Individually Owned: 150,657
Corporate Owned: 137,281
Whiteman Field Airport
Aircraft Accident/Incident Report
Pacoima, California 91331
Friday, November 12, 2010 7:48 PST
NTSB Narrative Summary Released at Completion of Accident
During a downwind departure from the airport, the engine began to lose power. The pilot initiated an immediate autorotation back toward the airport while adjusting the airspeed and flight controls to clear power lines along the airport boundary. After clearing the power lines, the helicopter settled hard on the runway centerline and then began to rock, slide, and yaw right. The pilot attempted to regain control of the helicopter, and it eventually came to a stop upright on its skids facing about 160 degrees right of the runway centerline. The aft portion of the tail boom had separated.
Postaccident testing and examination of the engine revealed a degraded power turbine (PT) governor spool bearing. Examinations also revealed the presence of diamond particles, which are used in the manufacturing process for the ball bearings, in the governor spool bearing. It is likely that diamond particle contamination caused the governor spool bearing to fail, which rendered the PT governor incapable of modulating governor servo pressure to the fuel control unit. Although no physical evidence was found indicating that the electronic overspeed system activated, the pilot’s statement about two increases in rpm and then a decrease in rpm indicates that the system likely activated. The loss of PT governing ability coupled with the activation of the electronic overspeed system likely resulted in fuel flow oscillations that decreased the fuel flow below the lean blowout limit of the engine and led to the loss of engine power.
NTSB Probable Cause Narrative
The contamination of a spool bearing in the power turbine governor during manufacture, which led to the bearing’s failure in flight, a subsequent loss of engine power during departure, and the resultant hard landing.
Event Information
| Type of Event | Accident |
| Event Date | 11/12/2010 |
| Event Day of the Week | Friday |
| Time of Event | 748 |
| Event Time Zone | Pacific Standard Time |
| Event City | Pacoima |
| Event State | CALIFORNIA |
| Event Country | -- |
| Zipcode of the event site | 91331 |
| Event Date Year | 2010 |
| Event Date Month | 11 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 341534N |
| Event Location Longitude | 1182449W |
| Event Location Airport | Whiteman Field |
| Event Location Nearest Airport ID | WHP |
| Indicates whether the acc/inc occurred off or on an airport | On Airport |
| Distance from airport in statute miles | 0 |
| Degrees magnetic from airport | -- |
| Airport Elevation | 1003 |
| Weather Briefing Completeness | -- |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 753 Pacific Standard Time |
| Direction of event from weather observation facility (degrees) | -- |
| Weather Observation Facility ID | KBUR |
| Elevation of weather observation facility | 778 |
| Distance of event from weather observation facility (units?) | -- |
| Time Zone of the weather observation | PST |
| Lighting Conditions | Day |
| Lowest Ceiling Height | -- |
| Lowest Non-Ceiling Height | -- |
| Sky/Lowest/Cloud Conditions | Clear |
| 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) | 14 |
| Dew Point at event time (in degress fahrenheit) | -4 |
| Wind Direction (degrees magnetic) | -- |
| Variable Wind Indicator | -- |
| Wind Speed (knots) | -- |
| Wind Velocity Indicator | Calm |
| Wind Gust Indicator | -- |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 30.33 |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | -- |
| METAR weather report | -- |
| Event Highest Injury | None |
| On Ground, Fatal Injuries | -- |
| On Ground, Minor Injuries | -- |
| On Ground, Serious Injuries | -- |
| Injury Total Fatal | -- |
| Injury Total Minor | -- |
| Injury Total None | 2 |
| Injury Total Serious | -- |
| Injury Total All | -- |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 32517 |
| NTSB Notification Source | FAA AWP Operations Center |
| NTSB Notification Date | -- |
| NTSB Notification Time | -- |
| Fiche Number and/or location -used to find docket information | -- |
| Date of most recent change to record | Feb 5 2014 11:30AM |
| User who most recently changed record | plah |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N1231A |
| NTSB Number | WPR11FA045 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | None |
| Flight plan Was Activated? | -- |
| Damage | Substantial |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | EUROCOPTER |
| Aircraft Model | AS350B2 |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 3682 |
| Certified Max Gross Weight | 4961 |
| Aircraft Category | Helicopter |
| Aircraft Registration Class | -- |
| Aircraft is a homebuilt? | No |
| Flight Crew Seats | -- |
| Cabin Crew Seats | -- |
| Passenger Seats | -- |
| Total number of seats on the aircraft | 6 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Fixed |
| Aircraft, Type of Last Inspection | 100 Hour |
| Date of Last Inspection | Oct 5 2010 12:00AM |
| Airframe hours since last inspection | -- |
| Airframe Hours | 3456 |
| ELT Installed | Yes |
| ELT Activated | No |
| ELT Aided Location of Event Site | Unknown |
| ELT Type | -- |
| Aircraft Owner Name | Tiny Bubbles, Inc. |
| Aircraft Owner Street Address | -- |
| Aircraft Owner City | Glendale |
| Aircraft Owner State | CA |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 91224 |
| Operator is an individual? | No |
| Operator Name | Tiny Bubbles, Inc. |
| Operator Same as Owner? | Yes |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | Yes |
| Operator Street Address | -- |
| Operator City | Glendale |
| Operator State | CA |
| Operator Country | USA |
| Operator Zip code | 91224 |
| Operator Code | -- |
| Owner has at least one certificate | None |
| 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) | Aerial Observation |
| Second Pilot on Board | No |
| Departure Point Same as Event | Yes |
| Departure Airport Code | WHP |
| Departure City | Pacoima |
| Departure State | CA |
| Departure Country | USA |
| Departure Time | 747 |
| Departure Time Zone | PST |
| Destination Same as Local Flt | dest & departure same, accident can occur anywhere |
| Destination Airport Code | WHP |
| Destination City | Pacoima |
| Destination State | CA |
| Destination Country | USA |
| Specific Phase of Flight | -- |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Feb 5 2014 11:31AM |
| User who most recently changed record | plah |
| Since inspection or accident | Time of Accident |
| Event Location Runway Number and Location | 30 |
| Runway Length | 4120 |
| Runway Width | 75 |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |