Compared with its predecessor, the CP-A offers improved power to weight ratio by 20%, a significant increase in efficiency and a blade foot with decreased exposure to cavitation, thanks to the latest mechanical design and hydrodynamic techniques.
At the same time, the blade foot bearing surfaces have been increased to provide even greater strength and wear-resistance. The system can be supplied with four or five blades of high skew or moderate skew type, conventional or nozzle design.
What next...
Key features of the Rolls-Royce controllable pitch propeller include:
- Two main hub types are available;standard for speeds below 30 knots and H for speeds above 30 knots
- The range of hub sizes will cover powers from approx. 0,5 to 75 MW
- The CP-A hub offers normal pitch control and can also be supplied with full blade feathering
- Bronze or stainless steel blades and hub can be specified, and a version is available in which the blades and blade seals can be exchanged under water
- Open water, nozzle, and ice-class options
- Full US Mil-Spec shock versions are available
What next...
The CP-A is available with three types of oil distribution systems; D-F, I and D-M.
Type D-F OD box in front of gear
![[Image] The oil distribution box is mounted on the forward end of the reduction gearbox. Additional intermediate shafts can be arranged between the propeller shaft and the gearbox.](/Images/CP-Sys-D-F-300x133px_tcm92-39240.gif "[Image] The oil distribution box is mounted on the forward end of the reduction gearbox. Additional intermediate shafts can be arranged between the propeller shaft and the gearbox.")
The oil distribution box is mounted on the forward end of the reduction gearbox. Additional intermediate shafts can be arranged between the propeller shaft and the gearbox.
Type D-M OD box in shaftline
![[Image] A separate shaft carries the oil distribution box, and additional intermediate shafts can be arranged between the propeller shaft and the OD box shaft.](/Images/CP-Sys-I-247x133px_tcm92-39241.gif "[Image] A separate shaft carries the oil distribution box, and additional intermediate shafts can be arranged between the propeller shaft and the OD box shaft.")
A separate shaft carries the oil distribution box, and additional intermediate shafts can be arranged between the propeller shaft and the OD box shaft.
Type I oil distribution integrated in reducton gear
![[Image] Oil distribution integrated in reduction gearbox. The reduction gearbox is a free- standing gearbox intended for integrated propulsion systems.](/Images/CP-Sys-D-M-299x133px_tcm92-39242.gif "[Image] Oil distribution integrated in reduction gearbox. The reduction gearbox is a free- standing gearbox intended for integrated propulsion systems.")
Oil distribution integrated in reduction gearbox. The reduction gearbox is a free-standing gearbox intended for integrated propulsion systems.
What next...
Controllable pitch propellers that meet US Navy standards including Grade-A shock MIL-S-901D are designed and manufactured at our facilities in Walpole and Pascagoula in the USA.
They are the only CPP compliant with US Navy requirement (DOD-P-24562A-SH) and have the highest power density of any naval CPP system. Over 430 vessels use these (former Bird-Johnson) systems. They have been installed on all US Navy vessels equipped with CPPs since 1971 and are available to any size.
Features
- Compliant to US Navy requirement DOD-P-24562A(SH) for shock, noise and vibration.
- Cast and manufactured in the USA
- Mechanical pitch lock for emergency 'take home' capability
- Air emission system minimises underwater noise
- Blades can be changed underwater
What next...
