Simmons Airlines Aerospatiale ATR-42 incident
Aerospatiale ATR-42 · Incident: in flight encounter with weather on approach
From Chicago O'Hare International Airport (ORD) to an unrecorded destination
Event
- NTSB case
- CHI89IA034
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Incident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- 0
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- Airline
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Instrument Meteorological Cond
Aerospatiale ATR-42
- Aircraft type
- Aerospatiale ATR-42
- Category
- Airplane
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N427MQ
- Operator
- Simmons Airlines
- Onboard fatalities
- Unknown
- Route
- From Chicago O'Hare International Airport (ORD), Chicago, ILTo not recorded
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 121: Air Carrier
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Approach · IFR missed approach
- First occurrenceThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- In flight encounter with weather
- Also codedOther events the NTSB coded in the sequence, such as a wire strike after a loss of power. Flight Findings uses them for its kinds of event. Glossary
- Stall
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- None
Cause areas
- Pilot in command › Anti-ice/deice system, not used
- Pilot in command › Stall, encountered
- Wing › Ice
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
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.
Probable cause
STALL INDUCED BY THE ACCRETION OF MODERATE TO SEVERE CLEAR ICING.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CHI89IA034
- Event ID
- 20001213X27394
- Case number
- CHI89IA034
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status, damage. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: c9691b31f41fde78fe86686a1be09a337ef494ab88c204af7d76e4f9ca87d6fc; retrieved 2026-09-18T19:15:56.303Z.