Aircraft Accident/Incident Report

Kaupo, Hawaii 96713
Monday, October 24, 1994 8:30 HST

NTSB Narrative Summary Released at Completion of Accident

AN EUROCOPTER AS-350D COLLIDED WITH TREES AFTER A LOSS OF POWER WHILE OPERATING IN A MARINE ENVIRONMENT. THE PILOT REPORTED HE HEARD AN EXPLOSION FOLLOWED BY THE ENGINE OUT HORN. THE ENGINE TEMPERATURE (T4) GAUGE WAS NOTED AT 900 DEGREES CELSIUS AND THE ENGINE CHIP DETECTOR LIGHT ILLUMINATED. EXAMINATION REVEALED THAT THE ENGINE HAD SUSTAINED DAMAGE TO THE AXIAL COMPRESSOR, COMPRESSOR STATOR VANES, AND THE IMPELLER. PORTIONS OF THE IMPELLER BLADES WERE EXAMINED MICROSCOPICALLY REVEALING EVIDENCE OF METAL FATIGUE, WITH PITTING EVIDENT THROUGHOUT THE BLADES. ENERGY DISPERSIVE X RAY SHOWED THE PRESENCE OF SULFUR AND CHLORINE IN CORROSION DEPOSITS IN THE PITS. THE ENGINE WAS INSPECTED TWICE IN THE MONTH PRECEDING THE ACCIDENT. THE INSPECTION CRITERIA OUTLINED IN THE ENGINE MAINTENANCE MANUAL DETAILS A VISUAL INSPECTION PROCEDURE OF THE COMPRESSOR SECTION FOR CRACKS. THE MAINTENANCE MANUAL ALSO PRESCRIBES A DAILY COMPRESSOR WATER RINSE TO REMOVE SALT DEPOSITS, FOLLOWED BY INSPECTING THE COMPRESSOR FOR CLEANLINESS.

NTSB Probable Cause Narrative

a total loss of engine power by the corrosion fatigue failure of the compressor impeller due to the failure of company maintenance personnel to perform the prescribed daily compressor wash procedures and the inadequate maintenance inspections, which failed to detect the corrosion and subsequent pitting, that led to the fatigue initiation.

Event Information

Type of Event Accident
Event Date 10/24/1994
Event Day of the Week Monday
Time of Event 830
Event Time Zone Hawaii Standard Time
Event City KAUPO
Event State HAWAII
Event Country --
Zipcode of the event site 96713
Event Date Year 1994
Event Date Month 10
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 Weather Observation Facility
Time of the weather observation 754 Hawaii Standard Time
Direction of event from weather observation facility (degrees) 300
Weather Observation Facility ID OGG
Elevation of weather observation facility 54
Distance of event from weather observation facility (units?) 28
Time Zone of the weather observation HST
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) 15
Air Temperature at event time (in degrees celsius) 24
Dew Point at event time (in degress fahrenheit) 17
Wind Direction (degrees magnetic) 40
Variable Wind Indicator Unknown
Wind Speed (knots) 7
Wind Velocity Indicator Unknown
Wind Gust Indicator Not Gusting
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) 29
Density Altitude (feet) --
Intensity of Precipitation Unknown
METAR weather report --
Event Highest Injury Minor
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal --
Injury Total Minor 4
Injury Total None --
Injury Total Serious --
Injury Total All 4
Investigating Agency NTSB
NTSB Docket Number (internal use) 1959
NTSB Notification Source --
NTSB Notification Date Oct 24 1994 12:00AM
NTSB Notification Time 1238
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Dec 6 2000 12:28PM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N5771L
NTSB Number LAX95LA019
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 135: Air Taxi & Commuter
Type of Flight Plan filed Company VFR
Flight plan Was Activated? --
Damage Substantial
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name EUROCOPTER
Aircraft Model AS-350D
Aircraft Series Identifier AS-350D
Aircraft Serial Number 1343
Certified Max Gross Weight 4300
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 7
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection Annual
Date of Last Inspection Oct 12 1994 12:00AM
Airframe hours since last inspection 53
Airframe Hours 9146
ELT Installed Yes
ELT Activated Yes
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name PAPILLON HELICOPTER, LTD
Aircraft Owner Street Address 2250 KALAKAUA AVE., SUITE 514
Aircraft Owner City HONOLULU
Aircraft Owner State HI
Aircraft Owner Country
Aircraft Owner Zipcode 98034
Operator is an individual? --
Operator Name
Operator Same as Owner? Yes
Operator Is Doing Business As --
Operator Address Same as Owner? Yes
Operator Street Address
Operator City
Operator State
Operator Country
Operator Zip code
Operator Code ILNA
Owner has at least one certificate Yes - certificate holder
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 Non-scheduled
Indicates Domestic or International Flight Domestic
Operator carrying Pax/Cargo/Mail Passenger Only
Type of Flying (Per_Bus / Primary) Unknown
Second Pilot on Board No
Departure Point Same as Event No
Departure Airport Code OGG
Departure City KAHULUI
Departure State HI
Departure Country
Departure Time 800
Departure Time Zone HST
Destination Same as Local Flt dest & departure same, accident can occur anywhere
Destination Airport Code
Destination City
Destination State
Destination Country
Specific Phase of Flight Emergency landing
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Jan 2 2001 10:34AM
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 Yes
Air Medical Flight No
Medical Flight --