# NTSB LAX91LA163: Schempp-Hirth Ventus B/16.6, N81PT, Lake Cobb, CA, April 7, 1991

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: April 7, 1991, 15:00 local (22:00 UTC)
- Place: Lake Cobb, CA
- Coordinates: 38.830223, -122.710174 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=38.8302&lon=-122.7102&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor
- Status: Completed, report December 30, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 27163
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX91LA163
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/27163/pdf
- Page: https://openairdocs.org/ntsb/LAX91LA163

## Probable cause

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

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- In flight encounter with weather, maneuvering
  - weather condition - no thermal lift (contributing factor)
- Forced landing, descent - emergency
- In flight collision with object, approach - vfr pattern - final approach
  - object - wire,transmission
  - visual lookout - improper, pilot in command (cause)

## Analysis

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.

## Aircraft

- Registration: [N81PT](https://openairdocs.org/aircraft/N81PT), registered now, S/N 258 (OpenAirDocs)
- Reported make and model: SCHEMPP-HIRTH VENTUS B/16.6 (VENTUS B/1)
- Registry model: [Schempp-Hirth VENTUS B/16.6](https://openairdocs.org/model/schempp-hirth-ventus-b-16-6) (registry code 3802061) (OpenAirDocs)
- Registry engine: [NONE](https://openairdocs.org/engine/none) (registry code 00000, none) (OpenAirDocs)
- Category: Glider
- Serial number: 258
- Engines: unknown
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Richard Carter
- Registered owner: Richard Carter
- Last inspection: Unknown, January 2, 2000
- Departed: VACAVILLE, CA

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 66; airline transport, commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 3, valid medical--w/ waivers/lim; flight hours: 23,125 total, 355 in this make and model, 17,055 as pilot in command, 9 in the last 90 days, 4 in the last 30 days, 3 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Visibility: 50 statute miles
- Lowest ceiling: none

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Accident 19910407008989A](https://openairdocs.org/incident/19910407008989A), Apr 7, 1991: Sphrth VENTUSB, Lake Cobb, CA, Substantial damage. Soaring over mountains ran out of thermals. Struck hidden wire off airport landing. Failed see wire.

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

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