Narrative:

Propeller spinner failed by a portion coming off. It was believed that the slight to moderate vibration that evolved was the propeller leading edge tape coming off; which smoothed out when the loose piece departed the plane. Upon landing at home base; it was discovered that a large portion of the aluminum propeller spinner had broken off. Subsequently; a new composite spinner was ordered and installed (or will be installed) prior to the next flight. Callback conversation with reporter revealed the following information: the reporter stated a vibration was noted in-flight and the reporter believed it was the propeller tape coming off. A short time and the vibration stopped and it was believed the tape departed the aircraft. On the ground; it was discovered 30% of the spinner was missing. This was a costly incident; as the new composite spinner and mount is expensive.

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Original NASA ASRS Text

Title: A C177RG IN CRUISE AT 7500 EXPERIENCED SLIGHT TO MODERATE VIBRATION. SUSPECTED PROP TAPE COMING OFF. ON GND; FOUND 30% OF ALUMINUM SPINNER MISSING.

Narrative: PROP SPINNER FAILED BY A PORTION COMING OFF. IT WAS BELIEVED THAT THE SLIGHT TO MODERATE VIBRATION THAT EVOLVED WAS THE PROP LEADING EDGE TAPE COMING OFF; WHICH SMOOTHED OUT WHEN THE LOOSE PIECE DEPARTED THE PLANE. UPON LNDG AT HOME BASE; IT WAS DISCOVERED THAT A LARGE PORTION OF THE ALUMINUM PROP SPINNER HAD BROKEN OFF. SUBSEQUENTLY; A NEW COMPOSITE SPINNER WAS ORDERED AND INSTALLED (OR WILL BE INSTALLED) PRIOR TO THE NEXT FLT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED A VIBRATION WAS NOTED INFLT AND THE RPTR BELIEVED IT WAS THE PROP TAPE COMING OFF. A SHORT TIME AND THE VIBRATION STOPPED AND IT WAS BELIEVED THE TAPE DEPARTED THE ACFT. ON THE GND; IT WAS DISCOVERED 30% OF THE SPINNER WAS MISSING. THIS WAS A COSTLY INCIDENT; AS THE NEW COMPOSITE SPINNER AND MOUNT IS EXPENSIVE.

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.