Cessna R172K accident near Lakewood, Wisconsin, June 13, 2007
On June 13, 2007 at about 2:03 pm local time, a Cessna R172K, registered N736MV, was substantially damaged in an accident near Lakewood, Wisconsin (Lakewood Airpark airport). It was a personal flight under general aviation rules (Part 91). 1 person had minor injuries; 2 others were unhurt. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The amphibian nose wheel strut assembly separated due to an overload fracture as a result of the manufacturer's inadequate design.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- June 13, 2007 · about 2:03 pm local time
- Place
- Lakewood, Wisconsin · Lakewood Airpark
- Type
- Accident
- Injuries
- 1 person had minor injuries; 2 others were unhurt.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna R172K · all R172Ks on the register
- Registration
- N736MV · registry record · serial R1722642
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot reported that the right nose wheel separated from the float approximately 210 feet from where the airplane started the takeoff roll, and about 35 feet later, the left nose wheel separated from the float. After the left nose wheel separated, the left nose wheel strut dug into the turf causing the aircraft to nose over. The inspection of the airplane revealed that the nose wheel struts had separated from the castoring assemblies. The left and right nose wheel struts and castoring assemblies were sent to the National Transportation Safety Board's (NTSB) Materials Laboratory for a metallurgical examination. The visual examination of the parts showed that the castoring nose wheels from both floats had fractured at the bearing boss welds to the strut arms. Both strut arms were bent upward. The right arm was bent about 30 degrees and the left was bent about 5 degrees. The strut fractures were located through the fusion zones of the strut to bearing boss welds with some tearing of the boss material at the upper edges of the welds. Microscopic inspection of the fractures on both struts revealed matte gray textured fracture surfaces typical of overstress fractures. Deformation and rearward displacement of the boss material adjacent to the upper edge tears and fracture regions, along with the smearing contact of the lower fracture areas, were consistent with bending overstress forces on the weld joint. On August 8, 2007, Baumann Floats LLC issued Service Bulletin No. 001. The reason for the issuance of the service bulletin was "to improve the service and reliability of the nose gear assembly." The service bulletin modified the G-129 nose gear tube assembly. Compliance with the service bulletin was considered mandatory by the manufacturer upon receipt of the service bulletin, and specifically prior to operating off grass or soft field areas.
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: airline transport pilot
- Ratings: multi-engine land; single-engine land; single-engine sea; instrument: airplane
- Flight time: 24,000 hours in all; 200 in this make and model
- Last flight review: July 1, 2005
- Medical certificate: Class 3 (with waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 2,300 hours
- Last inspection: annual inspection, June 1, 2007
- Maximum gross weight: 2,550 lb
- Seats: 4
- Landing gear: retractable
- Engine: Continental O-360 (piston); 0 hours total
The flight
- Departed from: 4WN3 Lakewood WI at 3:00 pm
- Flight plan: none
- Runway 09, 2,500 ft by 150 ft
Weather at the time
- Light: daylight
- Wind: from 160° at 5 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 75°F (24°C), dew point 52°F (11°C)
- Altimeter: 30.19 inHg
- Observation at 2:55 pm from KAIG, 26 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 1 | 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.