Beech 99 accident near Mosinee, Wisconsin, December 23, 2006
On December 23, 2006 at about 1:00 am local time, a Beech 99, registered N799CZ, was substantially damaged in an accident near Mosinee, Wisconsin. It was a positioning flight under general aviation rules (Part 91). No one was hurt; 1 person was on board or involved. The weather was instrument conditions (cloud, fog or low visibility).
The NTSB's probable cause their words, unchanged
The pilot encountering the unsuitable terrain during the landing. Factors were the dark night and the snowbank.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- December 23, 2006 · about 1:00 am local time
- Place
- Mosinee, Wisconsin · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- instrument conditions (cloud, fog or low visibility)
- Aircraft
- Beech 99 · all 99s on the register
- Registration
- N799CZ · registry record · serial U-68
- Damage
- Substantial damage
- Flight
- Positioning flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The airplane, on a non-scheduled domestic cargo positioning flight, sustained substantial damage on impact with a snowbank and terrain during landing. The pilot, in part, stated, "I executed a routine [instrument landing system] approach ... during moderate to heavy snowfall at Central Wisconsin Airport. The runway conditions were reported as poor and it was snow covered. A crosswind existed as well as some wind shear as noted during the approach. Central Wisconsin Tower also advised me of a snow berm that remained on the west side of RWY 35 because it was not plowed to the full width of the runway. After I got a visual on the runway lights, I judged the runway centerlines by the runway lights and my position in between them. After the main wheels touched, I let the nose wheel down and I could see via the landing lights that I was close to the berm on my side and I gradually pushed right rudder pedal to steer away from the snow berm. I did not apply any braking action to avoid skidding and I was above 60 kts and had plenty of runway remaining to bleed off speed. Just as I positioned the power levers in the beta range, the left outer main landing gear tire began to make contact with the edge of the remaining snow berm left by the plows. The aircraft then began to yaw to the left and I applied more right rudder to compensate, but to no avail. The nose wheel hit the snow berm and broke off sending the aircraft sailing over the berm. The main landing gear wheels collapsed completely and the aircraft slid to a stop approximately 200 ft. west of RWY 35 off of the runway."
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: commercial pilot
- Ratings: multi-engine land; single-engine land; instrument: airplane
- Flight time: 3,500 hours in all; 230 in this make and model; 110 in the last 90 days; 44 in the last 30 days
- Medical certificate: Class 2 (without waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 29,609 hours
- Last inspection: approved inspection programme, December 1, 2006
- Maximum gross weight: 8,023 lb
- Seats: 2
- Landing gear: retractable
- Engine 1: Pratt & Whitney PT6A-28 (turboprop); 0 hours total
- Engine 2: Pratt & Whitney PT6A-28 (turboprop); 0 hours total
The flight
- Departed from: OSH Oshkosh WI
- Destination: CWA Mosinee WI
- Flight plan: IFR
- Runway 35, 6,500 ft by 150 ft
Weather at the time
- Light: night, dark
- Wind: from 280° at 5 knots
- Visibility: 1 statute miles
- Sky: overcast at 300 ft
- Temperature: 32°F (0°C), dew point 32°F (0°C)
- Altimeter: 29.56 inHg
- Observation at 6:45 pm from CWA
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.
Other NTSB records under N799CZ the same tail number, which may have belonged to a different aircraft at the time
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.