912 and Warp Drive fixed pitch, 3 blade prop.
(Standard engine/spinner/propeller installation)
I lost a spinner front-plate screw on Sunday during flight. It 'nicked' the
leading edge of the W.D. prop., near the hub. The damage is repairable, but
it might have been worse.
I'm almost certain I tightened it just a few hours previously.
Now included in my pre-flight is a check of all external spinner attachment
screws, especially those forward of the propeller.
I suppose it's possible that frequent removal/replacment of the spinner cone
increases the likelyhood that this may happen, due to degraded 'grip' offered
by the screw thread.
With just two points of attachment to the cone, front-plate vibration increased
significantly (at certain rev.-ranges) to a detectable level. That's how it got
noticed !
Safe flying,
alan
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