Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Leet, West Virginia 25524
Saturday, March 19, 2005 16:36 EST
NTSB Narrative Summary Released at Completion of Accident
While investigating a fire, the pilot noticed an "unusual vibration," and a "needle split" on the rpm gauge. The rotor speed began to decay and the engine speed began to increase. The pilot then entered an autorotation. The helicopter, impacted terrain, was substantially damaged, and a passenger was seriously injured. Examination of the drive train revealed that the main drive pinion, which drove both the main rotor assembly and the tail rotor drive shaft, had failed in fatigue that had initiated in the root of the first (most forward) engaged pinion thread. The failed pinion had been in service for 4,055.4 hours. Including the accident pinion, 10 instances of pinion failures were identified during the investigation. Times in service ranged from 261.5 to 4,243 hours. According to the manufacturer, life limits for the pinion ranged from 6,000 to 8,000 hours depending on application. As a result of this investigation, The FAA issued an SAIB alerting owners and operators of pending revisions to the inspection procedures for the pinion. The manufacturer revised its Handbook of Maintenance Instructions, to include the revised inspection procedures, and submitted design revisions to the FAA to make the part more robust.
NTSB Probable Cause Narrative
A fatigue fracture of the main transmission drive pinion. Also causal was the manufacturer's failure to remove the affected pinions from service during the period that transpired between the initial failures and the accident flight.
Event Information
| Type of Event | Accident |
| Event Date | 3/19/2005 |
| Event Day of the Week | Saturday |
| Time of Event | 1636 |
| Event Time Zone | Eastern Standard Time |
| Event City | Leet |
| Event State | WEST VIRGINIA |
| Event Country | -- |
| Zipcode of the event site | 25524 |
| Event Date Year | 2005 |
| Event Date Month | 3 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 380307N |
| Event Location Longitude | 0815913W |
| 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 | Not pertinent |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1654 Eastern Standard Time |
| Direction of event from weather observation facility (degrees) | 25 |
| Weather Observation Facility ID | CRW |
| Elevation of weather observation facility | 981 |
| Distance of event from weather observation facility (units?) | 38 |
| Time Zone of the weather observation | EST |
| Lighting Conditions | Day |
| Lowest Ceiling Height | 8000 |
| Lowest Non-Ceiling Height | -- |
| Sky/Lowest/Cloud Conditions | Clear |
| Sky Condition for Lowest Ceiling | Broken |
| 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) | -2 |
| Wind Direction (degrees magnetic) | 170 |
| Variable Wind Indicator | Wind direction could be determined |
| Wind Speed (knots) | 16 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Gusting |
| Wind Gust (knots) | 20 |
| Altimeter Setting at event time (in. Hg) | 29.91 |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | -- |
| METAR weather report | -- |
| Event Highest Injury | Serious |
| On Ground, Fatal Injuries | -- |
| On Ground, Minor Injuries | -- |
| On Ground, Serious Injuries | -- |
| Injury Total Fatal | -- |
| Injury Total Minor | -- |
| Injury Total None | 1 |
| Injury Total Serious | 1 |
| Injury Total All | 1 |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | 20048 |
| NTSB Notification Source | CRW FSDO |
| NTSB Notification Date | Mar 21 2005 12:00AM |
| NTSB Notification Time | 1430 |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | Aug 29 2006 3:49PM |
| User who most recently changed record | NTSB\JOHB |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | Charleston, WV |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N61193 |
| NTSB Number | IAD05LA046 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | None |
| Flight plan Was Activated? | No |
| Damage | Substantial |
| Aircraft Fire | None |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | Schweizer |
| Aircraft Model | 269C |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | S1593 |
| Certified Max Gross Weight | 2050 |
| 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 | 3 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Fixed |
| Aircraft, Type of Last Inspection | Annual |
| Date of Last Inspection | Nov 1 2004 12:00AM |
| Airframe hours since last inspection | 65.6 |
| Airframe Hours | 1848.7 |
| ELT Installed | No |
| ELT Activated | No |
| ELT Aided Location of Event Site | No |
| ELT Type | -- |
| Aircraft Owner Name | Marpat Aviation |
| Aircraft Owner Street Address | -- |
| Aircraft Owner City | Switzer |
| Aircraft Owner State | WV |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 25647 |
| Operator is an individual? | No |
| 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 | -- |
| Other Operator of large aircraft? | -- |
| Certified for Part 133 or 137 Operation | External Load |
| 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) | Personal |
| Second Pilot on Board | No |
| Departure Point Same as Event | No |
| Departure Airport Code | WV12 |
| Departure City | S. Charleston |
| Departure State | WV |
| Departure Country | USA |
| Departure Time | 1610 |
| Departure Time Zone | EST |
| Destination Same as Local Flt | -- |
| Destination Airport Code | 6L4 |
| Destination City | Logan |
| Destination State | WV |
| Destination Country | USA |
| Specific Phase of Flight | Maneuvering |
| Report sent to ICAO? | No |
| Evacuation occurred | No |
| Date of most recent change to record | May 11 2006 4:19PM |
| User who most recently changed record | MUZD |
| Since inspection or accident | Time of Accident |
| Event Location Runway Number and Location | NA |
| Runway Length | -- |
| Runway Width | -- |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |