Dayton-Wright DH-4 accident near Bowling Green, Kentucky, May 2, 2020
On May 2, 2020 at about 12:00 pm local time, a 1918 Dayton-Wright DH-4, registered N32517, was substantially damaged in an accident during takeoff near Bowling Green, Kentucky (Bowling Green-Warren County Rg 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
A primary control (aileron) system anomaly that progressively worsened during a test flight that resulted in a loss of control. The reason for the anomaly was not determined due to impact damage.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- May 2, 2020 · about 12:00 pm local time
- Place
- Bowling Green, Kentucky · Bowling Green-Warren County Rg · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Dayton-Wright DH-4, built 1918
- Registration
- N32517 · no longer on the register · serial 12459
- Damage
- Substantial damage
- Flight
- Flight test · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot reported that, during the first flight test of the antique airplane, which was in the process of being restored, he had difficulty controlling the airplane in the roll axis. After takeoff, he noticed that the airplane required some right aileron to keep the wings level. After turning crosswind, the problem worsened, and required that he apply more pressure to the control stick (in the right aileron direction). As he turned downwind, he used nearly full right aileron to maintain control, and the force on the control stick was so high that he was unable to hold it with one hand. When he removed his left hand from the control stick to adjust the throttle, the airplane would roll toward the left. As the airplane approached the base leg, the pilot was unable to keep the wings level; the airplane entered a slip and he was unable to prevent the airplane from turning left. The airplane descended, touched down in the grass to the right of the runway, and came to rest nose down. Examination of the airplane revealed that the aileron control system was continuous. However, due to the airplane damage, the rigging of the aileron system could not be evaluated. The airplane sustained substantial damage to the forward fuselage, lower wing, and horizontal stabilizer.
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
- Flight control sys malf/fail during takeoff defining event
The NTSB's findings
- cause Aircraft › Aircraft systems › Flight control system › Aileron control system › Malfunction
- cause Not determined › Not determined › (general) › (general) › Unknown/Not determined
- Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Lateral/bank control › Attain/maintain not possible
Pilot
- Certificate: private
- Ratings: single-engine land; instrument: airplane
- Flight time: 946 hours in all; 309 in this make and model; 16 in the last 90 days; 3 in the last 30 days; 946 as pilot in command
- Last flight review: January 10, 2019
- Medical certificate: Class 3 (with waivers/limitations)
- Seat: ctr
- Injury: no injuries
The aircraft
- Airframe total time: 5 hours
- Last inspection: annual inspection, January 25, 2020; 5 hours since
- Maximum gross weight: 4,297 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lincoln Liberty V12 (piston); 5 hours total
- Operator: Saving Liberty Dh4 Llc
The flight
- Departed from: BWG Bowling Green KY at 11:52 am
- Destination: BWG Bowling Green KY
- Flight plan: none
- Runway 03, 6,501 ft by 150 ft
Weather at the time
- Light: daylight
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 55°F (13°C), dew point 52°F (11°C)
- Altimeter: 30.12 inHg
- Observation at 11:53 am from BWG
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
3 documents, released by the NTSB on June 26, 2020. View them here, or download them; the NTSB redacts some personal details before release, and this site shows the NTSB's own titles rather than its file names.
| # | Document | What it is | |
|---|---|---|---|
| 1 | Pilot/operator Aircraft Accident Report, NTSB Form 6120.1 | PDF, 11 pages | View Download |
| 2 | Memorandum for Record - FAA Inspector | PDF, 1 page | View Download |
| 3 | Photos | PDF, 3 pages | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
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.