Custer County Airport
Aircraft Accident/Incident Report

Custer, South Dakota 57730
Monday, March 6, 1989 17:30 MST

NTSB Narrative Summary Released at Completion of Accident

THE PRIVATE PLT WAS PERFORMING A FLIGHT FOLLOWING HIS INSTALLATION OF TWO MAGNETOS. A WITNESS AND THE PLT REPORTED THAT ON CLIMB OUT THE ENGINE QUIT. THE PLT SAID HE HEARD SOMETHING BREAK IN THE ENGINE. THE PLT ATTEMPTED TO LAND ON A GRAVEL DRIVEWAY SOUTH OF THE RUNWAY. AT IMPACT, THE MAIN LANDING GEAR COLLAPSED. THE PLANE CAME TO REST AFTER SLIDING 150 FT. A POST ACCIDENT INSPECTION REVEALED THAT BOTH MAGNETOS HAD BEEN INSTALLED WITHOUT COTTER PINS ON THE DRIVE GEAR RETAINING NUTS. THIS RESULTED IN THE NUTS BACKING OFF, DISCONNECTING THE MAGNETOS, AND ONE OF THE GEARS FALLING INTO THE ENGINE, RESULTING IN THE REPORTED STOPPAGE.

NTSB Probable Cause Narrative

THE IMPROPER MAINTENANCE BY THE PILOT IN COMMAND/OWNER IN THAT THE MAGNETO DRIVE GEAR RETAINING NUTS WERE NOT SAFETIED WHICH RESULTED IN THEM BACKING OFF, DISCONNECTING THE MAGNETOES AND ONE OF THE GEARS FALLING INTO THE ENGINE.

Event Information

Type of Event Accident
Event Date 3/6/1989
Event Day of the Week Monday
Time of Event 1730
Event Time Zone Mountain Standard Time
Event City CUSTER
Event State SOUTH DAKOTA
Event Country --
Zipcode of the event site 57730
Event Date Year 1989
Event Date Month 3
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude
Event Location Longitude
Event Location Airport CUSTER COUNTY
Event Location Nearest Airport ID SD01
Indicates whether the acc/inc occurred off or on an airport Off Airport/Airstrip
Distance from airport in statute miles 0
Degrees magnetic from airport 0
Airport Elevation 0
Weather Briefing Completeness Unknown
Investigator's weather source Pilot
Time of the weather observation 0
Direction of event from weather observation facility (degrees) 0
Weather Observation Facility ID
Elevation of weather observation facility 0
Distance of event from weather observation facility (units?) 0
Time Zone of the weather observation
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) 25
Air Temperature at event time (in degrees celsius) 10
Dew Point at event time (in degress fahrenheit) --
Wind Direction (degrees magnetic) 0
Variable Wind Indicator Variable
Wind Speed (knots) 0
Wind Velocity Indicator Light and Variable
Wind Gust Indicator Not Gusting
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) --
Density Altitude (feet) --
Intensity of Precipitation Unknown
METAR weather report --
Event Highest Injury Serious
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal --
Injury Total Minor --
Injury Total None --
Injury Total Serious 1
Injury Total All 1
Investigating Agency NTSB
NTSB Docket Number (internal use) 377
NTSB Notification Source --
NTSB Notification Date Mar 6 1989 12:00AM
NTSB Notification Time 2003
Fiche Number and/or location -used to find docket information 38756
Date of most recent change to record Dec 13 2000 12:31PM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N150C
NTSB Number DEN89LA082
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 STINSON
Aircraft Model 108-2
Aircraft Series Identifier 108-2
Aircraft Serial Number 108-3150
Certified Max Gross Weight 2230
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 Jan 27 1989 12:00AM
Airframe hours since last inspection 3
Airframe Hours 1356
ELT Installed Yes
ELT Activated Yes
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name JAMES R. WINTER
Aircraft Owner Street Address HCR 83 BOX 56A
Aircraft Owner City CUSTER
Aircraft Owner State SD
Aircraft Owner Country
Aircraft Owner Zipcode 57730
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 SD01
Departure City CUSTER
Departure State SD
Departure Country
Departure Time 1720
Departure Time Zone MST
Destination Same as Local Flt dest & departure same, accident can occur anywhere
Destination Airport Code SD01
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 10:35AM
User who most recently changed record dbo
Since inspection or accident --
Event Location Runway Number and Location 0
Runway Length 0
Runway Width 0
Sight Seeing flight No
Air Medical Flight No
Medical Flight --