Boatnerd Discussion Forum

The Samuel de Champlain was towed into the large graving dock Thursday afternoon.

Guest wrote:

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.

Info on CPP here:
https://www.marineinsight.com/naval-arc ... eller-fpp/

The SDC is getting an updated CCP system. The vessel currently has a CCP system on it now. It is the original system from being repowered before the Tug ever came to the great lakes. As for operation as with an Airplane the hub will be turning and the propellers will be "pitched" or turned varying degrees starting at zero moving to "full". The system can run at "constant" speed engines up to max RPM and then pitch adjusted for ahead astern up to full either direction. This gives you "instant" power as the main engines are already at full speed. Or operated in "variable" where as the pitch is increased the engine speed slowly comes up. You don't have the instant power band but you can feather your movements when you may want to "crawl" while maneuvering.

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.

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.

Controllable pitch propeller, screw, wheel, etc...

Guest wrote:

statmk wrote:Are they still at Sturgeon Bay? Repairs from fire? Done for year or coming out again? Anyone know status?

They are supposed to be getting new CP wheels.

What are CP wheels?

statmk wrote:Are they still at Sturgeon Bay? Repairs from fire? Done for year or coming out again? Anyone know status?

They are supposed to be getting new CP wheels.

Are they due for a dry docking and 5-year survey? I am not sure the last time they were dry docked for a survey and painting...

Still at Sturgeon Bay as far as I know from when I checked on them this morning.

Are they still at Sturgeon Bay? Repairs from fire? Done for year or coming out again? Anyone know status?