Aircraft Accident/Incident Report

Trading Bay, Alaska 99635
Thursday, April 5, 1990 17:55 AKD

NTSB Narrative Summary Released at Completion of Accident

THE PLT RPRTD THAT WHEN HE TOOK OFF, THERE WAS 1-1/2 TO 2 MI VIS WITH LIGHT SNOW. ABOUT 5 MIN LATER, HE ENCOUNTERED WHITEOUT CONDITIONS & INITIATED A LANDING. HOWEVER, THE HELICOPTER TOUCHDOWN HARD & THE MAIN ROTOR BLADES CONTACTED THE TAIL BOOM, WHICH RESULTED IN EXTENSIVE DAMAGE.

NTSB Probable Cause Narrative

THE PILOT'S INADVERTENT FLIGHT INTO INSTRUMENT METEOROLOGICAL CONDITIONS (IMC). FACTORS RELATED TO THE ACCIDENT WERE: SNOW COVERED TERRAIN, ADVERSE WEATHER CONDITIONS, AND SPATIAL DISORIENTATION OF THE PILOT, DUE TO LACK OF VISUAL CURE DURING THE LANDING.

Event Information

Type of Event Accident
Event Date 4/5/1990
Event Day of the Week Thursday
Time of Event 1755
Event Time Zone --
Event City TRADING BAY
Event State ALASKA
Event Country --
Zipcode of the event site 99635
Event Date Year 1990
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 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 Unknown
Sky Condition for Lowest Ceiling Obscured
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 1
Air Temperature at event time (in degrees celsius) 0
Dew Point at event time (in degress fahrenheit) --
Wind Direction (degrees magnetic) 350
Variable Wind Indicator Unknown
Wind Speed (knots) 25
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 Moderate
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 1
Injury Total Serious --
Injury Total All 4
Investigating Agency NTSB
NTSB Docket Number (internal use) 105
NTSB Notification Source --
NTSB Notification Date Apr 5 1990 12:00AM
NTSB Notification Time 2010
Fiche Number and/or location -used to find docket information 40676
Date of most recent change to record Dec 12 2000 4:53PM
User who most recently changed record dbo
Basic weather conditions Instrument Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N37903
NTSB Number ANC90LA045
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 AEROSPATIALE
Aircraft Model SA-315B
Aircraft Series Identifier SA-315B
Aircraft Serial Number 2565
Certified Max Gross Weight 4850
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 2 1990 12:00AM
Airframe hours since last inspection 22
Airframe Hours 5457
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name PRUDENTIAL CAPITOL GROUP CO.
Aircraft Owner Street Address 155 E. 3300 S.
Aircraft Owner City SALT LAKE CITY
Aircraft Owner State UT
Aircraft Owner Country
Aircraft Owner Zipcode
Operator is an individual? --
Operator Name NTHRN GEOPHYSICAL OF AMERICA
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address 7076 S. ALTON WAY
Operator City ENGLEWOOD
Operator State CO
Operator Country
Operator Zip code 80112
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) Business
Second Pilot on Board No
Departure Point Same as Event No
Departure Airport Code
Departure City DRIFT RIVER
Departure State AK
Departure Country
Departure Time 1750
Departure Time Zone ADT
Destination Same as Local Flt --
Destination Airport Code
Destination City GRANITE POINT
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 10:35AM
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 --