Aircraft Accident/Incident Report

Roberts, Idaho 83444
Monday, July 17, 1995 8:15 MDT

NTSB Narrative Summary Released at Completion of Accident

THE PILOT REPORTED THAT SHORTLY AFTER TAKEOFF, AT 40 FEET ABOVE GROUND LEVEL, THE ENGINE LOST POWER AND BEGAN BACKFIRING. THE PILOT MADE A FORCED LANDING IN A BARLEY FIELD WITH 3-FOOT-TALL CROPS, AND THE AIRPLANE CARTWHEELED. POSTACCIDENT EXAMINATION OF THE ENGINE REVEALED THAT THE EXHAUST VALVE ROCKER ARM HOUSING ON THE NUMBER 3 CYLINDER SEPARATED, DISABLING THE NUMBER 3 CYLINDER EXHAUST VALVE.

NTSB Probable Cause Narrative

A LOSS OF ENGINE POWER DUE TO THE SEPARATION OF THE NUMBER 3 CYLINDER EXHAUST VALVE ROCKER ARM SHAFT FROM THE CYLINDER HEAD, WHICH DISABLED MOVEMENT OF THE EXHAUST VALVE. A FACTOR WAS THE LACK OF SUITABLE TERRAIN FOR THE FORCED LANDING.

Event Information

Type of Event Accident
Event Date 7/17/1995
Event Day of the Week Monday
Time of Event 815
Event Time Zone Mountain Daylight Time
Event City ROBERTS
Event State IDAHO
Event Country --
Zipcode of the event site 83444
Event Date Year 1995
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 745 Mountain Daylight Time
Direction of event from weather observation facility (degrees) 160
Weather Observation Facility ID IDA
Elevation of weather observation facility 4740
Distance of event from weather observation facility (units?) 12
Time Zone of the weather observation MDT
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) 60
Air Temperature at event time (in degrees celsius) 14
Dew Point at event time (in degress fahrenheit) 9
Wind Direction (degrees magnetic) 350
Variable Wind Indicator Unknown
Wind Speed (knots) 5
Wind Velocity Indicator Unknown
Wind Gust Indicator Unknown
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) 30
Density Altitude (feet) 5390
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) 1192
NTSB Notification Source --
NTSB Notification Date Jul 18 1995 12:00AM
NTSB Notification Time 1325
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Dec 7 2000 4:26PM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N4326S
NTSB Number SEA95LA154
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 AIR TRACTOR
Aircraft Model AT-301
Aircraft Series Identifier AT-301
Aircraft Serial Number 301-0006
Certified Max Gross Weight 5000
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 Apr 7 1995 12:00AM
Airframe hours since last inspection 202
Airframe Hours 7174
ELT Installed No
ELT Activated Unknown
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name LEWIS, ORLIN & JULIA
Aircraft Owner Street Address P.O. BOX 6
Aircraft Owner City LEWISVILLE
Aircraft Owner State ID
Aircraft Owner Country
Aircraft Owner Zipcode 83431
Operator is an individual? --
Operator Name
Operator Same as Owner? Yes
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address
Operator City
Operator State
Operator Country
Operator Zip code
Operator Code HNBG
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 --
Indicates Domestic or International Flight --
Operator carrying Pax/Cargo/Mail --
Type of Flying (Per_Bus / Primary) Positioning
Second Pilot on Board No
Departure Point Same as Event Yes
Departure Airport Code
Departure City
Departure State
Departure Country
Departure Time 0
Departure Time Zone
Destination Same as Local Flt --
Destination Airport Code U56
Destination City RIGBY
Destination State ID
Destination Country
Specific Phase of Flight Takeoff
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 --