Amateur-built IV accident near Perry, Florida, November 17, 2023
On November 17, 2023 at about 10:08 pm local time, a 1999 amateur-built IV, registered N37MB, was substantially damaged in an accident during enroute (descent) near Perry, Florida. It was a personal flight under general aviation rules (Part 91). 1 person had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
A rapid throttle advancement after a period of idling, which resulted in a flooded engine and total loss of engine power.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- November 17, 2023 · about 10:08 pm local time
- Place
- Perry, Florida · map
- Type
- Accident
- Injuries
- 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built IV P, built 1999
- Registration
- N37MB · registry record · serial LIV-362
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot reported a loss of engine power after descending from 11,500 ft mean sea level (msl) and leveling off under a cloud layer at 2,000 ft msl. The pilot switched fuel tanks and enrichened the mixture; however, he was unable to restore engine power and elected to execute a forced landing during which he impacted trees. Postaccident examination of the airframe and fuel-injected engine revealed no anomalies that would have precluded normal operation. The engine subsequently started without hesitation during a test cell run at the manufacturer’s facility. After running at idle for 5 minutes, the engine was run for 5 minutes at various rpm settings. The engine test run revealed that the fuel system was mal-adjusted and set too lean, and the manifold pressure was about 2 inches of mercury lower than that required to produce rated power. This could have been due to an observed leak of the turbocharger exhaust or the sonic venturis which were open to the atmosphere for the engine test. Following these static engine runs, the engine was brought to idle and then the throttle was rapidly advanced. When the throttle was advanced quickly, the engine ran very rich with black exhaust smoke, and then would falter. If the throttle was not immediately retarded, the engine lost power completely. If the engine was immediately brought back to idle after it faltered upon rapid throttle advancement, the engine regained power. This was consistent with the engine flooding with rapid throttle advancement after a period of idling. Given that no anomalies were noted in the examination and that the engine repeatedly stopped producing power after rapid throttle advancement after a period of idling in the test cell, it is possible that the speed with which the pilot advanced the throttle after leveling from the descent was too quick. The engine likely then would have flooded with fuel and stopped producing power, similar to the behavior observed during the postaccident test run.
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 enroute (descent) defining event
- Off-field or emergency landing during enroute (descent)
The NTSB's findings
- Aircraft › Aircraft power plant › Engine fuel and control › (general) › Not specified
Pilot
- Certificate: private
- Ratings: single-engine land; rotorcraft: helicopter
- Flight time: 311 hours in all; 64 in this make and model; 25 in the last 90 days; 16 in the last 30 days; 210 as pilot in command
- Medical certificate: Class 3 (without waivers/limitations)
- Seat: left
- Injury: minor injuries
The aircraft
- Airframe total time: 1,016.4 hours
- Last inspection: annual inspection, October 1, 2023; 25.1 hours since
- Maximum gross weight: 3,200 lb
- Seats: 4
- Landing gear: retractable
- Engine: Continental TSIO-550-E1B (piston); 1,016 hours total
The flight
- Departed from: CFD Bryan TX at 7:58 pm
- Destination: X39 Tampa FL
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 359° at 6 knots
- Sky: overcast at 2,300 ft
- Temperature: 73°F (23°C), dew point 64°F (18°C)
- Altimeter: 29.83 inHg
- Observation at 5:35 pm from FPY, 8 miles away
Weather report (METAR): METAR KFPY 172235Z AUTO 36006KT 10SM OVC023 23/18 A2983 RMK AO2 T02260183=
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Photographs from the investigation 4 pictures from the NTSB's docket, as the NTSB released them
Photograph 1 – View of inverted airplane from front.
Photograph 2 – View of inverted airplane from right wing.
Photograph 3 – View of inverted airplane from rear.
Photograph 4 – View of inverted airplane from left wing.The NTSB's photographs with the NTSB's captions, at screen size. Open a picture to see it full size or to report one that should not be shown.
Documents from the investigation the NTSB's docket: the evidence folder behind the report
10 documents, released by the NTSB on September 5, 2024. 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 | Pilot Statements | PDF, 3 pages | View Download |
| 3 | Maintenance Log Excerpts | PDF, 4 pages | View Download |
| 4 | Investigative Photographs | PDF, 5 pages · our copy | View Download |
| 5 | Airframe and Engine Examination Summary | PDF, 5 pages | View Download |
| 6 | Manufacturer Engine Test Run Summary | PDF, 7 pages | View Download |
| 7 | Engine Test Run Video 1 | video | View Download |
| 8 | Engine Test Run Video with Engine Quitting with Rapid Throttle Advancement) | video | View Download |
| 9 | Statement of Party Representatives to NTSB Investigation | PDF, 1 page | View Download |
| 10 | Release of Aircraft Wreckage, NTSB Form 6120.15 | PDF, 1 page | 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.