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NTSB Report
May 5, 1993 · Schweizer 269C · N7504D
Grand Forks, ND
Overview
Report Status
Probable Cause
Event Type
Accident
Date
May 5, 1993
Injury Outcomes
1 injury (1 minor injury)
Location
Grand Forks, ND
Aircraft
Schweizer 269C
Tail Number
N7504D
Operator
University of North Dakota
Injuries
Minor
Aircraft Damage
Substantial
NTSB Number
CHI93LA159
THE PILOT WAS PRACTICING LANDINGS WHEN THE ACCIDENT OCCURRED. THE PILOT STATED HE LOWERED THE COLLECTIVE AND CENTERED THE CYCLIC IN ORDER TO STOP A GROUND RUN DURING THE LANDING. THE HELICOPTER BEGAN TO VIBRATE AND THE PILOT BROUGHT THE CYCLIC BACK TO CENTER, ROLLED OFF THE THROTTLE AND VERIFIED THAT THE COLLECTIVE WAS LOWERED. THE HELICOPTER CONTINUED TO SHAKE WITH THE BLADES STRIKING THE GROUND. THE SADDLE FUEL TANK SEPARATED FROM THE HELICOPTER AND A FIRE WAS INITIATED. THE PILOT WAS ABLE TO EVACUATE THE HELICOPTER PRIOR TO ITS BEING CONSUMED BY FIRE. POST ACCIDENT INSPECTION OF HELICOPTER AND ITS COMPONENTS NOT DESTROYED IN THE FIRE FAILED TO REVEAL ANY FAILURE/MALFUNCTION WHICH WOULD HAVE RESULTED IN THE ACCIDENT.
NTSB Probable Cause
THE PILOT'S IMPROPER USE OF COLLECTIVE IN RECOVERING FROM A LOSS OF CONTROL DUE TO GROUND RESONANCE.
Full Narrative
THE PILOT WAS PRACTICING LANDINGS WHEN THE ACCIDENT OCCURRED. THE PILOT STATED HE LOWERED THE COLLECTIVE AND CENTERED THE CYCLIC IN ORDER TO STOP A GROUND RUN DURING THE LANDING. THE HELICOPTER BEGAN TO VIBRATE AND THE PILOT BROUGHT THE CYCLIC BACK TO CENTER, ROLLED OFF THE THROTTLE AND VERIFIED THAT THE COLLECTIVE WAS LOWERED. THE HELICOPTER CONTINUED TO SHAKE WITH THE BLADES STRIKING THE GROUND. THE SADDLE FUEL TANK SEPARATED FROM THE HELICOPTER AND A FIRE WAS INITIATED. THE PILOT WAS ABLE TO EVACUATE THE HELICOPTER PRIOR TO ITS BEING CONSUMED BY FIRE. POST ACCIDENT INSPECTION OF HELICOPTER AND ITS COMPONENTS NOT DESTROYED IN THE FIRE FAILED TO REVEAL ANY FAILURE/MALFUNCTION WHICH WOULD HAVE RESULTED IN THE ACCIDENT.
Flight
Event TypeAccident
Event Time11:45 CDT
Nearest AirportSKYRANCH (0nm)
Runway35
Runway Length2500 ft
Runway Width35 ft
Flight Plan FiledNone
Aircraft FireGrd
Aircraft ExplosionNo
Aircraft
AircraftSchweizer 269C
Tail NumberN7504D
Aircraft CategoryHeli
DamageSubstantial
OperatorUniversity of North Dakota
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · HIO-360-S1A · Reciprocating · 200
Seats2
People & Injuries
Injury Summary1 injury (1 minor injury)
Fatal0
Serious0
Minor1
Uninjured0
Total1
Crew 1Age 22 · First Class
Conditions
ConditionsVMC
LightDaylight
Wind180° @ 5 kt
Visibility15 sm
CeilingNone
Temperature / Dew Point30 C
Altimeter30.00 inHg
Observation Time16:50
Weather SourceWFAC