Aircraft Accident/Incident Report

Lake Cobb, California 95426
Sunday, April 7, 1991 15:00 PDT

NTSB Narrative Summary Released at Completion of Accident

AFTER THE AERO TOW RELEASED THE PILOT SOARED TO MT. ST. HELENA AND THEN ONTO COBB MOUNTAIN WHERE THERMAL LIFT WAS REPORTED. UPON ARRIVING OVER COBB MOUNTAIN HE DID NOT ENCOUNTER ANY THERMAL LIFT. REALIZING A FORCED LANDING WAS IMMINENT THE PILOT SELECTED A OFF-FIELD LANDING AREA WHICH WAS SURROUNDED ON THREE SIDES. THE PILOT REPORTED THAT THE NORTHWEST SIDE OF THE FIELD WAS UNOBSTRUCTED EXCEPT FOR A SMALL WIRE FENCE WHICH POSED NO PROBLEM FOR THE OFF-FIELD LANDING. THE PILOT FAILED TO SEE A SMALL TRANSMISSION WIRE WHICH CROSSED THE FINAL APPROACH COURSE ABOUT 25 FEET ABOVE GROUND LEVEL. THE GLIDER STRUCK THE WIRE WHICH CAUSED THE GLIDER TO NOSE DOWN ABOUT 40 DEGREES AND STRIKE THE GROUND IN A WINGS LEVEL ATTITUDE.

NTSB Probable Cause Narrative

THAT THE PILOT'S VISUAL LOOKOUT WAS IMPROPER. CONTRIBUTING TO THIS ACCIDENT WAS THE UNMARKED TRANSMISSION WIRE.

Event Information

Type of Event Accident
Event Date 4/7/1991
Event Day of the Week Sunday
Time of Event 1500
Event Time Zone Pacific Daylight Time
Event City LAKE COBB
Event State CALIFORNIA
Event Country --
Zipcode of the event site 95426
Event Date Year 1991
Event Date Month 4
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 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) 50
Air Temperature at event time (in degrees celsius) --
Dew Point at event time (in degress fahrenheit) --
Wind Direction (degrees magnetic) 345
Variable Wind Indicator Unknown
Wind Speed (knots) 0
Wind Velocity Indicator Light and Variable
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 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) 369
NTSB Notification Source --
NTSB Notification Date --
NTSB Notification Time 0
Fiche Number and/or location -used to find docket information 43655
Date of most recent change to record Dec 12 2000 9:44AM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N81PT
NTSB Number LAX91LA163
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 SCHEMPP-HIRTH
Aircraft Model VENTUS B/16.6
Aircraft Series Identifier VENTUS B/1
Aircraft Serial Number 258
Certified Max Gross Weight 1102
Aircraft Category Glider
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 0
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 --
ELT Installed Unknown
ELT Activated Unknown
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name RICHARD CARTER
Aircraft Owner Street Address 104 BRAE CT.
Aircraft Owner City SUISUN
Aircraft Owner State CA
Aircraft Owner Country
Aircraft Owner Zipcode 94585
Operator is an individual? --
Operator Name RICHARD CARTER
Operator Same as Owner? Yes
Operator Is Doing Business As --
Operator Address Same as Owner? Yes
Operator Street Address 104 BRAE CT.
Operator City SUISUN
Operator State CA
Operator Country
Operator Zip code 94585
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
Departure City VACAVILLE
Departure State CA
Departure Country
Departure Time 1200
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 Approach
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 --