Aircraft Accident/Incident Report

Dutch Harbor, Alaska 99692
Monday, July 11, 1983 16:23 AKD

NTSB Narrative Summary Released at Completion of Accident

APRX 2 MIN AFTER TAKEOFF, THE PLT & PASSENGERS HEARD A LOUD MUFFLED BOOM FROM BEHIND THE FIREWALL, THEN THE ROTOR RPM BEGAN TO DECAY. THE PLT ENTERED AN AUTOROTATION & SELECTED A LANDING AREA. HE NOTED THAT THE ENG WAS NOT DRIVING THE ROTOR SYS, SO HE SHUT IT DOWN TO REDUCE THE POSSIBILITY OF FIRE WHILE LANDING. DURING AN EMERGENCY LANDING ON SLOPING, MOUNTAINOUS TERRAIN, THE HELICOPTER ROLLED OVER, AND SUBSEQUENTLY, IT CAME TO REST IN A RAVINE AT THE BOTTOM OF THE SLOPE. A TEARDOWN OF THE ENG REVEALED THAT THE #3 BEARING, PN 4-301-051-02, HAD FAILED & THAT THE OIL JET FOR THE BEARING WAS CLOGGED. REPORTEDLY, MAINTENANCE PERSONNEL WERE AWARE THAT A DIFFERENTIAL PRESSURE CHECK, TO DETECT CLOGGING TO THE #2 & #3 PACKAGED OIL JETS, WAS 7 TO 8 PSI. THIS WAS 2 TO 3 PSI TOO HIGH & INDICATED CLOGGING OF THE OIL JETS. (THIS PROCEDURE WAS OUTLINED IN LYCOMING SVC BULLETIN LTS101A-17-0014). HOWEVER, THE DISCREPANCY WAS NOT ENTERED IN THE ENG MAINTENANCE LOGS.

NTSB Probable Cause Narrative

Not Yet Reported

Event Information

Type of Event Accident
Event Date 7/11/1983
Event Day of the Week Monday
Time of Event 1623
Event Time Zone --
Event City DUTCH HARBOR
Event State ALASKA
Event Country --
Zipcode of the event site 99692
Event Date Year 1983
Event Date Month 7
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 10
Degrees magnetic from airport 228
Airport Elevation --
Weather Briefing Completeness Not pertinent
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 2000
Sky/Lowest/Cloud Conditions Scattered
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) 10
Dew Point at event time (in degress fahrenheit) --
Wind Direction (degrees magnetic) 0
Variable Wind Indicator Unknown
Wind Speed (knots) 0
Wind Velocity Indicator Calm
Wind Gust Indicator Not Gusting
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) 30
Density Altitude (feet) --
Intensity of Precipitation Unknown
METAR weather report --
Event Highest Injury Serious
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal --
Injury Total Minor 3
Injury Total None --
Injury Total Serious 1
Injury Total All 4
Investigating Agency NTSB
NTSB Docket Number (internal use) 2307
NTSB Notification Source --
NTSB Notification Date --
NTSB Notification Time 0
Fiche Number and/or location -used to find docket information 22643
Date of most recent change to record Jan 2 2001 9:15AM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N141EH
NTSB Number ANC83FA122
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 Destroyed
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name AEROSPATIALE
Aircraft Model AS-350D
Aircraft Series Identifier AS-350D
Aircraft Serial Number 1460
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 5
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection Continuous Airworthiness
Date of Last Inspection Jul 11 1983 12:00AM
Airframe hours since last inspection --
Airframe Hours 813
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name ERA HELICOPTERS, INC.
Aircraft Owner Street Address 6160 S. AIRPARK DR.
Aircraft Owner City ANCHORAGE
Aircraft Owner State AK
Aircraft Owner Country
Aircraft Owner Zipcode 99502
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
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
Departure City
Departure State
Departure Country
Departure Time 1620
Departure Time Zone
Destination Same as Local Flt --
Destination Airport Code DUT
Destination City DUTCH HARBOR
Destination State AK
Destination Country
Specific Phase of Flight Landing
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Jan 2 2001 10:36AM
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 --