Ercoupe 415 D accident near Monmouth, Illinois, June 24, 2018
On June 24, 2018 at about 4:15 pm local time, a 1946 Ercoupe 415 D, registered N94070, was destroyed in an accident during maneuvering near Monmouth, Illinois (Monmouth Muni airport). 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
A loss of engine power for reasons that could not be determined based on the available information.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- June 24, 2018 · about 4:15 pm local time
- Place
- Monmouth, Illinois · Monmouth Muni · map
- Type
- Accident
- Injuries
- 2 people were killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Ercoupe 415 D, built 1946 · all 415 Ds on the register
- Registration
- N94070 · no longer on the register · serial 1393
- Damage
- Destroyed
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The private pilot and a pilot-rated passenger departed on a local flight to complete touch-and-go landings at a nearby airport. The airplane was in the traffic pattern when witnesses reported that the airplane flew very low over their house and that the engine was "sputtering and backfiring." The airplane flew about 30 ft above them, made a steep left bank toward the airport, then impacted the ground in a wooded area. A postimpact fire consumed a majority of the airplane; the propeller exhibited signatures consistent with a lack of engine power at impact.Although impact and thermal damage precluded a detailed examination of the engine and fuel system, examination did not reveal any evidence of preimpact mechanical malfunction or abnormalities that would have led to a loss of engine power. The investigation was unable to determine the cause of the loss of engine power based on the available information.
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 maneuvering defining event
- Collision with terrain or object (not controlled flight into terrain) during maneuvering
The NTSB's findings
- cause Not determined › Not determined › (general) › (general) › Unknown/Not determined
Pilot
- Certificate: private
- Ratings: single-engine land
- Flight time: 361.5 hours in all
- Last flight review: August 13, 2016
- Medical certificate: Class 3 (with waivers/limitations)
- Seat: left
- Injury: fatal
Pilot-Rated Passenger
- Certificate: private
- Ratings: single-engine land
- Flight time: 775 hours in all
- Medical certificate: Class 3 (with waivers/limitations)
- Seat: rgt
- Injury: fatal
The aircraft
- Airframe total time: 4,135.4 hours
- Last inspection: annual inspection, October 19, 2017
- Maximum gross weight: 1,400 lb
- Seats: 2
- Landing gear: fixed
- Engine: Continental Motors O-200A (piston); 763 hours total
- Fire on the ground
The flight
- Departed from: C66 Monmouth IL at 3:49 pm
- Destination: C66 Monmouth IL
- Flight plan: none
- Runway 21, 2,899 ft by 60 ft
- A second pilot was aboard
Weather at the time
- Light: daylight
- Visibility: 10 statute miles
- Sky: scat at 2,800 ft
- Temperature: 79°F (26°C), dew point 64°F (18°C)
- Altimeter: 29.95 inHg
- Observation at 4:15 pm from GBG, 9 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
11 documents, released by the NTSB on July 26, 2019. 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 | Witness Statement Summary | PDF, 1 page | View Download |
| 2 | Witness Statement | PDF, 2 pages | View Download |
| 3 | Coroner's Report Excerpt | PDF, 1 page | View Download |
| 4 | radar Tabular Data | data file | Download |
| 5 | Pilot's Logbook | PDF, 19 pages | View Download |
| 6 | Maintenance Records | PDF, 10 pages | View Download |
| 7 | NTSB Engine Factual Report | PDF, 10 pages | View Download |
| 8 | Photos | PDF, 3 pages | View Download |
| 9 | Fuel Receipt | PDF, 1 page | View Download |
| 10 | Toxicological Report - Pilot | PDF, 2 pages | View Download |
| 11 | Toxicological Report - Passenger | 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.