Jefferson County Airport
Aircraft Accident/Incident Report

Broomfield, Colorado 80020
Friday, January 19, 1990 15:44 MST

NTSB Narrative Summary Released at Completion of Accident

THE PILOT SAID THAT DURING TAKEOFF GROUND ROLL, THE LEFT ENGINE LOST RPM. THE PILOT LOST DIRECTIONAL CONTROL AND THE PLANE DEPARTED THE LEFT SIDE OF THE RUNWAY. THE PLANE STRUCK A RUNWAY SIGN AND 2 RUNWAY LIGHTS. IT THEN SKIDDED SIDEWAYS FOR 3000 FEET, CROSSED THE RUNWAY AND NOSED DOWN IN A DITCH. THERE WERE HEAVY SNOW SHOWERS IN PROGRESS AT THE TIME OF THE ACDNT AND THE RUNWAY WAS COVERED BY SNOW.

NTSB Probable Cause Narrative

LOSS OF DIRECTIONAL CONTROL BY THE PILOT, DURING TAKEOFF GROUND RUN. CONTRIBUTING TO THIS ACCIDENT WERE A LOSS OF POWER ON THE LEFT ENGINE DUE TO SNOW INGESTION, HEAVY SNOW SHOWERS IN PROGRESS AND AN ICY, SNOW COVERED RUNWAY.

Event Information

Type of Event Accident
Event Date 1/19/1990
Event Day of the Week Friday
Time of Event 1544
Event Time Zone Mountain Standard Time
Event City BROOMFIELD
Event State COLORADO
Event Country --
Zipcode of the event site 80020
Event Date Year 1990
Event Date Month 1
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude
Event Location Longitude
Event Location Airport JEFFERSON COUNTY
Event Location Nearest Airport ID BJC
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 5654
Weather Briefing Completeness Full
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 200
Lowest Non-Ceiling Height 0
Sky/Lowest/Cloud Conditions Partial Obscuration
Sky Condition for Lowest Ceiling Obscured
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 0
Air Temperature at event time (in degrees celsius) -5
Dew Point at event time (in degress fahrenheit) -6
Wind Direction (degrees magnetic) 350
Variable Wind Indicator Unknown
Wind Speed (knots) 9
Wind Velocity Indicator Unknown
Wind Gust Indicator Not Gusting
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) 29
Density Altitude (feet) 5000
Intensity of Precipitation Moderate
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 2
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 438
NTSB Notification Source --
NTSB Notification Date Jan 19 1990 12:00AM
NTSB Notification Time 1558
Fiche Number and/or location -used to find docket information 41373
Date of most recent change to record Dec 12 2000 4:43PM
User who most recently changed record dbo
Basic weather conditions Instrument Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N99SR
NTSB Number DEN90LA047
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed IFR
Flight plan Was Activated? --
Damage Substantial
Aircraft Fire Ground
Aircraft Explosion None
Aircraft Manufacturer's Full Name MITSUBISHI
Aircraft Model MU-2B-25
Aircraft Series Identifier MU-2B-25
Aircraft Serial Number 315
Certified Max Gross Weight 9970
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 6
Number of Engines 2
Fixed gear or retractable gear Retractable
Aircraft, Type of Last Inspection 100 Hour
Date of Last Inspection Aug 14 1989 12:00AM
Airframe hours since last inspection 80
Airframe Hours 1642
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name DEWEY H. COSGROVE
Aircraft Owner Street Address COSCO BLDG.,
Aircraft Owner City CRESTVIEW
Aircraft Owner State FL
Aircraft Owner Country
Aircraft Owner Zipcode 32536
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
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 Yes
Departure Airport Code BJC
Departure City
Departure State
Departure Country
Departure Time 1544
Departure Time Zone MST
Destination Same as Local Flt --
Destination Airport Code CFW
Destination City CRESTVIEW
Destination State FL
Destination Country
Specific Phase of Flight Takeoff
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 29R
Runway Length 9000
Runway Width 100
Sight Seeing flight No
Air Medical Flight No
Medical Flight --