Amateur-built T-51 MUSTANG KIT accident near St Francis, Kansas, June 11, 2013
On June 11, 2013 at about 2:15 pm local time, a 2012 amateur-built T-51 MUSTANG KIT, registered N548RR, was substantially damaged in an accident during maneuvering near St Francis, Kansas (Cheyenne County Muni airport). It was a flight test 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
Foreign debris in the propeller governor, which led to excessive wear in the governor and its subsequent in-flight failure.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- June 11, 2013 · about 2:15 pm local time
- Place
- St Francis, Kansas · Cheyenne County Muni · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built T-51 MUSTANG KIT, built 2012
- Registration
- N548RR · no longer on the register · serial M08SV6SOHK0142
- Damage
- Substantial damage
- Flight
- Flight test · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot had been flying the amateur-built airplane for about 15 minutes at a cruise altitude of between 4,000 and 5,000 ft when he attempted to slow the engine rpm by pulling the propeller control back; however, this had no effect on the engine rpm. The pilot attempted to slow the rpm several times, but the propeller then cycled to "full bite" and remained that way until he performed a wheels-up landing on a rough road. The airplane had accumulated 50 hours of total flight time at the time of the accident. During a postaccident test run, the engine ran normally. Oil was drained from the propeller gearbox, and it presented a used appearance. The propeller governor was subsequently bench tested and did not meet the manufacturer's test specifications. A disassembly of the governor revealed the presence of foreign debris and wear marks on several parts of the governor. After the governor was cleaned and reassembled, it was bench tested again, and it operated normally. The pilot reported that, after the accident, the airplane was repaired, the engine and a new governor were installed, and the airplane operated without any anomalies. The foreign debris likely caused excessive wear inside the propeller governor, which subsequently led to its in-flight failure.
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
What happened, in order
- Powerplant sys/comp malf/fail during maneuvering defining event
- Loss of engine power (total) during maneuvering
- Off-field or emergency landing during emergency descent
- Collision with terrain or object (not controlled flight into terrain) during emergency descent
The NTSB's findings
- cause Aircraft › Aircraft propeller/rotor › Propeller system › Propeller governor › Fatigue/wear/corrosion
- Environmental issues › Physical environment › Terrain › Rough terrain › Contributed to outcome
- factor Aircraft › Fluids/misc hardware › Fluids › Oil › Fluid condition
- Aircraft › Fluids/misc hardware › Fluids › Oil › Fluid condition
Pilot
- Certificate: private
- Ratings: single-engine land
- Flight time: 2,415 hours in all; 50 in this make and model; 52.5 in the last 90 days; 17.7 in the last 30 days; 2,415 as pilot in command
- Last flight review: August 1, 2011
- Medical certificate: Class 3 (with waivers/limitations)
- Seat: frt
- Injury: no injuries
The aircraft
- Airframe total time: 50 hours
- Last inspection: condition inspection, March 15, 2013
- Maximum gross weight: 1,850 lb
- Seats: 2
- Landing gear: retractable
- Engine: Honda 3.5 L (piston); 50 hours total
The flight
- Departed from: SYF St Francis KS at 2:00 pm
- Destination: SYF St Francis KS
- Flight plan: not recorded
Weather at the time
- Light: daylight
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 81°F (27°C), dew point 50°F (10°C)
- Altimeter: 29.78 inHg
- Observation at 2:35 pm from SYF, 2 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight 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.