Amateur-built S-51 accident near Forty Fort, Pennsylvania, June 9, 2000
On June 9, 2000 at about 12:50 pm local time, a amateur-built S-51, registered N51FY, was substantially damaged in an accident near Forty Fort, Pennsylvania (Wyoming Valley Airport). It was a personal 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
The owner/builder's inadequate design, resulting in total failure of the reduction gear assembly accessory drive shaft.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- June 9, 2000 · about 12:50 pm local time
- Place
- Forty Fort, Pennsylvania · Wyoming Valley Airport · map
- Type
- Accident
- Injuries
- 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built S-51
- Registration
- N51FY · no longer on the register · serial 001
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
During takeoff, approximately 150 above the ground, the propeller reduction gearbox input shaft failed, and the airplane lost all power. The pilot performed a forced landing to a field where the airplane struck a fence. After reviewing the wreckage, the pilot stated that he machined his own shaft for the home built airplane. He stated that he machined the shaft too thin, and after about 150 hours of operation, it failed at its weakest point. The kit manufacturer stated that the production model shafts are larger, and used aviation splines, whereas the accident airplane had a smaller shaft that used automotive splines.
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: commercial pilot
- Ratings: multi-engine land; single-engine land; instrument: airplane
- Flight time: 4,004 hours in all; 200 in this make and model; 26 in the last 90 days
- Last flight review: March 20, 1999
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: frt
- Injury: minor injuries
The aircraft
- Airframe total time: 150 hours
- Last inspection: annual inspection
- Maximum gross weight: 3,694 lb
- Seats: 2
- Landing gear: retractable
- Engine: General Motors GM 350 (piston); 0 hours total
The flight
- Departed from: WBW Forty Fort PA at 12:50 pm
- Flight plan: none
- Runway 25, 3,376 ft by 75 ft
Weather at the time
- Light: daylight
- Wind: from 220° at 10 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 73°F (23°C), dew point 57°F (14°C)
- Altimeter: 30.04 inHg
- Observation at 12:54 pm from AVP, 6 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.
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.