# NTSB LAX90LA208: Schweizer SGS 1-26B, N2423W, Truckee, CA, June 4, 1990

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Limited investigation · Final report
- Date: June 4, 1990, 15:03 local (22:03 UTC)
- Place: Truckee, CA
- Location: 39.3280° N, 120.1833° W: Placed by OpenAirDocs: center of Truckee, CA, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=39.3280&lon=-120.1833&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 1 fatal
- Status: Completed, report December 8, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 26832
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX90LA208
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/26832/pdf
- Page: https://openairdocs.org/ntsb/LAX90LA208

## Probable cause

THE PILOT'S IMPROPER DECISION TO RELEASE FROM THE TOW AIRPLANE AT AN INSUFFICIENT ALTITUDE ON THE LEE SIDE OF THE MOUNTAINS.

## Sequence of events

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

- In flight collision with object, maneuvering
  - object - tree(s)
  - weather condition - tailwind (contributing factor)
  - terrain condition - mountainous/hilly
  - weather evaluation - poor, pilot in command (cause)
  - altitude - inadequate, pilot in command (cause)

## Analysis

THE STUDENT GLIDER PILOT RELEASED FROM THE TOW AIRPLANE WITHOUT COMMUNICATING WITH THE TOW PILOT. THE GLIDER PROCEEDED IN A NORTHEAST DIRECTION TOWARD THE LEE SIDE OF THE MOUNTAINS. THE SURFACE WIND WAS FROM THE SOUTHWEST. THE GLIDER WAS OBSERVED AT A LOW ALTITUDE DISAPPEARING OVER A RIDGE. THE AIRCRAFT STRUCK A 50 FT TREE ABOUT 10 FEET FROM THE TOP THEN COLLIDED WITH THE GROUND.

## Aircraft

- Registration: [N2423W](https://openairdocs.org/deregistered/N2423W-2014-09-19), registration cancelled 2014-09-19, S/N 355, built 1966 (OpenAirDocs)
- Reported make and model: SCHWEIZER SGS 1-26B
- Registry model: [Schweizer SGS 1-26B](https://openairdocs.org/model/schweizer-sgs-1-26b) (registry code 8050118) (OpenAirDocs)
- Registry engine: [NONE](https://openairdocs.org/engine/none) (registry code 00000, none) (OpenAirDocs)
- Category: Glider
- Serial number: 355
- Airframe hours: 1958
- Engines: UNKNOWN UNKNOWN unknown
- Damage: Substantial damage
- Flight: Instructional, Part 91
- Operator: Robert L. Tanner
- Registered owner: David Soom
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, May 2, 1989, 64 hours before

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 68; student; medical: unknown, unknown; flight hours: 62 total, 3 in the last 90 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 210° at 10 knots
- Visibility: 20 statute miles
- Lowest ceiling: none
- Temperature: -0 °F, dew point -0 °F

## 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 19900604018369A](https://openairdocs.org/incident/19900604018369A), Jun 4, 1990: Scwzer SGS126B, Truckee, CA, Substantial damage, 1 fatal. Released tow at low altitude. Unable to get a thermal. Struck a tree landing in a field. Glider out of annual.

## Other investigations on N2423W (1)

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.

- [NTSB OAK73DXQ30](https://openairdocs.org/ntsb/OAK73DXQ30), Apr 17, 1973: Schweizer SGS126 (N2423W), Carson City, NV, substantial damage

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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