GWX & NYGM sub physics combined, some intresting results

[Ducimus]

Well after more testing, im not sure if one was to call this trimmed down or broken. That funny feeling i got about that 220 mark was apparently well founded.

Here's what i found in regard to this.

If you dive to 220 meters, what happends is the boat gets trimmed down. You in action get true netural boyancy. If you have periscope depth in your config file set at 14 meters. thats exactly what you'll get when ordering periscope depth. Im pretty sure the positive rise near the surface is gone. (maybe ill go back and verify that)

Up until the 220 mark, the boat behaves as normal, except the positive boyancy will bring you all the way to the surface if you let it. But once you pass the 220 mark, im guessing the boat takes on a little bit of water that you can't see in the damage report screen. You seem to honestly and genuinly be trimmed down. So one could think of diving to 220 meters to get rid of the positive boyancy as a real god's honest trim dive. Pretty damn cool.

One small problem. You can't pump that water out. When on the surface again after divign to 220 to Trim the boat for a netural boyancy, your top surface speed will be reduced by about 3-4 kts. So in that part, Lehmann was partially correct.

I just wish i knew why 220 meters was a magical number to the game. I know in the past it was stated by DTB that the boats in SH3 do take on water, but a water leakage below a certain value isnt reported in the damage report screen.

So the one BIG drawback is the subs top surface speed is reduced by around 4 kts after doign a trim dive (220 + meters) . From a design standpoint, to put the subs top speed back to where it should be, it means increase the subs top speed in the sim file on the blind assumption that the player WILL do a trim dive. Likewise the player will know not to do a trim dive and have a 24-25 kt submarine. However, not going below 220 meters is going to rather hard to NOT do and expect to survive.


I think ill leave this open for discussion, im still collecting my thoughts. Not sure how i feel about it right now.

Of course one could always hope that NYGM and GWX teams got together and discussed this one out and ironed the minor details for the sake of a better submodel, everyone would bennfit i think.

Here here....and it would be about bloody time 'n all!

[Ducimus]

There yet may be bloody hope for this.

I reran a test with just NYGM's model and noticed the same behavior on the surface. (IE, loss in top speed because the boat was trimmed down and heavier) Purely out of accident i ran it at flank speed for a couple hours under TC, and something happened.

The boat picked up top speed and behaved as normal again.

I then reran a test with both mods combined.

The top speed was restored after about a couple hours!: up:


Im quite happy about that. This has the potential for maximum coolness.. Im running a few more tests to test what i beleive is neutral boyancy after a "trim dive" is in fact nuetural boyancy, as well as stand still behavior after going that deep.

[Lanzfeld]

I guess the couple of hours represents the pumping out of water?

[Ducimus]

Originally Posted by Lanzfeld

I guess the couple of hours represents the pumping out of water?

I just psuedo timed it. Its about 1 hour.

What make testing this difficult is that a 7C and a 9C submarine behave differently.

For the VIIC heres what i noticed:

At "ahead slow" (100RPMS, aka silent speed), your positive bouancy is such that you do not have enough forward motion to go deeper then 10 meters. Its almost like your being held back by surface tension. At ahead 1/3rd, this is not a problem. Goes down like normal.

The positive boyancy is such that at "ahead slow" (100 RPMS), a type 7c doesnt maintain depth. It slowly draws upwards. In my mind a game breaker, however the saving grace is diving at or a bit past 220 meters.

Once you dive to 220 meters, the boat seems trimmed at pefect neutral boyancy. Going back up to periscope depth, the boat went to 14 meters. Exactly what i specfied in the cfg file. Stopping the engines, it didnt broach the surface. It just stayed put hovering.

About 1 hour in the surface and the boat was back to full positive boyancy.


For the IXC

The behavior is a bit different and im guessing what im seeing is the results of having a greater displacement.

At 100 RPMS, when ordered to dive, an IXC will also hang at 10 meters, however it eventualy push's itself down past that, where as a type 7 didnt in my testing.

At 100 RPMS, an IXC could maintain depth without any upward rise without a "trim dive".

After doing a "trim dive", an IXC still kept its slighly positive rise. Periscope depth ended at 13 meters even though i had specified 14 in the CFG file.

Theres one last behavor i need to test in this regard and it is this:

Normally with the GWX model by itself, if you ordered a depth of 15 meters at 1/3rd, but later on you wanted to raise your depth to say 13-14 meters, all you had to do, was lower your RPMS to have less forward motion (IE go from 1/3rd to ahead slow) and the boat would rise by a meter or two. If an IX has maintained some semblance of neutral boyancy, then it should maintain the same periscope depth regardless of forward motion . This is what i need to go back and test after diving to 220-230 meters.

I'll upload a new test file in a couple mins for othes to try, and then i gotta shut this puppy down and get my ass to work before im late.


EDIT:
Test version that has the 7C and 9C.
http://www.ducimus.net/sh3/release/S...sics_TEST_b.7z

[Lanzfeld]

So what is the latest here. Are you using this combination in your game?

[Ducimus]

Ive got the files together, im just sitting on it for some reason. No one should much interest, no one's apparently tried it and posted more results, so i just stopped looking at it.

The type 7 i think works perfectly as it "probably" should under both, the type 9 i think could use a weee bit of adjusting somewhere, but is probably close enough. Personnaly i think the combo of both is probably for the more hardcore player. I'd use it, but im afraid it will increase my fuel consumption (which is probably realistic. im such a pansy sometimes. lol).

edit:
Seriously though, somebody, D/L the test
http://www.ducimus.net/sh3/release/S...sics_TEST_b.7z

And play around with it in some single missions, and post what you think of it. Id appreiciate it if other people looked at it so i know im not smoking crack here.