Aircraft Accident/Incident Report

El Mirage, California 95694
Tuesady, October 6, 1992 11:00 PDT

NTSB Narrative Summary Released at Completion of Accident

THE PILOT WAS CONDUCTING A LOCAL PERSONAL FLIGHT OVER A DRY LAKE TO TEST A MODIFICATION ON THE MOTORIZED GLIDER. THE PILOT TOLD FRIENDS THAT HE INTENDED TO 'DO SOME STALLS.' AFTER EXECUTING SOME BASIC TURNS AND TAKEOFFS AND LANDING, THE PILOT DEPARTED THE AREA. A WITNESS OBSERVED THE AIRCRAFT IN A SPIN AND SAW IT CRASH. THE PILOT/OWNER RECENTLY INSTALLED A VERTICAL STABILIZER BETWEEN THE EXISTING RUDDERVATORS FOR BETTER LATERAL STABILITY IN THE MOTORIZED GLIDER. EXAMINATION OF THE WRECKAGE DISCLOSED NO EVIDENCE OF ANY PREEXISTING CONTROL MALFUNCTIONS OR FAILURES. A HOME BUILT DESIGN ENGINEER REPORTED THAT THE INCLUSION OF THE VERTICAL STABILIZER WOULD ADVERSELY EFFECT THE SPIN RECOVERY CHARACTERISTICS OF THE AIRCRAFT BY BLANKING OUT THE SIDE OF THE RUDDERVATOR OPPOSITE TO THE SPIN.

NTSB Probable Cause Narrative

THE PILOT/OWNER'S IMPROPER INSTALLATION OF THE VERTICAL STABILIZER. CONTRIBUTING TO THIS ACCIDENT WAS THE PILOT'S INTENTIONAL STALL, INADVERTENT SPIN, AND INABILITY TO RECOVER FROM THE SPIN DUE TO THE INADEQUATE EQUIPMENT (VERTICAL STABILIZER) DESIGN.

Event Information

Type of Event Accident
Event Date 10/6/1992
Event Day of the Week Tuesday
Time of Event 1100
Event Time Zone Pacific Daylight Time
Event City EL MIRAGE
Event State CALIFORNIA
Event Country --
Zipcode of the event site 95694
Event Date Year 1992
Event Date Month 10
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 0
Degrees magnetic from airport 0
Airport Elevation --
Weather Briefing Completeness Unknown
Investigator's weather source Witness
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) 40
Air Temperature at event time (in degrees celsius) 29
Dew Point at event time (in degress fahrenheit) --
Wind Direction (degrees magnetic) 0
Variable Wind Indicator Unknown
Wind Speed (knots) 0
Wind Velocity Indicator Calm
Wind Gust Indicator Unknown
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) --
Density Altitude (feet) --
Intensity of Precipitation Unknown
METAR weather report --
Event Highest Injury Fatal
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal 1
Injury Total Minor --
Injury Total None --
Injury Total Serious --
Injury Total All 1
Investigating Agency NTSB
NTSB Docket Number (internal use) 665
NTSB Notification Source --
NTSB Notification Date Oct 6 1992 12:00AM
NTSB Notification Time 1200
Fiche Number and/or location -used to find docket information 48062
Date of most recent change to record Dec 11 2000 3:23PM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N4663A
NTSB Number LAX93LA005
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed None
Flight plan Was Activated? --
Damage Destroyed
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name SWICH
Aircraft Model II
Aircraft Series Identifier II
Aircraft Serial Number 2
Certified Max Gross Weight --
Aircraft Category Glider
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 1
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection Unknown
Date of Last Inspection Jan 2 2000 12:00AM
Airframe hours since last inspection --
Airframe Hours 72
ELT Installed No
ELT Activated Unknown
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name IRWIN, THOMAS M.
Aircraft Owner Street Address 4826 E. VISTA STREET
Aircraft Owner City LONG BEACH
Aircraft Owner State CA
Aircraft Owner Country
Aircraft Owner Zipcode 90803
Operator is an individual? --
Operator Name IRWIN, THOMAS M.
Operator Same as Owner? Yes
Operator Is Doing Business As --
Operator Address Same as Owner? Yes
Operator Street Address 4826 E. VISTA STREET
Operator City LONG BEACH
Operator State CA
Operator Country
Operator Zip code 90803
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
Departure City
Departure State
Departure Country
Departure Time 830
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 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 --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --