Aeromedical Services Intl Mitsubishi MU-2B-60 accident
Mitsubishi MU-2B-60 · Accident: total loss of engine power (mechanical failure) during initial climb
From Rapid City Regional Airport (RAP) to Winnipeg / James Armstrong Richardson International Airport (CYWG)
Event
- NTSB case
- DEN90FA055
- 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
- 1 · 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
- Charter & commuter
- 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
Mitsubishi MU-2B-60
- 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
- N64MD
- Operator
- Aeromedical Services Intl
- Onboard fatalities
- Unknown
- Route
- From Rapid City Regional Airport (RAP)To Winnipeg / James Armstrong Richardson International Airport (CYWG), MANITOBA,CANADA
- 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 135: Air Taxi & Commuter
- 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
- Initial climb
- 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
- Total loss of engine power (mechanical 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
- Pilot in command › Aircraft control, not maintained
- Pilot in command › Airspeed(vmc), not maintained
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
WITNESSES RPRTD THAT SHORTLY AFTER LIFT-OFF, THE ACFT ENTERED AN UNUSUALLY STEEP, NOSE HIGH ATTITUDE, WHILE STILL AT LOW AIRSPEED. ONE WITNESS (AN ATP PLT) RPRTD THE ACFT ATTAINED AN ALT OF APRX 75 TO 100 FT AND APPEARED TO SLOW DOWN AND ENTER A VMC ROLL, THEN IT CRASHED. IMPACT OCCURRED IN AN INVERTED, NOSE DOWN ATTITUDE, LEFT OF THE RWY. AN INVESTIGATION REVEALED THAT A COUPLING SHAFT (PN 865888-3) HAD FAILED IN THE LEFT ENG & THE LEFT PROP HAD FEATHERED. A METALLURICAL EXAM OF THE COUPLING SHOWED EVIDENCE OF FATIGUE.
Probable cause
FAILURE OF THE PILOT TO MAINTAIN ADEQUATE AIRSPEED (VMC), WHICH RESULTED IN A LOSS OF AIRCRAFT CONTROL. A FACTOR RELATED TO THE ACCIDENT WAS: FATIGUE FAILURE OF A COUPLING SHAFT IN THE #1 ENGINE, WHICH RESULTED IN LOSS OF POWER IN THAT ENGINE.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record DEN90FA055
- Event ID
- 20001212X22539
- Case number
- DEN90FA055
- 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: 5f56658fb284e8487638e6c9453916641f7fcaed1d9c60cab814d009580cdecf; retrieved 2026-09-18T14:06:53.685Z.