Narrative:

Vibration in flight. Something hitting windscreen. Reducing power helped vibration. Adding power above that needed for level flight had bad vibration. Made precautionary emergency landing at a landing strip; 2.5 miles off approach pad for runway 21. Due to windy condition had to go-around. Vibration now extreme. Landed. Found prop spinner on hartzel hc-b3z20-1 prop had come apart. Removed rest of spinner and flew aircraft to destination.

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Original NASA ASRS Text

Title: Light aircraft pilot reports landing at private strip after airframe developed significant vibration. Propeller spinner is found to be coming apart and is removed before departing for EWN.

Narrative: Vibration in flight. Something hitting windscreen. Reducing power helped vibration. Adding power above that needed for level flight had BAD vibration. Made precautionary emergency landing at a landing strip; 2.5 miles off approach pad for Runway 21. Due to windy condition had to go-around. Vibration now extreme. Landed. Found prop spinner on Hartzel HC-B3Z20-1 prop had come apart. Removed rest of spinner and flew aircraft to destination.

Data retrieved from NASA's ASRS site as of April 2012 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.