Let L-13 accident near Boynton Beach, Florida, May 4, 1992
On May 4, 1992 at about 8:00 pm local time, a Let L-13 (glider), registered N99946, was substantially damaged in an accident near Boynton Beach, Florida (Willis Gliderport airport). It was an instructional flight under general aviation rules (Part 91). 1 person had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
PREMATURE EXTENSION OF THE SPOILERS BY THE PILOT DURING APPROACH TO LAND. CONTRIBUTING TO THE ACCIDENT WAS HIS LACK OF TOTAL EXPERIENCE IN THE TYPE OF AIRCRAFT AND IN-FLIGHT ENCOUNTER WITH A DOWNDRAFT.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- May 4, 1992 · about 8:00 pm local time
- Place
- Boynton Beach, Florida · Willis Gliderport · map
- Type
- Accident
- Injuries
- 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Let L-13 · all L-13s on the register
- Registration
- N99946 · no longer on the register · serial 025822
- Damage
- Substantial damage
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
THE FLT TURNED BASE WITH PARTIAL SPOILERS EXTENDED THEN TURNED FINAL, & ENCOUNTERED A 'SEVERE DOWNDRAFT.' THE PLT RETRACTED THE SPOILERS BUT THE DESCENT CONTINUED UNTIL IMPACT WITH TREES APPROXIMATELY 300 FT SHORT OF THE RWY. HE HAD ACCUMULATED 3 HRS TOTAL TIME MAKE & MODEL DURING 8 DUAL & 12 SOLO FLIGHTS IN THE PRECEDING 30 DAYS.
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: airline transport pilot, flight instructor, commercial pilot
- Ratings: multi-engine land; multi-engine sea; single-engine land; single-engine sea; instructor: airplane multi-engine; instructor: airplane single-engine; instrument: airplane
- Flight time: 9,171 hours in all; 3 in this make and model; 430 on instruments
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: frt
The aircraft
- Airframe total time: 2,754 hours
- Last inspection: annual inspection, April 2, 1992; 18 hours since
- Maximum gross weight: 1,100 lb
- Seats: 2
- Landing gear: fixed
- Engine: (type not recorded); 0 hours total
The flight
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 260° at 10 knots, gusting 17
- Visibility: 7 statute miles
- Sky: clear
- Temperature: 88°F (31°C), dew point 52°F (11°C)
- Altimeter: 29.00 inHg
- Observation at 7:50 pm from PBI, 10 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 |
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.
Other NTSB records under N99946 the same tail number, which may have belonged to a different aircraft at the time
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 never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.