Aircraft Accident/Incident Report

Puunene, Maui, Hawaii 96784
Friday, August 5, 1994 12:15 HST

NTSB Narrative Summary Released at Completion of Accident

THE STUDENT WAS PERFORMING A PRACTICE AUTOROTATION AND AT 10 FEET HE BEGAN TO INCREASE THE COLLECTIVE TO CUSHION THE TOUCHDOWN. THE CFI SAID THE MAIN ROTOR RPM WAS LOW AND HE ADDED THROTTLE TO TOUCHDOWN WITH POWER. A GROUND RESONANCE VIBRATION BEGAN AND HE LIFTED OFF THE GROUND. THE VIBRATION CONTINUED AND HE ROLLED THE THROTTLE OFF AND SET THE HELICOPTER ON THE GROUND, THEN IT ROLLED OVER ON ITS SIDE. THE LANDING GEAR DAMPERS AND MAIN ROTOR DAMPERS WERE REMOVED AND TESTED AT THE FACTORY. THE RIGHT REAR AND LEFT FRONT MAIN LANDING GEAR DAMPERS HAD CHARGE PRESSURES BELOW ACCEPTABLE FACTORY SPECS. THE RIGHT FRONT AND LEFT REAR DAMPERS WERE FOUND TO BE WITHIN FACTORY SPEC RANGES. ALL THREE MAIN ROTOR DAMPERS WERE FOUND TO BE ADJUSTED TO EXCESSIVE FRICTION TORQUE VALUES. THE RED BLADE DAMPER WAS ASSEMBLED INCORRECTLY WITH A PLATE STACK UP IMPROPER FOR ANY VERSION OF THE DAMPER ASSEMBLY. THE HELICOPTER WAS IN STORAGE FOR 2 YEARS PRIOR TO JUNE 1994, WHEN IT WAS LEASED TO THE OPERATOR. THE RED BLADE DAMPER HAD BEEN REMOVED FROM ANOTHER HELICOPTER, OVERHAULED, AND PLACED IN SPARE PARTS INVENTORY, THEN PUT ON THE RED BLADE ON JULY 20, 1994.

NTSB Probable Cause Narrative

the improper overhaul of the red blade main rotor damper, and the inadequate maintenance condition of the other rotor dampers and the landing gear dampers, which led to an uncorrectable ground resonance vibration and a subsequent rollover.

Event Information

Type of Event Accident
Event Date 8/5/1994
Event Day of the Week Friday
Time of Event 1215
Event Time Zone Hawaii Standard Time
Event City PUUNENE, MAUI
Event State HAWAII
Event Country --
Zipcode of the event site 96784
Event Date Year 1994
Event Date Month 8
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude
Event Location Longitude
Event Location Airport
Event Location Nearest Airport ID
Indicates whether the acc/inc occurred off or on an airport Off Airport/Airstrip
Distance from airport in statute miles --
Degrees magnetic from airport --
Airport Elevation --
Weather Briefing Completeness Unknown
Investigator's weather source Pilot
Time of the weather observation 0
Direction of event from weather observation facility (degrees) 0
Weather Observation Facility ID
Elevation of weather observation facility 0
Distance of event from weather observation facility (units?) 0
Time Zone of the weather observation
Lighting Conditions Day
Lowest Ceiling Height 0
Lowest Non-Ceiling Height 0
Sky/Lowest/Cloud Conditions Clear
Sky Condition for Lowest Ceiling None
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 20
Air Temperature at event time (in degrees celsius) 29
Dew Point at event time (in degress fahrenheit) --
Wind Direction (degrees magnetic) 50
Variable Wind Indicator Unknown
Wind Speed (knots) 5
Wind Velocity Indicator Unknown
Wind Gust Indicator Not Gusting
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) --
Density Altitude (feet) --
Intensity of Precipitation Unknown
METAR weather report --
Event Highest Injury None
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal --
Injury Total Minor --
Injury Total None 2
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 1638
NTSB Notification Source --
NTSB Notification Date Aug 5 1994 12:00AM
NTSB Notification Time 1510
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Dec 6 2000 12:00PM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N8376F
NTSB Number LAX94LA306
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed None
Flight plan Was Activated? --
Damage Substantial
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name HUGHES
Aircraft Model 269C
Aircraft Series Identifier 269C
Aircraft Serial Number 480679
Certified Max Gross Weight 1670
Aircraft Category Helicopter
Aircraft Registration Class U.S. Registered/U.S. Soil
Aircraft is a homebuilt? No
Flight Crew Seats --
Cabin Crew Seats --
Passenger Seats --
Total number of seats on the aircraft 2
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection Annual
Date of Last Inspection Jun 21 1994 12:00AM
Airframe hours since last inspection 56
Airframe Hours 6999
ELT Installed No
ELT Activated Unknown
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name KUALOA RANCH AND ACTIVITY CLUB
Aircraft Owner Street Address 1000 BISHOP STREET, SUITE 810
Aircraft Owner City HONOLULU
Aircraft Owner State HI
Aircraft Owner Country
Aircraft Owner Zipcode 96813
Operator is an individual? --
Operator Name JAMES C. HOBBS
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address 451 KAIOLOHIA STREET
Operator City KIHEI
Operator State HI
Operator Country
Operator Zip code 96753
Operator Code
Owner has at least one certificate None
Other Operator of large aircraft? No
Certified for Part 133 or 137 Operation Unknown
Operator Certificate Number --
Indicates whether an air carrier operation was scheduled or not --
Indicates Domestic or International Flight --
Operator carrying Pax/Cargo/Mail --
Type of Flying (Per_Bus / Primary) Instructional
Second Pilot on Board Yes
Departure Point Same as Event No
Departure Airport Code OGG
Departure City KAHULUI, MAUI
Departure State HI
Departure Country
Departure Time 1130
Departure Time Zone HST
Destination Same as Local Flt dest & departure same, accident can occur anywhere
Destination Airport Code OGG
Destination City
Destination State HI
Destination Country
Specific Phase of Flight Landing
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Jan 2 2001 10:30AM
User who most recently changed record dbo
Since inspection or accident --
Event Location Runway Number and Location 0
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --