Aerospatiale ATR-42 incident near Mosinee, Wisconsin, December 22, 1988
On December 22, 1988 at about 10:29 pm local time, a Aerospatiale ATR-42, registered N427MQ, was involved in an incident near Mosinee, Wisconsin (Central Wisconsin airport). It was a flight of an unrecorded kind under scheduled airline rules (Part 121). No one was hurt; 37 people were on board or involved. The weather was instrument conditions (cloud, fog or low visibility).
The NTSB's probable cause their words, unchanged
STALL INDUCED BY THE ACCRETION OF MODERATE TO SEVERE CLEAR ICING.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- December 22, 1988 · about 10:29 pm local time
- Place
- Mosinee, Wisconsin · Central Wisconsin · map
- Type
- Incident
- Injuries
- No one was hurt; 37 people were on board or involved.
- Weather
- instrument conditions (cloud, fog or low visibility)
- Aircraft
- Aerospatiale ATR-42 ATR 42
- Registration
- N427MQ · no longer on the register · serial 0091
- Damage
- Not recorded
- Flight
- Flight of an unrecorded kind · scheduled airline rules (Part 121)
The NTSB's narrative final · quoted from the NTSB record
A MISSED APPROACH WAS EXECUTED ON THE FIRST APPROACH, AND THE CREW ELECTED TO FLY THE COMPLETE PROCEDURE TURN FOR THE ILS AT THE CENTRAL WISCONSIN AIRPORT. BOTH THE FIRST AND SECOND APPROACHS WERE FLOWN AT 3000 FEET MSL IN IMC CONDITIONS WITH MODERATE TO HEAVY RAIN. A TEMPERATURE INVERSION EXISTED FROM 5000 FEET TO 3000 FEET MSL WHICH CREATED CONDITIONS CONDUCIVE TO MODERATE TO SEVERE CLEAR ICING. THE AIRCRAFT WAS IN THESE CONDITIONS FOR 11.8 MINUTES. APPROXIMATELY ONE-HALF WAY THROUGH THE PROCEDURE TURN, WHICH WAS FLOWN WITH THE AUTOPILOT ON, THE CAPTAIN REDUCED POWER TO SLOW FOR GEAR EXTENSION. AT 157 KNOTS CLEAN CONFIGURATION THE AIRCRAFT STALLED AND ROLLED 80 DEGREES TO THE LEFT AND 60 DEGREES TO THE RIGHT. THE CREW APPLIED FULL POWER AND EXECUTED STALL RECOVERY PROCEDURES. THE AIRCRAFT WAS RECOVERED WITH AN ALTITUDE LOSS OF 600 FEET. THE CREW DID NOT PERCEIVE ANY ICE ACCRETION, AND THE AIRFRAME DEICE WAS NOT ON UNTIL AFTER THE STALL. THE THIRD APPROACH WAS UNEVENTFUL.
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, commercial pilot
- Ratings: multi-engine land; single-engine land; instrument: airplane
- Flight time: 8,614 hours in all; 565 in this make and model; 113 in the last 90 days; 42 in the last 30 days
- Medical certificate: Class 1 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 1,819 hours
- Last inspection: continuous airworthiness programme
- Maximum gross weight: 36,825 lb
- Seats: 50
- Landing gear: retractable
- Engine: P&W PW-120 (turboprop); 0 hours total
- Operator: Simmons Airlines
The flight
- Departed from: ORD Chicago IL at 9:25 pm
- Flight plan: IFR
- Runway 8, 7,645 ft by 150 ft
- A second pilot was aboard
Weather at the time
- Light: night, dark
- Wind: from 130° at 15 knots, gusting 20
- Visibility: 1 statute miles
- Sky: overcast at 4,000 ft
- Temperature: 30°F (-1°C), dew point 0°F (-18°C)
- Altimeter: 29.00 inHg
- Observation at 10:20 pm from CWA, 10 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 3 | |||
| Passengers | 34 |
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.