Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Sierra Blanca, Texas 79851
Monday, December 10, 2001 18:21 MST
NTSB Narrative Summary Released at Completion of Accident
The twin-turbojet, transport-category airplane was destroyed when it departed controlled flight during descent into its final destination and impacted terrain. The flight was cleared to descend from FL 390 to 10,000 feet, and the flight crew established a 4,000-foot/minute descent. As the airplane descended through FL 219, air traffic control requested the pilot contact approach control. However, the pilot read back an incorrect frequency and spoke an unintelligible word. The controller attempted to correct the pilot; however, no additional communications were received from the flight crew. Located within a pause in the pilot's last transmission, a 1680 Hz frequency could be heard for 0.1 seconds. There are only two systems in the airplane with aural warning systems within that frequency range; the cabin altitude warning, and the overspeed warning (both systems were destroyed during the accident sequence). Shortly after the last transmission from the pilot, radar data depicted the airplane climbing back up to FL 231 before entering a steep and rapid descent. A performance study indicated that just prior to the loss of control, the airplane exceeded its maximum operating airspeed of 300 knots calibrated. However, according to the manufacturer, the airplane had been successfully flown at airspeeds up to 400 knots calibrated without loss of control. The right wing and sections of the right horizontal stabilizer/elevator separated from the airplane just prior to its impact with terrain and were located approximately 200-250 feet from the main impact crater. No anomalies with the airframe or engine were found that would have led to the loss of control. A cockpit voice recorder was installed in the accident airplane; however, it did not record the accident flight.
NTSB Probable Cause Narrative
loss of control during descent for undetermined reasons.
Event Information
| Type of Event | Accident |
| Event Date | 12/10/2001 |
| Event Day of the Week | Monday |
| Time of Event | 1821 |
| Event Time Zone | Mountain Standard Time |
| Event City | Sierra Blanca |
| Event State | TEXAS |
| Event Country | -- |
| Zipcode of the event site | 79851 |
| Event Date Year | 2001 |
| Event Date Month | 12 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 313200N |
| Event Location Longitude | 1053733W |
| 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 | -- |
| Degrees magnetic from airport | -- |
| Airport Elevation | -- |
| Weather Briefing Completeness | Unknown |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1751 Mountain Standard Time |
| Direction of event from weather observation facility (degrees) | -- |
| Weather Observation Facility ID | ELP |
| Elevation of weather observation facility | 3958 |
| Distance of event from weather observation facility (units?) | -- |
| Time Zone of the weather observation | MST |
| Lighting Conditions | Night |
| Lowest Ceiling Height | -- |
| Lowest Non-Ceiling Height | 25000 |
| Sky/Lowest/Cloud Conditions | Few |
| Sky Condition for Lowest Ceiling | None |
| Visibility Runway Visual Range (Feet) | -- |
| Visibility Runway Visual Value (Statute Miles) | -- |
| Visibility (Statute Miles) | 10 |
| Air Temperature at event time (in degrees celsius) | 11 |
| Dew Point at event time (in degress fahrenheit) | -1 |
| Wind Direction (degrees magnetic) | 140 |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | 10 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 29.75 |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | -- |
| METAR weather report | -- |
| Event Highest Injury | Fatal |
| On Ground, Fatal Injuries | -- |
| On Ground, Minor Injuries | -- |
| On Ground, Serious Injuries | -- |
| Injury Total Fatal | 2 |
| Injury Total Minor | -- |
| Injury Total None | -- |
| Injury Total Serious | -- |
| Injury Total All | 2 |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 15284 |
| NTSB Notification Source | FAA |
| NTSB Notification Date | Dec 10 2001 12:00AM |
| NTSB Notification Time | 2130 |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | Apr 28 2004 3:34PM |
| User who most recently changed record | NTSB\MONR |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | Albuquerque, New Mexico |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N997TD |
| NTSB Number | FTW02FA048 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | IFR |
| Flight plan Was Activated? | Yes |
| Damage | Destroyed |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | Gates Learjet |
| Aircraft Model | 24D |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 247 |
| Certified Max Gross Weight | 13800 |
| 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 | 8 |
| Number of Engines | 2 |
| Fixed gear or retractable gear | Retractable |
| Aircraft, Type of Last Inspection | AAIP |
| Date of Last Inspection | Sep 10 2001 12:00AM |
| Airframe hours since last inspection | 202.7 |
| Airframe Hours | 7966.4 |
| ELT Installed | No |
| ELT Activated | Unknown |
| 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? | No |
| Operator Name | Air Cargo Express Inc. |
| Operator Same as Owner? | No |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | No |
| Operator Street Address | 11142 West Perimeter Road |
| Operator City | Fort Wayne |
| Operator State | ID |
| Operator Country | USA |
| Operator Zip code | 46809 |
| Operator Code | X5CA |
| Owner has at least one certificate | -- |
| Other Operator of large aircraft? | -- |
| Certified for Part 133 or 137 Operation | -- |
| 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) | Positioning |
| Second Pilot on Board | Yes |
| Departure Point Same as Event | No |
| Departure Airport Code | HRL |
| Departure City | Harlingen |
| Departure State | TX |
| Departure Country | USA |
| Departure Time | 1800 |
| Departure Time Zone | CST |
| Destination Same as Local Flt | -- |
| Destination Airport Code | ELP |
| Destination City | El Paso |
| Destination State | TX |
| Destination Country | USA |
| Specific Phase of Flight | Descent |
| Report sent to ICAO? | No |
| Evacuation occurred | No |
| Date of most recent change to record | Mar 3 2004 3:57PM |
| User who most recently changed record | CASH |
| Since inspection or accident | Time of Accident |
| Event Location Runway Number and Location | -- |
| Runway Length | -- |
| Runway Width | -- |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |