Billings Logan Int'l. Airport
Aircraft Accident/Incident Report

Billings, Montana 59105
Friday, December 19, 1986 21:10 MST

NTSB Narrative Summary Released at Completion of Accident

N124AV WAS OPERATING AS BIG SKY AIRLINES FLT 3857, SCHEDULED SERVICE FROM HELENA TO BILLINGS. THE FLT PROCEEDED UNEVENTFULLY UNTIL THE APCH INTO BILLINGS. THE FLT CREW STATED AFTER THE INCIDENT THAT WHEN THE LANDING GEAR WAS EXTENDED, THE LEFT MAIN GEAR LIGHTS DID NOT ILLUMINATE, VERIFYING THE 'DOWN AND LOCKED POSITION..' AFTER NUMEROUS ATTEMPTS TO ILLUMINATE THE LIGHTS AND CONFIRM THE POSITION OF THE LANDING GEAR, THE CREW EXECUTED AN INTENTIONAL GEAR UP LANDING. POST INCIDENT INSPECTION OF THE LANDING GEAR SYSTEM REVEALED IT WAS CAPABLE OF NORMAL OPERATION. THE MALFUNCTIONING COCKPIT INDICATOR LIGHT WAS TRACED BACK TO AN INOPERATIVE OUTBOARD DOWNLOCK MICROSWITCH.

NTSB Probable Cause Narrative

Not Yet Reported

Event Information

Type of Event Incident
Event Date 12/19/1986
Event Day of the Week Friday
Time of Event 2110
Event Time Zone Mountain Standard Time
Event City BILLINGS
Event State MONTANA
Event Country --
Zipcode of the event site 59105
Event Date Year 1986
Event Date Month 12
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude
Event Location Longitude
Event Location Airport BILLINGS LOGAN INT'L.
Event Location Nearest Airport ID BIL
Indicates whether the acc/inc occurred off or on an airport On Airport
Distance from airport in statute miles 0
Degrees magnetic from airport 0
Airport Elevation 3649
Weather Briefing Completeness Not pertinent
Investigator's weather source Weather Observation Facility
Time of the weather observation 2117 Mountain Standard Time
Direction of event from weather observation facility (degrees) 0
Weather Observation Facility ID BIL
Elevation of weather observation facility 3649
Distance of event from weather observation facility (units?) 0
Time Zone of the weather observation MST
Lighting Conditions Night/Dark
Lowest Ceiling Height 20000
Lowest Non-Ceiling Height 14000
Sky/Lowest/Cloud Conditions Scattered
Sky Condition for Lowest Ceiling Overcast
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 20
Air Temperature at event time (in degrees celsius) -1
Dew Point at event time (in degress fahrenheit) -12
Wind Direction (degrees magnetic) 230
Variable Wind Indicator Unknown
Wind Speed (knots) 11
Wind Velocity Indicator Unknown
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 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 13
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 5057
NTSB Notification Source --
NTSB Notification Date Dec 19 1986 12:00AM
NTSB Notification Time 2150
Fiche Number and/or location -used to find docket information 33009
Date of most recent change to record Jan 2 2001 9:14AM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N124AV
NTSB Number DEN87IA032
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 135: Air Taxi & Commuter
Type of Flight Plan filed IFR
Flight plan Was Activated? --
Damage Minor
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name SWEARINGEN
Aircraft Model SA226TC
Aircraft Series Identifier SA226TC
Aircraft Serial Number TC 364
Certified Max Gross Weight 12500
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 15
Number of Engines 2
Fixed gear or retractable gear Retractable
Aircraft, Type of Last Inspection Continuous Airworthiness
Date of Last Inspection Dec 19 1986 12:00AM
Airframe hours since last inspection 36
Airframe Hours 11273
ELT Installed No
ELT Activated No
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name ITT INDUSTRIAL CREDIT COMPANY
Aircraft Owner Street Address P.O. BOX 4377
Aircraft Owner City ST PAUL
Aircraft Owner State MN
Aircraft Owner Country
Aircraft Owner Zipcode 55164
Operator is an individual? --
Operator Name BIG SKY AIRLINES
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address P. O. BOX 31397
Operator City BILLINGS
Operator State MT
Operator Country
Operator Zip code 59107
Operator Code BSAA
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 Only
Type of Flying (Per_Bus / Primary) Unknown
Second Pilot on Board Yes
Departure Point Same as Event No
Departure Airport Code HLN
Departure City HELENA
Departure State MT
Departure Country
Departure Time 1948
Departure Time Zone MST
Destination Same as Local Flt crash at destination city
Destination Airport Code BIL
Destination City BILLINGS
Destination State MT
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 27R
Runway Length 10500
Runway Width 150
Sight Seeing flight No
Air Medical Flight No
Medical Flight --