Aircraft Accident/Incident Report

Pacific Ocean
Thursday, April 9, 1992 17:00 PDT

NTSB Narrative Summary Released at Completion of Accident

THE HELICOPTER WAS COMPLETING AN AERIAL OBSERVATION FLIGHT (FISH SPOTTING) OVER THE PACIFIC OCEAN NEAR THE ISLAND OF CANTON AND WAS LANDING ON THE SHIP'S HELIPAD. WHEN THE SKIDS TOUCHED DOWN, THE ROTOR MAST ASSEMBLY SEPARATED FROM THE ROTOR MAST BASE CAUSING THE HELICOPTER TO TURN TO THE LEFT 90 DEGREES. THE ROTOR MAST ASSEMBLY AND ALL ITS COMPONENTS FELL INTO THE OCEAN AND WERE NOT RECOVERED. THE HELICOPTER SUSTAINED SUBSTANTIAL DAMAGE. THE PILOT REPORTED THAT THE HELICOPTER DID NOT EXPERIENCE ANY ABNORMAL CYCLIC MOVEMENTS OR ANY UNUSUAL VIBRATIONS BEFORE THE OCCURRENCE. THE HELICOPTER HAD ACCRUED 328.5 HOURS SINCE THE LAST ANNUAL INSPECTION. A 300-HOUR AND A 100-HOUR INSPECTION HAD RECENTLY BEEN COMPLETED. METALLURGICAL EXAMINATION OF THE ROTOR MAST BASE FRACTURE SURFACES REVEALED OVERLOAD CHARACTERISTICS WITH SOME POST FRACTURE MECHANICAL SMEARING AND DAMAGE. NO EVIDENCE OF ANY CORROSION OR FATIGUE WAS FOUND. THE HARDNESS MEASUREMENTS COMPLIED WITH THE MATERIAL SPECIFICATIONS.

NTSB Probable Cause Narrative

AN UNDETERMINED FAILURE IN THE ROTOR SYSTEM.

Event Information

Type of Event Accident
Event Date 4/9/1992
Event Day of the Week Thursday
Time of Event 1700
Event Time Zone Pacific Daylight Time
Event City PACIFIC OCEAN
Event State PACIFIC OCEAN
Event Country --
Zipcode of the event site
Event Date Year 1992
Event Date Month 4
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 0
Degrees magnetic from airport 0
Airport Elevation --
Weather Briefing Completeness Unknown
Investigator's weather source Witness
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) --
Dew Point at event time (in degress fahrenheit) --
Wind Direction (degrees magnetic) 0
Variable Wind Indicator Unknown
Wind Speed (knots) 0
Wind Velocity Indicator Unknown
Wind Gust Indicator Unknown
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) --
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 2
Injury Total None --
Injury Total Serious --
Injury Total All 2
Investigating Agency NTSB
NTSB Docket Number (internal use) 2730
NTSB Notification Source --
NTSB Notification Date --
NTSB Notification Time 0
Fiche Number and/or location -used to find docket information 47516
Date of most recent change to record Dec 11 2000 2:51PM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N8311F
NTSB Number LAX92LA175
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 369C
Aircraft Series Identifier 369C
Aircraft Serial Number 460806S
Certified Max Gross Weight 3000
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 5
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection 100 Hour
Date of Last Inspection Apr 1 1992 12:00AM
Airframe hours since last inspection 42
Airframe Hours 11013
ELT Installed Unknown
ELT Activated Unknown
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name VOYAGER, INC
Aircraft Owner Street Address P.O. BOX 82598
Aircraft Owner City SAN DIEGO
Aircraft Owner State CA
Aircraft Owner Country
Aircraft Owner Zipcode 92101
Operator is an individual? --
Operator Name VOYAGER, INC
Operator Same as Owner? Yes
Operator Is Doing Business As --
Operator Address Same as Owner? Yes
Operator Street Address P.O. BOX 82598
Operator City SAN DIEGO
Operator State CA
Operator Country
Operator Zip code 92101
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) Aerial Observation
Second Pilot on Board No
Departure Point Same as Event Yes
Departure Airport Code
Departure City
Departure State
Departure Country
Departure Time 0
Departure Time Zone
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 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 No
Air Medical Flight No
Medical Flight --