Heavy seas and rolling motion

[PortsmouthProwler]

Yes, you're right, that's the whole point. A surface vessel rides on top of the wave and gets bounced around. A sub can go below the disturbance; even in a wave of great amplitude, once the sub is well submerged, it's not subject to the same 'roiling' as a surface vessel is.

I grew up on the New England coast and am far from an experienced mariner, but I have been out at sea daily (usually no more than 35 - 50 miles) and know what you're saying. Incidentally, I worked at Portsmouth Naval Shipyard for a while and was on the boats every day while they were overhauled. Some of my more 'lubberly' colleagues would ask some of the submariners about this very point. Most often, they stated they would rather be in the sub and safe below, than on top, in a storm.

[Rosencrantz]

Few notes:

1) If you are using SHIII Commander, you can alter the wave height and get really huge ones. Then it's best to think wind speed be maybe one and half or two times that your OOD tells you.
2) Once I tried to take a look at DD in 5 m/s (10 knt) wind while I was at PD with II-class small boat. Using stadimeter was almost impossible because the pitching and rolling of the boat. I didn't find it very realistic, even if the boat was small, and I think IV has made good progress in that.
At the same time I found also that when looking trough the scope, it didn't look like the waves would run over the scope, as they should. Again I think "One-Four" is doing better.
3) Just couple weeks ago I was reading a fleet boat's War Patrol Report and found they had to take her down to 120 ft in the gale to find a steady water. Saddly I don't remember which boat that was.
4) It's true waves will get more height close to the shore, as the sea bottom gets closer to the surface. However, SHIV is not able to model this and I'm very pleased my processor capacity is not wasted even to try this kind of a task.
5) It might be also true that fleet boats in the IV are a bit too steady while at PD under 30 knt near gale winds. However, if you like pitching and rolling, just take the boat on the surface. Even 10 knt wind is enough to get your boat pitch and roll like a canoo.
6) For the PC sim, it's hard to be realistic enough.


Greetings,
-RC-

[ahclem]

I'm having the opposite problem. Something has glitched in the game and now when my sub is on the surface with smooth seas it is rolling excessively. I'm talking about 30 degree rolls with the crew standing perfectly perpendicular to the deck. It looks really weird, but it's enough to give one DIMS if you stay on the bridge.

Someone mentioned changing the CG. How exactly does one do that?

[vanjast]

Originally Posted by rditto48801

wait, a tsunami?
It skipped my mind earlier that tsunami is the word for giant waves that only are 'visible' close to shore.

Also, aren't tsunamis caused by tremors/quakes on the ocean floor (or islands or on shore), and not by wind/storm activity?

A Wave is energy, either transferred to the sea via wind, or earthquakes.
A tsunami's wave energy is Longitudinal - in the direction of travel, hence it literally has no vertical wave component. When it gets to shallow water, this impulse(s) of energy have nowhere to go except vertical, making very large waves.

Wind storm waves are Transverse waves at 90 degrees (vertical) to the direction of travel. As the waves pass over you (sub) you feel the changes in pressure energy, which causes the rolling depending on your course-vs-wave direction. The deeper you are lessens the pressure variations, thus the rolling effects.

a simple explanation of wave types