Johnson Creek Airport
Aircraft Accident/Incident Report

Yellowpine, Idaho 83677
Friday, August 7, 1998 9:15 MDT

NTSB Narrative Summary Released at Completion of Accident

Upon landing the pilot heard a bang and the right wing dropped. The airplane incurred substantial damage during a ground loop maneuver, following the separation of the right main wheel and lower strut end immediately after touchdown. Post-crash examination revealed that the lower end of the right main landing gear spring strut had broken off. Examination of the fracture surfaces revealed features characteristic of fatigue cracking in multiple locations. The fatigue cracks originated at the surface of the holes, at the edge between the wall of the hole and flat face of the leg. Separation of the spring strut was caused by fatigue cracks that originated from the surface of the two upper holes. No chamfer was found at the surfaces of the two upper holes. The surface of these holes contained for the most part a corner edge that is a stress raiser and, in turn, this stress raiser sensitized the hole to cracking. The two upper holes most likely were drilled oversize to remove anomalies such as corrosion or fretting damage. The diameter of the oversize holes was sufficient to have removed evidence of the chamfer. There was no airframe log information available which identified any maintenance on the spring strut.

NTSB Probable Cause Narrative

Right main landing gear spring strut fatigue, improper maintenance, and subsequent separation of the strut end.

Event Information

Type of Event Accident
Event Date 8/7/1998
Event Day of the Week Friday
Time of Event 915
Event Time Zone Mountain Daylight Time
Event City YELLOWPINE
Event State IDAHO
Event Country --
Zipcode of the event site 83677
Event Date Year 1998
Event Date Month 8
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude
Event Location Longitude
Event Location Airport JOHNSON CREEK
Event Location Nearest Airport ID 3U2
Indicates whether the acc/inc occurred off or on an airport On Airport
Distance from airport in statute miles 0
Degrees magnetic from airport --
Airport Elevation 4933
Weather Briefing Completeness Unknown
Investigator's weather source Weather Observation Facility
Time of the weather observation 950 Mountain Daylight Time
Direction of event from weather observation facility (degrees) 247
Weather Observation Facility ID MYL
Elevation of weather observation facility 5020
Distance of event from weather observation facility (units?) 26
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) 10
Air Temperature at event time (in degrees celsius) 20
Dew Point at event time (in degress fahrenheit) 9
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 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 3
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 1492
NTSB Notification Source --
NTSB Notification Date Aug 7 1998 12:00AM
NTSB Notification Time 940
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Dec 11 2000 11:43AM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N6437A
NTSB Number SEA98LA158
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 Cessna
Aircraft Model 182
Aircraft Series Identifier 182
Aircraft Serial Number 33237
Certified Max Gross Weight 2550
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 4
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection Annual
Date of Last Inspection Aug 1 1997 12:00AM
Airframe hours since last inspection 40
Airframe Hours 2022
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name TERWAY, WILLIAM, E.
Aircraft Owner Street Address 813 NW MONROE 3
Aircraft Owner City CORVALLIS
Aircraft Owner State OR
Aircraft Owner Country
Aircraft Owner Zipcode 97330
Operator is an individual? --
Operator Name TERWAY, WILLIAM, E.
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address 3063 NW GREENBRIAR PLACE
Operator City CORVALLIS
Operator State OR
Operator Country
Operator Zip code 97330
Operator Code
Owner has at least one certificate None
Other Operator of large aircraft? No
Certified for Part 133 or 137 Operation Unknown
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 MYL
Departure City MCCALL
Departure State ID
Departure Country
Departure Time 830
Departure Time Zone MDT
Destination Same as Local Flt crash at destination city
Destination Airport Code 3U2
Destination City
Destination State
Destination Country
Specific Phase of Flight --
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 17
Runway Length 3400
Runway Width 150
Sight Seeing flight No
Air Medical Flight No
Medical Flight --