Stark's Twin Oaks Airpark Airport
Aircraft Accident/Incident Report

Hillsboro, Oregon 97123
Thursday, February 5, 1998 14:55 PST

NTSB Narrative Summary Released at Completion of Accident

The pilot reported that after takeoff he remained in the traffic pattern and that he 'was too low on final approach and (the) wheels struck (the) slope leading to (the) end of (the) runway.' The airport manager reported that tire marks from the aircraft were observed approximately 30 feet short of the paved physical end of runway 02 which has a painted displaced threshold of 100 feet (north of its physical end). The landing gear then collapsed and the aircraft skidded down the runway on its belly during which it slid off the west side of the pavement.

NTSB Probable Cause Narrative

The pilot's failure to maintain a proper glidepath.

Event Information

Type of Event Accident
Event Date 2/5/1998
Event Day of the Week Thursday
Time of Event 1455
Event Time Zone Pacific Standard Time
Event City HILLSBORO
Event State OREGON
Event Country --
Zipcode of the event site 97123
Event Date Year 1998
Event Date Month 2
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude
Event Location Longitude
Event Location Airport STARK'S TWIN OAKS AIRPARK
Event Location Nearest Airport ID 7S3
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 170
Weather Briefing Completeness Unknown
Investigator's weather source Weather Observation Facility
Time of the weather observation 1450 Pacific Standard Time
Direction of event from weather observation facility (degrees) 338
Weather Observation Facility ID HIO
Elevation of weather observation facility 204
Distance of event from weather observation facility (units?) 6
Time Zone of the weather observation PST
Lighting Conditions Day
Lowest Ceiling Height 8000
Lowest Non-Ceiling Height 5000
Sky/Lowest/Cloud Conditions Scattered
Sky Condition for Lowest Ceiling Broken
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 15
Air Temperature at event time (in degrees celsius) 14
Dew Point at event time (in degress fahrenheit) 7
Wind Direction (degrees magnetic) 0
Variable Wind Indicator Variable
Wind Speed (knots) 5
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 Minor
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal --
Injury Total Minor 1
Injury Total None --
Injury Total Serious --
Injury Total All 1
Investigating Agency NTSB
NTSB Docket Number (internal use) 852
NTSB Notification Source --
NTSB Notification Date Feb 6 1998 12:00AM
NTSB Notification Time 730
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Dec 11 2000 10:48AM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N55740
NTSB Number SEA98LA035
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 BROMLEY
Aircraft Model STEEN SKYBOLT
Aircraft Series Identifier STEEN SKYB
Aircraft Serial Number 10GB
Certified Max Gross Weight 1650
Aircraft Category Airplane
Aircraft Registration Class U.S. Registered/U.S. Soil
Aircraft is a homebuilt? Yes
Flight Crew Seats --
Cabin Crew Seats --
Passenger Seats --
Total number of seats on the aircraft 2
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection Annual
Date of Last Inspection May 13 1997 12:00AM
Airframe hours since last inspection 52
Airframe Hours 640
ELT Installed Yes
ELT Activated Yes
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name PIERSON, JACK, L.
Aircraft Owner Street Address 22955 SW HILLSBORO HIGHWAY
Aircraft Owner City NEWBERG
Aircraft Owner State OR
Aircraft Owner Country
Aircraft Owner Zipcode 97132
Operator is an individual? --
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? 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 Yes
Departure Airport Code 7S3
Departure City
Departure State
Departure Country
Departure Time 1450
Departure Time Zone PST
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 Landing
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 2
Runway Length 2465
Runway Width 50
Sight Seeing flight No
Air Medical Flight No
Medical Flight --