Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Denver, Colorado 80207
Friday, December 14, 1990 21:10 MST
NTSB Narrative Summary Released at Completion of Accident
AS THE FLIGHT WAS CLIMBING THROUGH FL210, THE CREW HEARD AN EXPLOSION AND FLAMES WERE SEEN COMING FROM THE TAILPIPE OF NO.3 ENGINE. THE ENGINE WAS SECURED AND THE AIRPLANE LANDED UNEVENTFULLY. EXAMINATION REVEALED AN UNCONTAINED FAILURE. A PREEXISTING CRACK WAS FOUND IN THE NO.12 BLADE ON THE 4TH STAGE TURBINE WHEEEL. MAINTENANCE RECORDS DISCLOSED THE WHEEL HAD RECENTLY UNDERGONE A DYE PENETRANT INSPECTION. NO CRACKS WERE NOTED. THE ENGINE HAD ACCRUED 99 CYCLES AND 66 HOURS OVER A PERIOD OF 13 DAYS FROM THE TIME OF THE LAST INSPECTION AND THE TIME OF THE ENGINE FAILURE.
NTSB Probable Cause Narrative
THE CATASTROPHIC FAILURE OF THE NO.12 BLADE ON THE 4TH STAGE TURBINE WHEEL, AND FAILURE OF COMPANY MAINTENANCE PERSONNEL TO IDENTIFY THE PREEXISTING CRACK DURING MAINTENANCE INSPECTION.
Event Information
| Type of Event | Incident |
| Event Date | 12/14/1990 |
| Event Day of the Week | Friday |
| Time of Event | 2110 |
| Event Time Zone | Mountain Standard Time |
| Event City | DENVER |
| Event State | COLORADO |
| Event Country | -- |
| Zipcode of the event site | 80207 |
| Event Date Year | 1990 |
| Event Date Month | 12 |
| 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 | Not pertinent |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 2050 Mountain Standard Time |
| Direction of event from weather observation facility (degrees) | 0 |
| Weather Observation Facility ID | DEN |
| Elevation of weather observation facility | 5333 |
| Distance of event from weather observation facility (units?) | 0 |
| Time Zone of the weather observation | MST |
| Lighting Conditions | Night/Dark |
| 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) | 20 |
| Air Temperature at event time (in degrees celsius) | -18 |
| 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 | 57 |
| Injury Total Serious | -- |
| Injury Total All | -- |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 5048 |
| NTSB Notification Source | -- |
| NTSB Notification Date | Dec 15 1990 12:00AM |
| NTSB Notification Time | 2130 |
| Fiche Number and/or location -used to find docket information | 43995 |
| 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 | N609AW |
| NTSB Number | DEN91IA026 |
| 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 | BRITISH AEROSPACE |
| Aircraft Model | BAE 146-200 |
| Aircraft Series Identifier | BAE 146-20 |
| Aircraft Serial Number | E2070 |
| Certified Max Gross Weight | 95000 |
| 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 | 100 |
| Number of Engines | 4 |
| Fixed gear or retractable gear | Retractable |
| Aircraft, Type of Last Inspection | Unknown |
| Date of Last Inspection | -- |
| Airframe hours since last inspection | 0 |
| Airframe Hours | -- |
| ELT Installed | No |
| ELT Activated | No |
| 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 | AIR WISCONSIN, INC. |
| Operator Same as Owner? | No |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | No |
| Operator Street Address | 203 CHALLENGER DR. |
| Operator City | APPLETON |
| Operator State | WI |
| Operator Country | |
| Operator Zip code | 54915 |
| Operator Code | AWAA |
| 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 | Yes |
| Departure Airport Code | |
| Departure City | |
| Departure State | |
| Departure Country | |
| Departure Time | 2053 |
| Departure Time Zone | MST |
| Destination Same as Local Flt | -- |
| Destination Airport Code | ASE |
| Destination City | ASPEN |
| Destination State | CO |
| Destination Country | |
| Specific Phase of Flight | Climb |
| 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 | 0 |
| Runway Length | -- |
| Runway Width | -- |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |