Individually Owned: 150,657
Corporate Owned: 137,281
Wittman Regional Airport
Aircraft Accident/Incident Report
Oshkosh, Wisconsin 54902
Friday, August 1, 2014 14:15 CDT
NTSB Narrative Summary Released at Completion of Accident
On August 1, 2014, about 1415 central daylight time, a Mosquito XE amateur-built helicopter, Canadian-registered CF-HEZ was substantially damaged while maneuvering near Wittman Regional Airport (KOSH), Oshkosh, Wisconsin. The private pilot was not injured. Visual meteorological conditions prevailed for the flight. The helicopter was owned and operated by a private individual under the provisions of 14 Code of Federal Regulations Part 91 without a flight plan. The local flight departed approximately 1410.
Just after takeoff, one tail rotor blade separated from the tail rotor and gearbox assembly. The helicopter started to rotate and impacted the ground in a level attitude, spreading both skids out horizontally. Both skids and the tail boom were substantially damaged.
According to the Federal Aviation Administration inspector who examined the helicopter, the tail rotor blade had separated cleanly from the assembly. Neither the collar nor the pins used to secure the blade were located. The inspector reported that the tail rotor assembly was a unique design being tested and was not used in any other application.
The pilot reported that he had been testing this tail rotor design for four years. He stated that a tension/torsion strap and two steel pins were used to retain the blade. The pilot stated that the strap was not completely restricted from movement and over time movement and wear resulted in the failure of the retaining assembly. The pilot reported that there were 82 hours on the tail rotor assembly and it had been 6 hours since it was last inspected.
NTSB Probable Cause Narrative
Not Yet Reported
Event Information
| Type of Event | Accident |
| Event Date | 8/1/2014 |
| Event Day of the Week | Friday |
| Time of Event | 1415 |
| Event Time Zone | Central Daylight Time |
| Event City | Oshkosh |
| Event State | WISCONSIN |
| Event Country | -- |
| Zipcode of the event site | 54902 |
| Event Date Year | 2014 |
| Event Date Month | 8 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 440127N |
| Event Location Longitude | 0883340W |
| Event Location Airport | Wittman Regional Airport |
| Event Location Nearest Airport ID | KOSH |
| Indicates whether the acc/inc occurred off or on an airport | -- |
| Distance from airport in statute miles | 0.5 |
| Degrees magnetic from airport | -- |
| Airport Elevation | 808 |
| Weather Briefing Completeness | -- |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1353 Central Daylight Time |
| Direction of event from weather observation facility (degrees) | -- |
| Weather Observation Facility ID | KOSH |
| Elevation of weather observation facility | 808 |
| Distance of event from weather observation facility (units?) | 5 |
| Time Zone of the weather observation | CDT |
| Lighting Conditions | Day |
| Lowest Ceiling Height | -- |
| Lowest Non-Ceiling Height | 7000 |
| 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) | 27 |
| Dew Point at event time (in degress fahrenheit) | 17 |
| Wind Direction (degrees magnetic) | -- |
| Variable Wind Indicator | Variable |
| Wind Speed (knots) | 3 |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | -- |
| Density Altitude (feet) | -- |
| Intensity of Precipitation | -- |
| METAR weather report | METAR KOSH 011853Z VRB03KT 10SM FEW070 27/17 A3004 |
| 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 | 1 |
| Injury Total Serious | -- |
| Injury Total All | -- |
| Investigating Agency | NTSB |
| NTSB Docket Number (internal use) | -- |
| NTSB Notification Source | FAA |
| NTSB Notification Date | -- |
| NTSB Notification Time | -- |
| Fiche Number and/or location -used to find docket information | -- |
| Date of most recent change to record | Aug 28 2014 12:19PM |
| User who most recently changed record | kaij |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | CF-HEZ |
| NTSB Number | CEN14LA401 |
| 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 | MOSQUITO |
| Aircraft Model | XE |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 1004 |
| Certified Max Gross Weight | 730 |
| Aircraft Category | Helicopter |
| Aircraft Registration Class | -- |
| Aircraft is a homebuilt? | Yes |
| Flight Crew Seats | 1 |
| Cabin Crew Seats | 0 |
| Passenger Seats | 0 |
| Total number of seats on the aircraft | 1 |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Fixed |
| Aircraft, Type of Last Inspection | Conditional |
| Date of Last Inspection | Mar 15 2014 12:00AM |
| Airframe hours since last inspection | -- |
| Airframe Hours | 251 |
| ELT Installed | No |
| ELT Activated | Unknown |
| ELT Aided Location of Event Site | Unknown |
| ELT Type | -- |
| Aircraft Owner Name | John Uptigrove |
| Aircraft Owner Street Address | -- |
| Aircraft Owner City | Calgary |
| Aircraft Owner State | AB |
| Aircraft Owner Country | CA |
| Aircraft Owner Zipcode | T1X0H5 |
| Operator is an individual? | Yes |
| Operator Name | John Uptigrove |
| Operator Same as Owner? | Yes |
| Operator Is Doing Business As | -- |
| Operator Address Same as Owner? | Yes |
| Operator Street Address | -- |
| Operator City | Calgary |
| Operator State | AB |
| Operator Country | CA |
| Operator Zip code | T1X0H5 |
| 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) | Personal |
| Second Pilot on Board | No |
| Departure Point Same as Event | No |
| Departure Airport Code | OSH |
| Departure City | Oshkosh |
| Departure State | WI |
| Departure Country | USA |
| Departure Time | 1410 |
| Departure Time Zone | CDT |
| Destination Same as Local Flt | -- |
| Destination Airport Code | OSH |
| Destination City | Oshkosh |
| Destination State | WI |
| Destination Country | USA |
| Specific Phase of Flight | -- |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Aug 27 2014 3:48PM |
| User who most recently changed record | kaij |
| Since inspection or accident | Time of Accident |
| Event Location Runway Number and Location | N/A |
| Runway Length | -- |
| Runway Width | -- |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |