Individually Owned: 150,657
Corporate Owned: 137,281
Aircraft Accident/Incident Report
Kalamazoo, Michigan 49009
Saturday, April 28, 2007 12:52 EDT
NTSB Narrative Summary Released at Completion of Accident
The helicopter was destroyed by impact forces and a post crash fire while attempting an auto-rotation after a mechanical failure. The pilot stated that he was practicing takeoffs, hovering, and quick stops above the runway. After takeoff, at about 50 feet and 50mph, he lowered the collective to initiate a quick stop. At this point the engine RPM revved up out of control. He pulled up on the collective to re-engage the drive system, but the system would not engage. He entered into an auto-rotation, and as he neared the ground the helicopter began to slide sideways, folding the skids under the helicopter. The helicopter then rolled on its side, and the occupants climbed out prior to the post crash fire. Subsequent examination of the helicopter's drive system revealed that the drive shafts, pulleys, and drive belts were intact. The only device within the helicopter drive system that could not be determined to be in working condition was the sprag clutch which transmits engine power to the rotor drive system. The sprag clutch was not examined during the course of the investigation.
NTSB Probable Cause Narrative
The failure of the sprag clutch which resulted in the disengagement of the drive unit and the pilot's misjudged landing during the autorotation. A factor was the low altitude at which the failure occurred.
Event Information
| Type of Event | Accident |
| Event Date | 4/28/2007 |
| Event Day of the Week | Saturday |
| Time of Event | 1252 |
| Event Time Zone | Eastern Daylight Time |
| Event City | Kalamazoo |
| Event State | MICHIGAN |
| Event Country | -- |
| Zipcode of the event site | 49009 |
| Event Date Year | 2007 |
| Event Date Month | 4 |
| MidAir Collision Indicator | No |
| On Ground Collision occurred ? | No |
| Event Location Latitude | 421720N |
| Event Location Longitude | 0854500W |
| Event Location Airport | -- |
| Event Location Nearest Airport ID | PVT |
| Indicates whether the acc/inc occurred off or on an airport | On Airport |
| Distance from airport in statute miles | -- |
| Degrees magnetic from airport | -- |
| Airport Elevation | -- |
| Weather Briefing Completeness | -- |
| Investigator's weather source | Weather Observation Facility |
| Time of the weather observation | 1253 Eastern Daylight Time |
| Direction of event from weather observation facility (degrees) | 90 |
| Weather Observation Facility ID | KAZO |
| Elevation of weather observation facility | 874 |
| Distance of event from weather observation facility (units?) | 9 |
| Time Zone of the weather observation | EDT |
| 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) | 17 |
| Dew Point at event time (in degress fahrenheit) | 8 |
| Wind Direction (degrees magnetic) | -- |
| Variable Wind Indicator | Variable |
| Wind Speed (knots) | -- |
| Wind Velocity Indicator | -- |
| Wind Gust Indicator | Not Gusting |
| Wind Gust (knots) | -- |
| Altimeter Setting at event time (in. Hg) | 29.87 |
| 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) | 21734 |
| NTSB Notification Source | FAA |
| NTSB Notification Date | -- |
| NTSB Notification Time | -- |
| Fiche Number and/or location -used to find docket information | DMS |
| Date of most recent change to record | Jun 27 2007 1:15PM |
| User who most recently changed record | NTSB\lema |
| Basic weather conditions | Visual Meteorological Cond |
| FAA District Office | -- |
Aircraft Involved |
|
|---|---|
Aircraft #1 |
|
| Aircraft Registration Number | N52988 |
| NTSB Number | CHI07CA124 |
| Missing Aircraft Indicator | -- |
| Federal Aviation Reg. Part | Part 91: General Aviation |
| Type of Flight Plan filed | None |
| Flight plan Was Activated? | No |
| Damage | Destroyed |
| Aircraft Fire | Ground |
| Aircraft Explosion | None |
| Aircraft Manufacturer's Full Name | Wilkinson Daniel V |
| Aircraft Model | Rotorway Exec 90 |
| Aircraft Series Identifier | -- |
| Aircraft Serial Number | 1 |
| Certified Max Gross Weight | -- |
| Aircraft Category | Helicopter |
| Aircraft Registration Class | -- |
| Aircraft is a homebuilt? | Yes |
| Flight Crew Seats | -- |
| Cabin Crew Seats | -- |
| Passenger Seats | -- |
| Total number of seats on the aircraft | -- |
| Number of Engines | 1 |
| Fixed gear or retractable gear | Fixed |
| Aircraft, Type of Last Inspection | -- |
| Date of Last Inspection | -- |
| Airframe hours since last inspection | -- |
| Airframe Hours | -- |
| ELT Installed | -- |
| ELT Activated | -- |
| ELT Aided Location of Event Site | -- |
| ELT Type | -- |
| Aircraft Owner Name | Daniel V. Wilkinson |
| Aircraft Owner Street Address | 81 S. Skyview Drive |
| Aircraft Owner City | Kalamazoo |
| Aircraft Owner State | MI |
| Aircraft Owner Country | USA |
| Aircraft Owner Zipcode | 49009 |
| Operator is an individual? | Yes |
| 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 | 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 | Yes |
| Departure Airport Code | 4N0 |
| Departure City | Kalamazoo |
| Departure State | MI |
| Departure Country | USA |
| Departure Time | -- |
| Departure Time Zone | -- |
| Destination Same as Local Flt | dest & departure same, accident can occur anywhere |
| Destination Airport Code | -- |
| Destination City | -- |
| Destination State | -- |
| Destination Country | -- |
| Specific Phase of Flight | Descent - emergency |
| Report sent to ICAO? | -- |
| Evacuation occurred | -- |
| Date of most recent change to record | Jun 22 2007 5:22PM |
| User who most recently changed record | DINC |
| Since inspection or accident | -- |
| Event Location Runway Number and Location | 18 |
| Runway Length | 2697 |
| Runway Width | 125 |
| Sight Seeing flight | No |
| Air Medical Flight | No |
| Medical Flight | -- |