Most piston-engine pilots habitually hand-rotate their propeller for various reasons: to orient the blades horizontally for tiedown in close quarters or vertically for parking in the rain, to "loosen the oil" prior to starting in cold weather, etc. The author used to do this, too, until his prop unexpectedly started to spin after hand rotation one cold morning...with nearly catastrophic results. After researching the subject carefully, and came to the conclusion that there are no compelling reasons ever to hand-rotate a propeller. Here's why.
By Paul D. Adler
, This article originally appeared in Boston FSDO's COMMUNICATOR. | April 28, 1997