Aircraft Accident/Incident Report

Ovando, Montana 59854
Monday, July 16, 1990 10:30 MDT

NTSB Narrative Summary Released at Completion of Accident

DURING AN EXTERNAL LOAD LOGGING OPERATION, THE PILOT HAD JUST TAKEN OFF FROM REFUELING AND WAS PREPARING FOR ANOTHER LOAD PICK- UP WHEN THE NUMBER ONE ENGINE LOST POWER AND FLAMES WERE OBSERVED SHOTTING OUT FROM THE EXHAUST. THE PILOT TRIED TO FLY THE HELICOPTER ON ONE ENGINE TO A LANDING AREA, HOWEVER, RPM WAS DROPPING. THE PILOT INITIATED AN AUTOROTATION WHICH RESULTED IN A HARD LANDING.

NTSB Probable Cause Narrative

THE PILOT DID NOT MAINTAIN ROTOR RPM AFTER A COMPRESSOR ASSEMBLY BLADE FAILURE. A RELATED FACTOR WAS AN INADEQUATE AUTOROTATION RESULTING IN A HARD LANDING.

Event Information

Type of Event Accident
Event Date 7/16/1990
Event Day of the Week Monday
Time of Event 1030
Event Time Zone Mountain Daylight Time
Event City OVANDO
Event State MONTANA
Event Country --
Zipcode of the event site 59854
Event Date Year 1990
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 0
Degrees magnetic from airport 0
Airport Elevation 0
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) 50
Air Temperature at event time (in degrees celsius) 30
Dew Point at event time (in degress fahrenheit) -18
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) 0
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 1
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 1625
NTSB Notification Source --
NTSB Notification Date Jul 16 1990 12:00AM
NTSB Notification Time 1230
Fiche Number and/or location -used to find docket information 42892
Date of most recent change to record Dec 18 2002 11:28AM
User who most recently changed record NTSB\GIUV
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N439DS
NTSB Number SEA90LA137
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 SIKORSKY
Aircraft Model S-58BT
Aircraft Series Identifier S-58BT
Aircraft Serial Number 58-658
Certified Max Gross Weight 12500
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 2
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection Unknown
Date of Last Inspection --
Airframe hours since last inspection 0
Airframe Hours --
ELT Installed Yes
ELT Activated Yes
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name
Aircraft Owner Street Address
Aircraft Owner City
Aircraft Owner State
Aircraft Owner Country
Aircraft Owner Zipcode
Operator is an individual? --
Operator Name SKYLINE HELICOPTERS
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address P.O. BOX 553
Operator City COLLEGE PARK
Operator State WA
Operator Country
Operator Zip code 99324
Operator Code
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 No
Departure Airport Code
Departure City CANYON CREEK
Departure State MT
Departure Country
Departure Time 1015
Departure Time Zone MDT
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 Hover
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Jan 2 2001 10:35AM
User who most recently changed record dbo
Since inspection or accident --
Event Location Runway Number and Location 0
Runway Length 0
Runway Width 0
Sight Seeing flight No
Air Medical Flight No
Medical Flight --