Unalaska Airport
Aircraft Accident/Incident Report

Unalaska, Alaska 99692
Wednesday, February 13, 1991 12:39 AST

NTSB Narrative Summary Released at Completion of Accident

THE RUNWAY ALIGNS FROM THE SOUTHEAST TO THE NORTHWEST AND WITHIN 150 FEET EAST OF THE RUNWAY IS A 1,634 FOOT HIGH MOUNTAIN. THE WIND WAS FROM THE NORTHWEST AT 14 KNOTS, GUSTING TO 25 KNOTS. THE LANDING THRESHOLD FOR RUNWAY 30 WAS DIRECTLY DOWNWIND OF THE MOUNTAIN. DURING THE FINAL APPROACH, THE FIRST OFFICER NOTICED A PLUS 30 KNOT DEVIATION IN THE AIRSPEED AND CALLED FOR THE CAPTAIN TO INITIATE A GO AROUND. THE CAPTAIN HAD ALREADY APPLIED POWER WHEN THE AIRPLANE BEGAN TO SINK AND ROLL TO THE RIGHT. THE RIGHT WING TIP SCRAPED THE RUNWAY SURFACE DURING THE GO AROUND.

NTSB Probable Cause Narrative

THE WINDSHEAR ENCOUNTERED ON SHORT FINAL. CONTRIBUTING TO THE ACCIDENT WAS THE RISING TERRAIN WITHIN 150 FEET OF THE RUNWAY, THE VARIABLE NATURE OF THE WIND DUE TO THE RISING TERRAIN, AND THE PILOT'S FAILURE TO MAINTAIN LATERAL CONTROL DURING THE GO AROUND.

Event Information

Type of Event Incident
Event Date 2/13/1991
Event Day of the Week Wednesday
Time of Event 1239
Event Time Zone Atlantic Standard Time
Event City UNALASKA
Event State ALASKA
Event Country --
Zipcode of the event site 99692
Event Date Year 1991
Event Date Month 2
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude
Event Location Longitude
Event Location Airport UNALASKA
Event Location Nearest Airport ID DUT
Indicates whether the acc/inc occurred off or on an airport On Airport
Distance from airport in statute miles --
Degrees magnetic from airport --
Airport Elevation 22
Weather Briefing Completeness Full
Investigator's weather source Weather Observation Facility
Time of the weather observation 1150 Atlantic Standard Time
Direction of event from weather observation facility (degrees) 200
Weather Observation Facility ID DUT
Elevation of weather observation facility 22
Distance of event from weather observation facility (units?) 1
Time Zone of the weather observation AST
Lighting Conditions Day
Lowest Ceiling Height 2700
Lowest Non-Ceiling Height 0
Sky/Lowest/Cloud Conditions Unknown
Sky Condition for Lowest Ceiling Broken
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 6
Air Temperature at event time (in degrees celsius) -2
Dew Point at event time (in degress fahrenheit) -4
Wind Direction (degrees magnetic) 350
Variable Wind Indicator Unknown
Wind Speed (knots) 15
Wind Velocity Indicator Unknown
Wind Gust Indicator Unknown
Wind Gust (knots) 26
Altimeter Setting at event time (in. Hg) 29
Density Altitude (feet) --
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 46
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 5037
NTSB Notification Source --
NTSB Notification Date --
NTSB Notification Time 0
Fiche Number and/or location -used to find docket information 45884
Date of most recent change to record Dec 12 2000 9:19AM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N672MA
NTSB Number ANC91IA028
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 121: Air Carrier
Type of Flight Plan filed IFR
Flight plan Was Activated? --
Damage Minor
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name BOEING
Aircraft Model 737-200
Aircraft Series Identifier 737-200
Aircraft Serial Number
Certified Max Gross Weight 104000
Aircraft Category Airplane
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 50
Number of Engines 2
Fixed gear or retractable gear Retractable
Aircraft, Type of Last Inspection Unknown
Date of Last Inspection Jan 2 2000 12:00AM
Airframe hours since last inspection --
Airframe Hours --
ELT Installed No
ELT Activated No
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name MARKAIR, INC.
Aircraft Owner Street Address 4100 W. INTERNAT'L AIRPORT RD
Aircraft Owner City ANCHORAGE
Aircraft Owner State AK
Aircraft Owner Country
Aircraft Owner Zipcode 99502
Operator is an individual? --
Operator Name MARKAIR, INC.
Operator Same as Owner? Yes
Operator Is Doing Business As --
Operator Address Same as Owner? Yes
Operator Street Address 4100 W. INTERNAT'L AIRPORT RD
Operator City ANCHORAGE
Operator State AK
Operator Country
Operator Zip code 99502
Operator Code MRKA
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 Scheduled
Indicates Domestic or International Flight Domestic
Operator carrying Pax/Cargo/Mail Passenger/Cargo
Type of Flying (Per_Bus / Primary) Unknown
Second Pilot on Board Yes
Departure Point Same as Event No
Departure Airport Code ANC
Departure City ANCHORAGE
Departure State AK
Departure Country
Departure Time 1030
Departure Time Zone AST
Destination Same as Local Flt crash at destination city
Destination Airport Code DUT
Destination City UNALASKA
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 10:30AM
User who most recently changed record dbo
Since inspection or accident --
Event Location Runway Number and Location 3
Runway Length 3800
Runway Width 100
Sight Seeing flight No
Air Medical Flight No
Medical Flight --