Easier to list the cons: Added weight & complexity. Either 4 motors & wiring, or 2 motors & two double-output gearboxes Worse turning ability: Driving the outside props means less thrust from inboards for same speed. Inboards are what are putting wash over the rudder(s), which is what turns your ship. Pros: Better accelleration Fouled or stripped prop only results in 25% loss of thrust vice 50% Full sized ships have multiple props because you can only apply so much power to a given size prop efficiently. If you want more thrust, you either need a bigger prop (dimishing returns past a certain size), or multiples. For warships, add the concept of redundancy. In our scale, we can hit max allowed speed (which is way higher than scale speed) for even a Yamato on a single prop. Builders go to larger props combined with drag props in order to get max accelleration and max flow over rudders (see above). In all, may look neat seeing all four screws spinning during a bench test, but useless in practice for our hobby
Single rudder on the USS California so running the 2 middle shafts will give you best turning. one thing to consider is your only going to be allowed 50% more area on your props compared to scale so the super big props are out. So if you want the better acceleration then definitely run all 4 but with the Cali top speed being in the low 20s, 23kts? you are going to need that better turning. Our pond does have a "weeds" issue every once in a while but when you get one prop weeded in it you typically end up with both weeded to some degree although with 4 shafts your chances of limping back to shore and not taking a pounding or worse a surrender because your dead in the water.
The California I helped refit ran all four shafts (sort of). The outer two props were run by small, low-powered motors and had almost no pitch whatsoever. They were essentially drag disks that looked like nice brass props. The inner two props had more powerful motors and 25-pitch props, so they provided all the thrust. That boat handled fairly well, although it still had ballasting/weight distribution issues.
I was thinking 4 props would be cool lookin. the cali does only 21 knots so she doesnt really excel in that department . Im sure when i get it built and on her first battle il get run down and shot to @$#%.
Only 21 knots? Uh oh, Rubberduck, it sounds like your boat is too slow! WWCC enforces a 25-knot minimum speed! J/K, that means any ship slower than 25 knots can be run at 25 knots so it doesn't get blown around by the wind. As far as the whole appearance of four props, that's what I described earlier. You get the appearance of four shafts turning, but the performance of only having two shafts.
Kotori, where is that portion in our rules? I can't find it and our speed chart goes all the way to 20kts.
should be at the very beginning of chapter V, speed. Unless there's been changes I am not aware of, my rulebook dates 2010. "All vessels, except vessels whose prototypes operated at less then 25 knots actual speed, shall run at scale speed. Any vessel whose prototype had a top speed of less than 25 knots may run at 25 knots in scale speed (see speed/time & radar chart below)."
yup there it is. I skimmed right over it haha oops. As for the topic at hand, 4 props does look really cool, My Impero is running all 4 BUT the big difference is she is also running all 3 rudders so the outer props have a dedicated rudder while the inner two share the main. We had it running last season using just a lot of batteries and she was turning quite nicely.
Hahaha kotori i like the 4 prop idea as what was said above i think i will do that. Well 25 knot minimum speed I guess i missed that little tid bit in the rule book my self
