Amateur-built ACRO SPORT II accident near Middletown, Ohio, September 20, 2014
On September 20, 2014 at about 12:57 pm local time, a 1994 amateur-built ACRO SPORT II, registered N94SM, was substantially damaged in an accident during maneuvering (aerobatics) near Middletown, Ohio. It was a personal flight under general aviation rules (Part 91). 2 people were killed. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The failure of the flying pilot to maintain airplane control after an aerodynamic stall/spin occurred during the aerobatic maneuver following a reported intermittent loss of engine power for reasons that could not be determined during postaccident examinations.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- September 20, 2014 · about 12:57 pm local time
- Place
- Middletown, Ohio · map
- Type
- Accident
- Injuries
- 2 people were killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built ACRO SPORT II, built 1994
- Registration
- N94SM · no longer on the register · serial 733
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot and pilot-rated passenger were flying a local flight and performing aerobatic maneuvers in the experimental amateur-built airplane. A witness reported that she heard the airplane approaching and then saw it and noted that it was at a lower altitude than she normally saw aircraft in the area. The airplane then started to pitch nose up into a loop. As the airplane reached the top of the looping maneuver, the sound of the engine stopped, and the airplane then immediately started descending. The airplane then entered a spiral/spin, and the witness lost sight of the airplane behind some trees. She then heard the sound of an engine, consistent with the pilot adding engine power, followed immediately by the sound of impact. The airplane was engulfed in flames upon her arrival. The witness demonstrated what she had seen with a model airplane, and the demonstration was consistent with an attempted loop with a spin out of the top of the maneuver. Witness marks at the accident site revealed that the airplane was producing power at the time of impact. An examination of the engine and flight controls did not reveal any preimpact anomalies that would have precluded operation. A weight and balance calculation showed that the airplane was within its published limits. The airplane likely experienced an aerodynamic stall at the top of the looping maneuver and then entered a spin from which the flying pilot was not able to recover. The investigation could not determine which occupant was manipulating the controls during the flight.
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 (partial) during maneuvering (aerobatics)
- Loss of control in flight during maneuvering (aerobatics) defining event
- Collision with terrain or object (not controlled flight into terrain) during uncontrolled descent
The NTSB's findings
- factor Aircraft › Aircraft power plant › Engine (reciprocating) › (general) › Malfunction
- cause Personnel issues › Task performance › Use of equip/info › Aircraft control › Pilot
- cause Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Airspeed › Not attained/maintained
- cause Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Angle of attack › Not attained/maintained
Pilot
- Certificate: private
- Ratings: single-engine land; instrument: airplane
- Flight time: 1,662 hours in all; 6 in this make and model; 41 in the last 90 days; 12 in the last 30 days
- Last flight review: May 3, 2014
- Medical certificate: Class 3 (without waivers/limitations)
- Seat: frt
- Injury: fatal
Pilot-Rated Passenger
- Certificate: private
- Ratings: single-engine land
- Flight time: 906.5 hours in all; 2 in this make and model; 24.5 in the last 90 days; 2 in the last 30 days
- Last flight review: May 14, 2014
- Medical certificate: Class 3 (without waivers/limitations)
- Seat: rear
- Injury: fatal
The aircraft
- Airframe total time: 596 hours
- Last inspection: condition inspection, August 28, 2014
- Maximum gross weight: 1,682 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming IO-360-A1A (piston); 0 hours total
- Fire on the ground
- Operator: Biplane Crazy, LLC
The flight
- Departed from: HAO Hamilton OH at 12:30 pm
- Destination: HAO Hamilton OH
- Flight plan: none
- A second pilot was aboard
Weather at the time
- Light: daylight
- Visibility: 6 statute miles
- Sky: a few clouds at 4,700 ft
- Temperature: 61°F (16°C), dew point 55°F (13°C)
- Altimeter: 30.10 inHg
- Observation at 12:53 pm from KHAO, 8 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | |||
| Passengers | 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 N94SM 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.