Pitts S-1S accident near Stevensville, Maryland, July 15, 1994
On July 15, 1994 at about 6:45 pm local time, a Pitts S-1S, an amateur-built aircraft,, registered N515TN, was substantially damaged in an accident near Stevensville, Maryland (Kentmore Airpark 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
Inadequate maintenance by which undertorquing of the accessory gear retaining bolt resulted in fatigue failure of the bolt and the subsequent loss of engine power.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 15, 1994 · about 6:45 pm local time
- Place
- Stevensville, Maryland · Kentmore Airpark · map
- Type
- Accident
- Injuries
- 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Pitts S-1S, amateur-built · all S-1Ss on the register
- Registration
- N515TN · no longer on the register · serial 7-0255
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
THE AIRPLANE'S ENGINE LOST TOTAL POWER JUST AFTER TAKEOFF WHEN THE PILOT REDUCED THE THROTTLE. THE PILOT RE-APPLIED FULL THROTTLE WITH NO RESULT. DURING THE FORCED LANDING IN A FIELD, THE AIRPLANE'S WING STRUCK A TREE, AND THE AIRPLANE NOSED OVER. EXAMINATION OF THE ENGINE REVEALED THAT THE CRANKSHAFT GEAR (13S19646) BECAME DISCONNECTED FROM THE CRANKSHAFT DUE TO A BROKEN BOLT. METALLURGICAL EXAMINATION OF THE ACCESSORY GEAR RETAINING BOLT (P/N STD-2213), AND DOWEL PIN (P/N STD-1065) REVEALED THAT THEY SEPARATED AS A RESULT OF HIGH CYCLE FATIGUE MECHANISM, MOST LIKELY CAUSED BY INSUFFICIENT TORQUE OF THE BOLT.
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: single-engine land
- Flight time: 640 hours in all; 61 in this make and model; 17 in the last 90 days; 14 in the last 30 days; 345 as pilot in command
- Medical certificate: Class 3 (valid medical--w/ waivers/lim.)
- Seat: ctr
The aircraft
- Airframe total time: 144 hours
- Last inspection: annual inspection, June 10, 1994; 9 hours since
- Maximum gross weight: 1,150 lb
- Seats: 1
- Landing gear: fixed
- Engine: Lycoming O-360-A4G (piston); 0 hours total
The flight
- Departed from: 3W3 at 6:52 pm
- Destination: ESN Easton MD
- Flight plan: none
- Runway 10, 2,000 ft by 75 ft
Weather at the time
- Light: daylight
- Wind: from 090° at 8 knots
- Visibility: 5 statute miles
- Sky: not recorded; not recorded
- Temperature: 91°F (33°C), dew point 77°F (25°C)
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.