CHI90IA106 · Nihon YS-11A-600F YS-11A-600
Nihon YS-11A-600F YS-11A-600 · Incident: uncontrolled altitude deviation on approach
From Willow Run Airport (YIP) to an unrecorded destination
Event
- NTSB case
- CHI90IA106
- 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
- Visual Meteorological Cond
Nihon YS-11A-600F YS-11A-600
- Aircraft type
- Nihon YS-11
- 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
- N112MP
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Willow Run Airport (YIP), Detroit, MITo 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 final 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
- Uncontrolled altitude deviation
- 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
No findings designated as a cause are recorded in the NTSB data yet.
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
THE TRANSPORT CATEGORY AIRCRAFT WAS RETURNING TO THE HOME BASE EMPTY (BALLAST ONLY). WEATHER CONDITIONS EXISTED WHICH WERE CONDUCIVE TO AIRFRAME ICING. ON FINAL APPROACH, WHEN LANDING FLAPS WERE SELECTED, THE AIRCRAFT PITCHED NOSE DOWN ACCOMPANIED BY BUFFETING OF THE AIRFRAME. THE CAPTAIN TOOK CONTROL (FIRST OFFICER HAD BEEN FLYING) AND ADDED FULL POWER. THE FIRST OFFICER SELECTED 15 DEGREES FLAP. THE AIRCRAFT RECOVERED, BUT CONTINUED TO EXHIBIT BUFFETING. THE AIRCRAFT DIVERTED TO AN AIRPORT WITH A LONGER RUNWAY AND A SUCCESSFUL LANDING WAS ACCOMPLISHED. SUBSEQUENT INVESTIGATION REVEALED SUBSTANTIAL ICE ACCUMULATION OUTSIDE THE BOOTED AREA ON THE HORIZONTAL TAIL.
Probable cause
AN UNDETECTED ACCUMULATION OF ICE ON THE HORIZONTAL STABILIZER. RELATING FACTORS WERE THE MANUFACTURER'S LACK OF INFORMATION AND AIRCRAFT MANUALS RELATIVE TO THE UNDERSTANDING OF, AND APPROPRIATE PROCEDURES TO PREVENT THE LOSS OF CONTROL.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CHI90IA106
- Event ID
- 20001212X22877
- Case number
- CHI90IA106
- 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: 957e46f68539e95107b8739a07ac35516e0068659eb623798db5759f5aeb9b93; retrieved 2026-09-18T19:03:30.631Z.