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NTSB Report
February 9, 1990 · Mitsubishi MU-2B-60 · N64MD
Rapid City, SD
Overview
Report Status
Probable Cause
Event Type
Accident
Date
February 9, 1990
Injury Outcomes
4 injuries (1 fatality, 1 serious injury, 2 minor injuries)
Location
Rapid City, SD
Aircraft
Mitsubishi MU-2B-60
Tail Number
N64MD
Operator
Aeromedical Services Intl
Injuries
Fatal
Aircraft Damage
Substantial
NTSB Number
DEN90FA055
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.
NTSB 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.
Full 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.
Flight
Event TypeAccident
Event Time11:14 MST
Nearest AirportRapid City Regional (0nm N)
Runway14
Runway Length8701 ft
Runway Width150 ft
Flight Plan FiledVfif
Aircraft FireGrd
Aircraft ExplosionNo
Aircraft
AircraftMitsubishi MU-2B-60
Tail NumberN64MD
Aircraft CategoryAir
DamageSubstantial
OperatorAeromedical Services Intl
Operating RulePart 135
Engines2
Engine TypeTurboprop
Engine DetailsGarrett · TPE-331-10 · Turboprop · 715
Seats7
People & Injuries
Injury Summary4 injuries (1 fatality, 1 serious injury, 2 minor injuries)
Fatal1
Serious1
Minor2
Uninjured0
Total4
Crew 1Age 46 · First Class
Conditions
ConditionsVMC
LightDaylight
Wind170° @ 14 kt
Visibility35 sm
CeilingBroken clouds 7000 ft
Temperature / Dew Point32 C / 18 C
Altimeter29.00 inHg
Observation Time18:16
Weather SourceWFAC