CHI02LA044 · Mitsubishi MU-2B-40
Mitsubishi MU-2B-40 · Accident: airframe, component or system failure on approach
From Southwest Michigan Regional Airport (BEH) to Saint Paul Downtown Holman Field (STP)
Event
- NTSB case
- CHI02LA044
- 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
- Accident
- 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
- Unknown
- 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
- General aviation
- 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
Mitsubishi MU-2B-40
- Aircraft type
- Mitsubishi MU-2
- 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
- N9052Y
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Southwest Michigan Regional Airport (BEH), Benton Harbor, MITo Saint Paul Downtown Holman Field (STP), Saint Paul, MN
- 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 91: General Aviation
- 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
- Airframe, component or system failure
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Autopilot/flight director, amplifier and computer › Arcing
- Pilot in command › Missed approach, not performed
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The airplane sustained substantial damage on impact with the runway during a hard landing following a coupled autopilot approach. The pilot and three passengers were uninjured. Instrument meteorological conditions prevailed. The pilot reported, "I was using the autopilot to fly the ILS localized timed approach. I was looking for the runway and watching the time. The autopilot inadvertently disengaged, turning the airplane to the left. I righted the airplane just before touchdown. It landed on the mains with the nose slightly high. It came down, and the front wheel and strut broke." During the next flight, a ferry flight for repairs, the accident pilot reported that he engaged the autopilot at 2,500 feet. The pilot reported that when the autopilot was engaged, the airplane pitched down and turned sharply to the right. The pilot reported using opposing control inputs and differential engine power to maintain airplane control. The pilot performed a no flap landing at an en route airport with a 2,497-foot long runway. An examination of the airplane revealed that when the autopilot computer was moved in its shock mount the yoke moved "violently right in roll axis and forward in pitch axis." The MU-2 airplane flight manual's emergency procedures stated, "In case of emergency, the autopilot can be overpowered manually to correct the attitude, but the autopilot must immediately be disengaged. If the autopilot remains engaged, the autopilot will trim the airplane to oppose the pilot's actions. This could result in a severely out of trim condition." The manual stated, "The autopilot can also be disengaged by any of the following methods, "1. Operate trim switch UP or DOWN, 2. Position inverter switch to OFF momentarily and then return, to original position, 3. Turn off the ELECTRIC MASTER SWITCH." The pilot reported 11 hour hours of pilot in command time in the accident airplane make and model.
Probable cause
The autopilot's computer connections arcing and reported disconnection during the localizer approach and the pilot not performing a go around prior to the hard landing. A factor was the pilots lack of total experience in the accident airplane's make and model.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CHI02LA044
- Event ID
- 20011204X02344
- Case number
- CHI02LA044
- 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. 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: 6fc6d92c113e37a3c5d813636fb3402e77abf186e278a627f9f33ab69155370d; retrieved 2026-09-22T11:18:29.895Z.