Aircraft Accident/Incident Report

Walla Walla, Washington 99362
Saturday, April 22, 1995 9:50 PDT

NTSB Narrative Summary Released at Completion of Accident

THE PILOT STATED THAT DURING AN EXTERNAL LOAD OPERATION, JUST AFTER THE LOAD CLEARED THE GROUND THE HELICOPTER SHUTTERED AND MADE A LOUD SCRAPING NOISE FOLLOWED BY LOW ROTOR RPM. THE PILOT RELEASED THE LOAD AND MANEUVERED FOR AN EMERGENCY LANDING. DURING THE MANEUVER, THE HELICOPTER COLLIDED WITH TREES. DURING THE POST CRASH INSPECTION, IT WAS FOUND THAT THE FREEWHEELING ONE-WAY CLUTCH ASSEMBLY HAD FAILED IN FLIGHT. THE CLUTCH ASSEMBLY APPEARED TO BE WORN AND THE INNER CLUTCH RACE DISPLAYED SIGNS OF BRINELLING.

NTSB Probable Cause Narrative

TOTAL FAILURE OF THE FREEWHEELING SPRAG UNIT. A FACTOR TO THE ACCIDENT WAS: SUITABLE TERRAIN WAS NOT AVAILABLE FOR LANDING.

Event Information

Type of Event Accident
Event Date 4/22/1995
Event Day of the Week Saturday
Time of Event 950
Event Time Zone Pacific Daylight Time
Event City WALLA WALLA
Event State WASHINGTON
Event Country --
Zipcode of the event site 99362
Event Date Year 1995
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 --
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) 30
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 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 Serious
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal --
Injury Total Minor --
Injury Total None --
Injury Total Serious 1
Injury Total All 1
Investigating Agency NTSB
NTSB Docket Number (internal use) 248
NTSB Notification Source --
NTSB Notification Date Apr 22 1995 12:00AM
NTSB Notification Time 1115
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Dec 7 2000 4:13PM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N39SD
NTSB Number SEA95LA078
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 133: Rotorcraft Ext. Load
Type of Flight Plan filed None
Flight plan Was Activated? --
Damage Substantial
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name BELL
Aircraft Model UH-1B
Aircraft Series Identifier UH-1B
Aircraft Serial Number 63-8699
Certified Max Gross Weight 8500
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 6
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection Annual
Date of Last Inspection Apr 8 1995 12:00AM
Airframe hours since last inspection 34
Airframe Hours 4810
ELT Installed No
ELT Activated Unknown
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name BLUE MOUNTAIN HELICOPTER INC.
Aircraft Owner Street Address 1820 S. MAIN ST.
Aircraft Owner City MILTON
Aircraft Owner State OR
Aircraft Owner Country
Aircraft Owner Zipcode 97862
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 GASL
Owner has at least one certificate Yes - certificate holder
Other Operator of large aircraft? No
Certified for Part 133 or 137 Operation External Load
Operator Certificate Number --
Indicates whether an air carrier operation was scheduled or not Unknown
Indicates Domestic or International Flight Unknown
Operator carrying Pax/Cargo/Mail Unknown
Type of Flying (Per_Bus / Primary) Other Work Use
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 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 No
Air Medical Flight No
Medical Flight --