The basic steering system, manual and electronic, is now installed in the first FPB 64 and perhaps some discussion is in order. To begin with there are several important details in view in the photo above:
- There are two totally independent hydraulic systems, either of which can steer the boat.
- There is provision for an emergency tiller (supplied with relieving tackles).
- Robust rudder stops are designed into the system from the beginning (not as an afterthought).
- Two independent auto pilot systems are installed. There is sufficient cabling so that plugs can be switched between primary and secondary pilots. This way you could use the port rudder angle sensor with the starboard pilot control head (each pilot has a control head, junction box, rudder angle sensor, motor controller, and hydraulic pump).
One of the two independent systems has a manual pump, with a removable steering wheel, mounted at the inside helm station. This is intended as a backup with normal steering being done with electronic controls.
The rudder to which this gear is attached is enormous, several times the size of what is normally fitted to yachts of this type. We willingly pay the drag penalties associated with this oversized rudder in return for the wonderful control it gives us at sea and in close quarters maneuvering.
Posted by Steve Dashew (October 16, 2009)
January 5th, 2010 at 8:39 pm
Hello Steve,
The single rudder is indeed massive and it seems that the aluminium framing has been designed so that the lower third will be sacrificed in case of collision…
I wonder if you have looked into twin flanking rudders of approximately the same surface area as the single one, the advantages being:
– Excellent handling at slow speed with single engine…
– Nothing to impede the water flow from the single propeller…
– Removal of shaft made easier…
– No rudder area protruding below the heel of the keel…
Also, when a rudder gets hit, the shaft may be bent, preventing rotation: having the ability to drop down the rudder shaft an inch, or so would likely restore steering…
January 6th, 2010 at 11:35 am
Hi Frank:
We looked hard at twin rudders on the 64. The main advantage is low speed maneuverability. However, there are three disadvantages. First, the rudder is unprotected by the prop skeg. Second, it is signigicantly more complexand takes extra room in the engine room. Third, in heavy weather steering in turbulent sea states twins have less depth than a single.
Our logic is to go oversize with a single blade for maneuvering in port and heavy weather steering. This rudder is protected by the prop skeg.
Regarding dropping a rudder with a bent shaft, there is an allowance for this in our boats. However, we are happy to report to our knowledge t his has never been employed.