The hub of a wind-turbine propeller houses the pitch-control ... the actuator motor can turn off while still holding the blade at the proper pitch angle. However, electric pitch-control systems ...

While the primary physical attributes of a propeller — number of blades, diameter and pitch — are well-known ... when a boat’s inclination, aka its running angle, changes — and inclination changes ...

Later came variable-pitch propellers, where the angle of attack of the blades could be increased collectively to take a bigger “bite” of the air for more thrust. This enabled thrust variation ...

Less propeller pitch, more blade surface and less rake usually help boats stay on ... on reciprocal compass headings), note speed and running angle (buy an inexpensive clinometer), plus electronic ...

Beam, overall length, shaft angle and deadrise ... The number of blades depends on the individual boat; similar boats might have ­different results. It is always prudent to work with a top-rated ...

it's still a fixed blade. A variable-pitch propeller allows your boat to shift gears like a car, since it's designed to maintain a low pitch angle during initial acceleration, then shift to a ...

thus making it easier to start the engine with the propeller blades at a low pitch blade angle,” NTSB said. “These locks’ centrifugal latches disengage when the propeller is spinning above a ...