Amateur-built Mariner-MF Boat accident near Eagle River, Wisconsin, September 21, 2004
On September 21, 2004 at about 1:40 pm local time, a amateur-built Mariner-MF Boat, registered N744PK, was substantially damaged in an accident near Eagle River, Wisconsin (Eagle River Union airport). It was a flight test under general aviation rules (Part 91). 1 person was seriously injured. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot's inability to maintain control of the aircraft during flight for undetermined reasons.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- September 21, 2004 · about 1:40 pm local time
- Place
- Eagle River, Wisconsin · Eagle River Union · map
- Type
- Accident
- Injuries
- 1 person was seriously injured.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built Mariner-MF Boat
- Registration
- N744PK · no longer on the register · serial 60
- Damage
- Substantial damage
- Flight
- Flight test · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The experimental amateur-built airplane was substantially damaged and the pilot seriously injured when the left wing tip struck the ground during landing causing the aircraft to spin around and crash. The pilot stated that this was the first flight of the airplane since it had been rebuilt. He reported that ground taxi testing was conducted and did not reveal any problems. According to the pilot, after takeoff the airplane was "swaying side to side." He decided to return for landing and entered a left-hand traffic pattern. The pilot reportedly reduced engine power on base leg and began a descent for landing. He stated that the nose was "pitching and yaw[ing] back and forth." The wings did not want to stay level, according to the pilot. He noted the final approach was into the wind with some "side gust." On final approach, about 8 feet above the ground, wind conditions caused the left wing to hit the ground and the airplane spun around. The airplane came to rest about 100 feet southeast of the runway. The airport manager witnessed the accident. He reported that during takeoff the airplane porpoised twice before it started climbing. He noticed the airplane again on what appeared to be a downwind traffic pattern leg for runway 13. He noted that "the aircraft looked like it was having control problems and could not stay in coordinated flight. It looked like every time he attempted to make a left turn the airplane would skid to the right." The witness reported that during the landing the aircraft was "very uncoordinated" and started to porpoise 4 or 5 times above the runway. The witness stated the engine power accelerated and then the left wing tip struck the ground and the aircraft crashed. A post-accident examination of the wreckage revealed no defects associated with a pre-impact failure. Flight control continuity was confirmed.
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
Pilot
- Certificate: private
- Ratings: single-engine land
- Flight time: 169 hours in all; 169 as pilot in command
- Last flight review: January 1, 1992
- Medical certificate: Class 3 (valid medical--no waivers/lim.)
- Seat: frt
- Injury: serious injuries
The aircraft
- Airframe total time: 250 hours
- Last inspection: condition inspection, August 19, 2004; 10 hours since
- Maximum gross weight: 677 lb
- Seats: 2
- Landing gear: fixed
- Engine: Subaru EA81-1986 (piston); 0 hours total
The flight
- Departed from: EGV Eagle River WI at 1:35 pm
- Flight plan: none
- Runway 22, 4,996 ft by 75 ft
Weather at the time
- Light: daylight
- Wind: from 220° at 6 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 57°F (14°C), dew point 48°F (9°C)
- Altimeter: 30.10 inHg
- Observation at 1:35 pm from EGV
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| 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.