Amateur-built T-51 accident near Dekalb, Illinois, December 11, 2012
On December 11, 2012 at about 9:45 pm local time, a amateur-built T-51, registered N512JA, was substantially damaged in an accident during enroute (climb to cruise) near Dekalb, Illinois (De Kalb Taylor Municipal Airpo airport). It was a flight test under general aviation rules (Part 91). 1 person was seriously injured. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The improper engine overhaul by the airplane kit manufacturer, which resulted in a catastrophic engine failure.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- December 11, 2012 · about 9:45 pm local time
- Place
- Dekalb, Illinois · De Kalb Taylor Municipal Airpo · map
- Type
- Accident
- Injuries
- 1 person was seriously injured.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built T-51
- Registration
- N512JA · registry record · serial 39
- Damage
- Substantial damage
- Flight
- Flight test · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The experimental amateur-built airplane experienced a total loss of engine power during a phase one test flight. The pilot performed a forced landing on a field where airplane nosed-over due to the rough condition of the field that precluded a normal landing rollout. Before the phase 1 test flight, the pilot had returned the engine to the kit manufacturer for repair due to leaking engine coolant. Postaccident examination of the engine revealed catastrophic damage; the engine head bolt had been tighten above the engine manufacturer's torque values, which indicated that the kit manufacturer used excessive torque on the head bolts in an attempt to repair coolant leakage through the engine head. The postaccident examination showed that the engine was assembled with cast and not forged pistons, which should be used in high performance applications. The bending and thread damage on the intact connecting rod bolt for the forward right cylinder and the mating thread damage in the connecting rod were consistent with the bolt backing out until it sheared the remaining threads. Another bolt that backed out of position was also present on the connecting rod in the middle right position. Measurements of cylinder wall carbon lines showed a variance in size, which may have been due to hydraulic lock related bending of the connecting rods.
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
- Aircraft maintenance event during prior to flight
- Powerplant sys/comp malf/fail during enroute (climb to cruise) defining event
- Loss of engine power (total) during enroute (climb to cruise)
- Loss of engine power (total) during emergency descent
- Off-field or emergency landing during landing (flare/touchdown)
- Nose over/nose down during landing (flare/touchdown)
- Collision with terrain or object (not controlled flight into terrain) during landing (flare/touchdown)
The NTSB's findings
- cause Aircraft › Aircraft power plant › Engine (reciprocating) › Recip eng cyl section › Incorrect service/maintenance
- cause Personnel issues › Task performance › Maintenance › Scheduled/routine maintenance › Maintenance personnel
- Environmental issues › Physical environment › Terrain › Rough terrain › Effect on equipment
Pilot
- Certificate: airline transport pilot, flight instructor, commercial pilot, flight engineer
- Ratings: multi-engine land; single-engine land; single-engine sea; instructor: airplane single-engine; instructor: instrument airplane; instrument: airplane
- Flight time: 13,230 hours in all; 7 in this make and model; 9 in the last 90 days; 5 in the last 30 days; 13,230 as pilot in command; 336 on instruments
- Last flight review: July 15, 2011
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: frt
- Injury: serious injuries
The aircraft
- Airframe total time: 5 hours
- Last inspection: condition inspection, November 28, 2012
- Maximum gross weight: 1,650 lb
- Seats: 2
- Landing gear: retractable
- Engine: Honda J35 A6 (piston); 25 hours total
The flight
- Departed from: DKB Dekalb IL at 9:45 pm
- Destination: DKB Dekalb IL
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 190° at 3 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 27°F (-3°C), dew point 23°F (-5°C)
- Altimeter: 29.98 inHg
- Observation at 9:35 pm from DKB, 1 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.
Other NTSB records under N512JA 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.