NTSB Identification: IAD03IA017.
The docket is stored in the Docket Management System (DMS). Please contact Records Management Division
Incident occurred Tuesday, October 22, 2002 in LEESBURG, VA
Probable Cause Approval Date: 08/26/2003
Aircraft: CRAIG N. MOEN RV-8, registration: N184CM
Injuries: 1 Uninjured.

NTSB investigators used data provided by various sources and may not have traveled in support of this investigation to prepare this aircraft incident report.

While in the traffic pattern, the engine backfired a few times. After landing, and while taxiing to the ramp, the pilot determined that the right ignition source was working intermittently. He was unable to replace the right ignition source and departed the following day. As the airplane made a normal descent into the final destination airport, the pilot discovered the right ignition source was "completely dead." The pilot had replaced both magnetos with a Dual Lightspeed Plasma II ignition system with Hall Effect Sensor Modules. After landing at the final destination airport, the pilot removed the back plate of the right Hall Effect sensor module and found that the timing rotor had fractured, and that the internal face of the back plate exhibited rotational scoring. Subsequent Safety Board examination revealed that the timing rotor had failed due to low-stress, high-cycle fatigue. According to the manufacturer, 400 timing rotors were in use, and there were no reported failures.

The National Transportation Safety Board determines the probable cause(s) of this incident to be:

A low-stress, high-cycle fatigue fracture of the right ignition timing rotor.

Full narrative available

Index for Oct2002 | Index of months