Big gun cruiser stability

Discussion in 'General' started by crzyhawk, Feb 28, 2008.

  1. crzyhawk

    crzyhawk Well-Known Member

    Joined:
    Feb 25, 2007
    Posts:
    2,306
    Location:
    Alexandria, VA
    Got a question for you big gun gents. You allow cruisers to fire to the side, where as fast gun does not. In fast gun, the primary reason cruisers are not allowed to fire to the sides is safety; cruisers aren't very stable, and it's easy to get rounds coming up high when the ship's roll.

    What kind of stability do you guys see with your cruisers? Do you see any safety issues even with gun armed (as opposed to torpedo armed) crusiers? If so, do you attribute the greater stability to your lower speeds?

    Thanks,

    Mike D
     
  2. Tugboat

    Tugboat Facilitator RCWC Staff Admiral (Supporter)

    Joined:
    Jan 10, 2007
    Posts:
    8,298
    Location:
    Statesboro, GA
    I'd think that the lower rate of fire contributes to less rolling, too :)
     
  3. Kotori87

    Kotori87 Well-Known Member

    Joined:
    Nov 8, 2006
    Posts:
    3,536
    Definitely, the lower rate of fire helps a lot with safety. While the recoil of firing either torpedoes or a gun broadside can rock a small boat significantly, the balls have already left the barrels by the time the ship begins to roll. In effect, the shots travel at whatever the gun angle was when you pulled the trigger. It takes a second or two to recharge the guns for another shot, so the ship has time to slow its rocking and rolling to a point where it's safe to fire again. The low rate of fire has another benefit: because you deal all your damage in a single instant, you can control exactly when you fire. This means you can literally time your shot to "fire on the downward roll", or fire when your ship is perfectly level, or otherwise optimized for the specific level that you want to fire at. In fact, it is a common technique among the cruiser skippers to kick the rudder over just before firing, to make your ship lean towards your target and depress your cannons more in the hope of scoring belows.

    The slower speeds may also help improve stability, though I am not sure to what extent that may be true. I've run my cruiser at scale speed of 50 knots, and I've run it at its historical scale speed of 36.5 knots, and the only big difference I noticed was how much my ship rolls when I turn.

    Another thing that helps improve stability is the extra depth we allow small ships. All Big Gun clubs allow 3/8" of depth added to small ships to help improve their stability, and many allow heavy ballast keels up to 3/8" thick on the underbelly of small ships, to get their center of gravity even lower. My club even goes so far as to permit a whole inch of extra depth (though most skippers stick to 1/2" or less for appearances sake).
     
  4. the frog

    the frog Member

    Joined:
    Feb 27, 2007
    Posts:
    209
    Also as you can see from one of the opening pictures showing the Graff-spee the ship tend to list down on the side the barrels are rotated to. this helps with kill shots and is a byproduct of the cruiser stability on a broadside
     
  5. Rob Wood

    Rob Wood NAMBA Rep

    Joined:
    Mar 1, 2008
    Posts:
    257
    Location:
    Daly City, CA
    Actually, to be honest, side-firing torpedo cannon do tend to shoot high on occasion, but since torpedoes are invariably mounted aiming down, more often than not there's no danger. I think I've been hit, standing on shore, by more battleship main gun richochets than by rolling cruiser torpedoes.

    Most of the cruisers in our club (WWCC) are a bit unstable, but the good skippers have learned to fire on the downward roll. It's very similar to the dynamics of 18th century naval combat in that respect. After all, if the torpedoes fire high, the shot will be wasted.

    Where the problem arises is in the case where the skipper has his torpedoes set up to fire both sides at once. That's a simple way of engineering torpedoes, but if the skipper fires one side on the downward roll, the other side fires high.

    Rob