# NTSB SEA90LA150: Glasflugel H 301 Libelle, N4166A, Thompson Falls, MT, July 29, 1990

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: July 29, 1990, 13:00 local (19:00 UTC)
- Place: Thompson Falls, MT
- Coordinates: 47.560333, -115.439735 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=47.5603&lon=-115.4397&mi=10
- Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report December 30, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 41252
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA90LA150
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/41252/pdf
- Page: https://openairdocs.org/ntsb/SEA90LA150

## Probable cause

A DISABLED AIRCRAFT BLOCKING THE ACTIVE RUNWAY.

## Sequence of events

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

- Undershoot, approach - vfr pattern - final approach
  - object - aircraft parked/standing (cause)
  - remedial action - attempted, pilot in command
  - proper touchdown point - not attained, pilot in command
- In flight collision with terrain/water, approach - vfr pattern - final approach

## Analysis

WHILE THE PILOT WAS ON DOWNWIND IN THE TRAFFIC PATTERN FOR LANDING, A GLIDER AHEAD IN THE PATTERN BLEW A TIRE ON TOUCHDOWN AND WAS SITTING DISABLED ON THE RUNWAY. THE PILOT ATTEMPTED TO LAND ON THE UNOBSTRUCTED PORTION OF RWY, BUT TOUCHED DOWN ABOUT 75 FEET SHORT OF THE RUNWAY.

## Aircraft

- Registration: [N4166A](https://openairdocs.org/aircraft/N4166A), registered now, S/N 52, built 1967 (OpenAirDocs)
- Reported make and model: GLASFLUGEL H 301 LIBELLE (H 301 LIBE)
- Registry model: [Glasflugel H 301 LIBELLE](https://openairdocs.org/model/glasflugel-h-301-libelle) (registry code 3800337) (OpenAirDocs)
- Registry engine: [Amateur-built UNKNOWN ENG](https://openairdocs.org/engine/amateur-built-unknown-eng) (registry code 99999) (OpenAirDocs)
- Category: Glider
- Serial number: 52
- Airframe hours: 1608
- Engines: unknown
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Dale Walker
- Registered owner: Unknown
- Airworthiness certificate: Special, Experimental (Special)
- Last inspection: Annual, October 28, 1989, 64 hours before
- Airport: THM, Thompson Falls, runway 7, 2,200 × 50 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 46; private; medical: class 3, valid medical--no waivers/lim.; seat: center; flight hours: 249 total, 11 in this make and model, 239 as pilot in command, 23 in the last 90 days, 11 in the last 30 days, 3 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 20° at 8 knots
- Visibility: 40 statute miles
- Lowest ceiling: none
- Temperature: 61 °F, dew point 52 °F
- Altimeter: 30.00 inHg
- Observed at: FCA, 60 nm away

## 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 19900729037459A](https://openairdocs.org/incident/19900729037459A), Jul 29, 1990: Glasfl H301LIBELLE, Thompson Falls, MT, Substantial damage. Runway blocked. Extended downwind using spoilers. Too low. Hit wires on top fence. Rolled left and hit ground.

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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