by Guest » December 14, 2020, 3:26 pm
Mac Mackay wrote:Controllable pitch propellors. The angle (pitch) of the propellor blades are adjusted remotely from the bridge of the ship to adjust speed and to reverse. Propellors can be called screws or wheels.
Pitch is not an angle , it is the distance travelled in a forward or aft direction for one turn of the propeller , you multiply the pitch by the rpm and then by 60 minutes and you get the distance travelled in 1 hour ; so the speed of the ship.Of course you have the shape of the hull of the ship which will affect the theoritical speed let say 15% reduction (the slip) and then the wind ,sea and current . The angle of the blades of the prop correspond to a given pitch and is illustrated by an arbitrary scale on the ship's control stick ; 1 to 10 for exemple.
[quote="Mac Mackay"]Controllable pitch propellors. The angle (pitch) of the propellor blades are adjusted remotely from the bridge of the ship to adjust speed and to reverse. Propellors can be called screws or wheels.[/quote]
Pitch is not an angle , it is the distance travelled in a forward or aft direction for one turn of the propeller , you multiply the pitch by the rpm and then by 60 minutes and you get the distance travelled in 1 hour ; so the speed of the ship.Of course you have the shape of the hull of the ship which will affect the theoritical speed let say 15% reduction (the slip) and then the wind ,sea and current . The angle of the blades of the prop correspond to a given pitch and is illustrated by an arbitrary scale on the ship's control stick ; 1 to 10 for exemple.