
Type of Flight Plan filed None
Flight plan Was Activated? --
Damage Substantial
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name Grumman
Aircraft Model G-164A
Aircraft Series Identifier G-164A
Aircraft Serial Number 419
Certified Max Gross Weight 4500
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 1
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection Annual
Date of Last Inspection Jun 15 2000 12:00AM
Airframe hours since last inspection 45
Airframe Hours 12245
ELT Installed Unknown
ELT Activated Unknown
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name CLARENCE WILLIAMS
Aircraft Owner Street Address
Aircraft Owner City BUTTE
Aircraft Owner State CA
Aircraft Owner Country
Aircraft Owner Zipcode 95917
Operator is an individual? --
Operator Name WILLIAMS AG SERVICE, INC.
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address PO BOX 474
Operator City BIGGS
Operator State CA
Operator Country
Operator Zip code 95917
Operator Code NHWG
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) Aerial Application
Second Pilot on Board No
Departure Point Same as Event No
Departure Airport Code
Departure City BIGGS
Departure State CA
Departure Country
Departure Time 1040
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 Maneuvering
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Sep 23 2001 4:00AM
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 --