Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Rifle, Colorado 81650
Wednesday, November 24, 1999 12:30 MST
NTSB Narrative Summary Released at Completion of Accident
While on a cross-country positioning flight in cruise flight, the helicopter's engine lost partial power, and the pilot conducted an autorotation to a field, which was rough and uneven. During the landing sequence, the lower wire cutter dug into the uneven ground, the helicopter rocked forward and the skid support cross tubes buckled aft. As the helicopter settled, a main rotor blade struck the left winglet of the horizontal stabilizer, and the tail boom was wrinkled. Examination of the engine revealed that the angular contact ball bearing on the power takeoff shaft had failed. The balls from the bearing had fallen into the gearbox oil sump, and a ball had lodged in the oil exit port, blocking the flow of oil out of the gearbox. The gearbox filled with oil, the oil tank emptied, and power section components began to overheat due to lubricating oil starvation. Engine records provided evidence that during maintenance performed 28.7 hours prior to the engine failure, repair station personnel had removed, inspected and reinstalled the failed bearing. Examination of the bearing provided evidence that it had been pressed apart and reassembled with the outer race reversed. The manufacturer authorizes no disassembly of the bearing. According to the manufacturer, with the outer race reversed, the bearing will immediately start to deteriorate when placed in service.
NTSB Probable Cause Narrative
a forced landing on rough, unsuitable terrain. A contributing factor was the partial loss of engine power, which resulted from improper maintenance by repair station personnel.
Event Information
| Type of Event | Accident |
| Event Date | 11/24/1999 |
| Event Day of the Week | Wednesday |
| Time of Event | 1230 |
| Event Time Zone | Mountain Standard Time |
| Event City | RIFLE |
| Event State | COLORADO |
| Event Country | -- |
| Zipcode of the event site | 81650 |
| Event Date Year | 1999 |
| Event Date Month | 11 |
| 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 | -- |
| Degrees magnetic from airport | -- |
| Airport Elevation | -- |
| Weather Briefing Completeness | Unknown |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1254 Mountain Standard Time |
| Direction of event from weather observation facility (degrees) | 0 |
| Weather Observation Facility ID | RIL |
| Elevation of weather observation facility | 5544 |
| Distance of event from weather observation facility (units?) | 8 |
| Time Zone of the weather observation | MST |
| Lighting Conditions | Day |
| 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) | 10 |
| Air Temperature at event time (in degrees celsius) | 34 |
| Dew Point at event time (in degress fahrenheit) | 16 |
| Wind Direction (degrees magnetic) | 310 |
| Variable Wind Indicator | Unknown |
| Wind Speed (knots) | 4 |
| Wind Velocity Indicator | Unknown |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | 0 |
| Altimeter Setting at event time (in. Hg) | 30 |
| Density Altitude (feet) | 5300 |
| 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 | 1 |
| Injury Total Serious | -- |
| Injury Total All | -- |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 11232 |
| NTSB Notification Source | -- |
| NTSB Notification Date | Nov 24 1999 12:00AM |
| NTSB Notification Time | 1518 |
| Fiche Number and/or location -used to find docket information | IMAGE |
| Date of most recent change to record | Jan 2 2002 7:11AM |
| User who most recently changed record | NTSB\MONR |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N617DE |
| NTSB Number | DEN00GA022 |
| Missing Aircraft Indicator | N |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | Company VFR |
| Flight plan Was Activated? | -- |
| Damage | Substantial |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | Bell |
| Aircraft Model | 206 L-3 |
| Aircraft Series Identifier | 206 L-3 |
| Aircraft Serial Number | 51138 |
| Certified Max Gross Weight | 4150 |
| Aircraft Category | Helicopter |
| 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 | 7 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Fixed |
| Aircraft, Type of Last Inspection | 100 Hour |
| Date of Last Inspection | Nov 3 1999 12:00AM |
| Airframe hours since last inspection | 29 |
| Airframe Hours | 8724 |
| ELT Installed | Yes |
| ELT Activated | Yes |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | DEPARTMENT OF ENERGY |
| Aircraft Owner Street Address | 1627 COLE BLVD, BOX 3402 |
| Aircraft Owner City | GOLDEN |
| Aircraft Owner State | CO |
| Aircraft Owner Country | |
| Aircraft Owner Zipcode | 80401 |
| Operator is an individual? | -- |
| Operator Name | WESTERN AREA POWER ADMIN. |
| Operator Same as Owner? | No |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | No |
| Operator Street Address | 1627 COLE BLVD BOX 3402 |
| Operator City | GOLDEN |
| Operator State | CO |
| Operator Country | |
| Operator Zip code | 80401 |
| 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) | Public Use |
| Second Pilot on Board | No |
| Departure Point Same as Event | No |
| Departure Airport Code | MTJ |
| Departure City | MONTROSE |
| Departure State | CO |
| Departure Country | |
| Departure Time | 1200 |
| Departure Time Zone | MST |
| Destination Same as Local Flt | -- |
| Destination Airport Code | CAG |
| Destination City | CRAIG |
| Destination State | CO |
| Destination Country | |
| Specific Phase of Flight | Cruise |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Dec 1 2001 4:45AM |
| 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 | -- |