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Accidents · NTSB SEA90LA150 · Final report

Glasflugel H 301 LIBELLE accident near Thompson Falls, Montana, July 29, 1990

On July 29, 1990 at about 7:00 pm local time, a Glasflugel H 301 LIBELLE (glider), registered N4166A, was substantially damaged in an accident near Thompson Falls, Montana (Thompson Falls airport). It was a personal flight under general aviation rules (Part 91). No one was hurt; 1 person was on board or involved. The weather was visual conditions (good weather).

The NTSB's probable cause their words, unchanged

A DISABLED AIRCRAFT BLOCKING THE ACTIVE RUNWAY.

Source: NTSB aviation accident database, copy made November 2, 2026. Docket and reports at the NTSB.

What the record shows

Date
July 29, 1990 · about 7:00 pm local time · cases in 1990
Place
Thompson Falls, Montana · Thompson Falls · cases near this airport · map
Type
Accident
Injuries
No one was hurt; 1 person was on board or involved.
Weather
visual conditions (good weather)
Aircraft
Glasflugel H 301 LIBELLE H 301 LIBE · all H 301 LIBELLEs on the register
Registration
N4166A · registry record · serial 52
Damage
Substantial damage
Flight
Personal flight · general aviation rules (Part 91)

The NTSB's narrative final · quoted from the NTSB record

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.

The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.

The factual record from the NTSB's investigation tables, in plain English

Pilot

  • Certificate: private
  • Ratings: rotorcraft: glider
  • Flight time: 249 hours in all; 11 in this make and model; 23 in the last 90 days; 11 in the last 30 days; 239 as pilot in command
  • Medical certificate: Class 3 (valid medical--no waivers/lim.)
  • Seat: ctr

The aircraft

  • Airframe total time: 1,608 hours
  • Last inspection: annual inspection, October 28, 1989; 64 hours since
  • Maximum gross weight: 660 lb
  • Seats: 1
  • Landing gear: retractable
  • Engine: (type not recorded); 0 hours total

The flight

  • Flight plan: none
  • Runway 7, 2,200 ft by 50 ft

Weather at the time

  • Light: daylight
  • Wind: from 020° at 8 knots
  • Visibility: 40 statute miles
  • Sky: clear
  • Temperature: 61°F (16°C), dew point 52°F (11°C)
  • Altimeter: 30.00 inHg
  • Observation at 6:50 pm from FCA, 60 miles away

Injuries

FatalSeriousMinorNone
Crew1

Documents from the investigation the NTSB's docket: the evidence folder behind the report

The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.

Connections how this case links to the rest of the register

Aircraft
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Analytics

The whole map of how records connect · these connections as data: /graph/accident/SEA90LA150.json.

The bigger picture in Aviation Analytics: accidents over time since 1982, by model, by phase of flight and conditions, by place and on the map.

Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text does not name anyone involved, its policy at this time. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.