Amateur-built 1600 accident near Lebanon, Tennessee, January 7, 2016
On January 7, 2016 at about 9:40 pm local time, a 2014 amateur-built 1600, registered N508AH, was substantially damaged in an accident during initial climb near Lebanon, Tennessee (Lebanon Muni airport). It was a personal flight under general aviation rules (Part 91). 1 person was killed. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
A failure of the front cylinder piston due to the pilot's improper maintenance, which resulted in a total loss of engine power after takeoff. Contributing to the accident was the pilot's decision to return to the runway at low altitude following the loss of engine power, and his failure to maintain adequate airspeed during the turn, which resulted in the airplane exceeding its critical angle of attack and experiencing an aerodynamic stall.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- January 7, 2016 · about 9:40 pm local time
- Place
- Lebanon, Tennessee · Lebanon Muni · map
- Type
- Accident
- Injuries
- 1 person was killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built 1600, built 2014
- Registration
- N508AH · 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
The private pilot conducted a 20-minute local flight in the experimental, amateur-built airplane after installing a new ignition coil on the two-stroke, two-cylinder engine. He then returned to the departure airport, where he landed the airplane, back-taxied on the runway, and initiated a second takeoff. Witnesses reported that, shortly after takeoff, the airplane experienced a total loss of engine power. The airplane entered a left turn back toward the runway, then subsequently turned "sharply" left and descended to ground contact. Examination of the airframe revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. Examination of the engine revealed that the front spark plug was burnt white, consistent with exposure to high temperatures or an excessively lean carburetor calibration. Although both front and aft carburetor adaptors exhibited degradation, the front cylinder adaptor exhibited significantly more damage and cracking compared to that of the aft cylinder. This likely resulted in additional air being ingested by the front carburetor, which subsequently resulted in a leaner fuel/air mixture in that cylinder. In addition, the front cylinder piston exhibited a hole about 1 centimeter in diameter, consistent with detonation/preignition. Records located in the pilot's hangar indicated that the pilot was servicing the engine with a fuel/oil ratio of 40:1, rather than the manufacturer-recommended ratio of 50:1. It is likely that the use of an improper fuel/oil ratio resulted in carbon deposits in the front cylinder. Combined with the effects of the lean fuel/air mixture as a result of the degraded carburetor adaptors, the engine was susceptible to the development of detonation and/or preignition, which subsequently resulted in the development of a hole in the front cylinder piston head. As a result, the engine experienced a total loss of power, to which the pilot responded by attempting to turn back to the airport at low altitude. During the turn, the pilot allowed the airplane's airspeed to decay and exceeded its critical angle of attack, which resulted in an aerodynamic stall and collision with terrain.
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
- Loss of engine power (total) during initial climb defining event
- Abrupt maneuver during emergency descent
- Aerodynamic stall/spin during emergency descent
- Collision with terrain or object (not controlled flight into terrain) during uncontrolled descent
The NTSB's findings
- cause Aircraft › Aircraft power plant › Engine (reciprocating) › Recip eng cyl section › Failure
- cause Personnel issues › Task performance › Maintenance › Scheduled/routine maintenance › Pilot
- factor Personnel issues › Action/decision › Info processing/decision › Decision making/judgment › Pilot
- factor Personnel issues › Task performance › Use of equip/info › Aircraft control › Pilot
- factor Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Airspeed › Not attained/maintained
- factor Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Angle of attack › Not attained/maintained
Pilot
- Certificate: private
- Ratings: single-engine land
- Flight time: 259.3 hours in all; 8.8 in this make and model; 26.1 in the last 90 days; 7 in the last 30 days; 211.1 as pilot in command
- Last flight review: May 27, 2014
- Medical certificate: Class 3 (without waivers/limitations)
- Seat: sngl
- Injury: fatal
The aircraft
- Airframe total time: 14 hours
- Last inspection: condition inspection, October 7, 2015; 12 hours since
- Maximum gross weight: 700 lb
- Seats: 1
- Landing gear: fixed
- Engine: Rotax 532 (piston); 0 hours total
The flight
- Departed from: M54 Lebanon TN at 9:38 pm
- Destination: M54 Lebanon TN
- Flight plan: none
- Runway 04, 1,801 ft by 150 ft
Weather at the time
- Light: daylight
- Wind: from 120° at 4 knots
- Visibility: 10 statute miles
- Sky: broken clouds at 3,500 ft
- Temperature: 55°F (13°C), dew point 46°F (8°C)
- Altimeter: 30.02 inHg
- Observation at 9:53 pm from MQY, 14 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.