Submarine Speed Above Vs. Underwater

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i've built 3 german style U-boats now, and i've noticed something very strange. while traveling on the surface the U-boat is a lot slower than when it is fully submereged. no, i didn't switch to different motors, it is the same motors at the same throttle above and below the surface. while on the surface it will go 8 m/s but submereged it shoots up to a whopping 40 m/s. this kind of ruins to point of ever going on the surface, which kind of ruins the fun with submarines. it would be nice if this got fixed, so that craft experience less drag on the surface than underwater.

[Little_fish626]

I think that the issue may be that when you're above water, some of your propeller(s) are above water? If this is the case, consider lowering it/them.

[Nitty_Gritty1]

Also, naturally, any aspirated engine will decrease as the air intakes go below water. I assume this is with electric engines? What you are describing is not a natural behavior. I've built a few uboats before, all of them go faster when on the surface, and when on diesel power.

[GrumpyOldMan]

The game is rather authentic, simulating waves acting on the hull even if you get no visual bow waves / wake. Go out in the open with a boat, jump in the water next to it and turn up wind and observe how the waves move you around relative to your boat.

This also acts on the boat when moving around and slowly fades the more you submerge.

Around 10-20m below the surface your speed will increase significantly at the same throttle value, due to no waves acting upon your hull.

[Booze_Rooster]

I wouldn't say the game is broken- it has to do with your build. If something is overperforming, dial it back. Limit the throttles, change gearbox ratios etc.

You also need to account for the fact that electric motors in submarines aren't made for speed. They're set up to run quietly for long periods. This typically limits the speed of a vessel they're powering, versus mounting the motors solidly to the hull and running them as fast as they can go. Sure, you'll crank up the knots but your motors will run hot and you'll drain your batteries in minutes, not hours.

I say dial back your throttle and clutch settings until its as slow as you feel it should be for your build. Congratulate yourself that you exceeded design expectations on the first go-round.

[Mike]

I've also noticed this. I think the drag is reduced significantly for fully submerged vessels. This mimic modern submarines which are much faster submerged than surfaced. The old WWII boats had very draggy topsides so went much slower when submerged.

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Originally posted by Little_fish626:

I think that the issue may be that when you're above water, some of your propeller(s) are above water? If this is the case, consider lowering it/them.

the porpellers are fully submereged even on the surface.

[[spacebar]]

Originally posted by GrumpyOldMan:

The game is rather authentic, simulating waves acting on the hull even if you get no visual bow waves / wake. Go out in the open with a boat, jump in the water next to it and turn up wind and observe how the waves move you around relative to your boat.

This also acts on the boat when moving around and slowly fades the more you submerge.

Around 10-20m below the surface your speed will increase significantly at the same throttle value, due to no waves acting upon your hull.

i tested the speed with waves at 0% and the speed was still slower underwater. no waves were affecting the submarine.

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Originally posted by Booze_Rooster:

I wouldn't say the game is broken- it has to do with your build. If something is overperforming, dial it back. Limit the throttles, change gearbox ratios etc.

You also need to account for the fact that electric motors in submarines aren't made for speed. They're set up to run quietly for long periods. This typically limits the speed of a vessel they're powering, versus mounting the motors solidly to the hull and running them as fast as they can go. Sure, you'll crank up the knots but your motors will run hot and you'll drain your batteries in minutes, not hours.

I say dial back your throttle and clutch settings until its as slow as you feel it should be for your build. Congratulate yourself that you exceeded design expectations on the first go-round.

i understand this but it still doesn't explain why it goes faster underwater. i don't change the throttle setting from above vs. below the surface, and there's nothing fighting the vessel on the surface.

[Aven]

Originally posted by #000fff spacebar:

i understand this but it still doesn't explain why it goes faster underwater. i don't change the throttle setting from above vs. below the surface, and there's nothing fighting the vessel on the surface.

Because that's how it's supposed to be. In both the real world and Stormworks, submersibles are faster underwater. Even swimmers are faster underwater, however the issue is that a swimmer creates drag the second they use their arms.

[Ronald "Billium" Reagan]

So in short there are two possible options, and ive noticed this too.
1, stormworks has a drag function that changes the deeper you get. In all likelihood this is probably to mimic how submerged vessels don't deal with nearly as much surface drag or current.
2, Stormworks is applying the Air and Water drag to your vessel when not submerged. This could answer it but it doesn't seem to be the case for my nuclear subs which sit barely above the surface.

Seems like the deeper you go the less drag you feel to a point, which is somewhat realistic

[Booze_Rooster]

I bet you the game have a simulated "air resistance" and totally omitted fluid resistance. The way the game calculates mass of sealed area instead of displacement, you're not getting an accurate representation of a vessel's hull in the water anyway. I mean its not like you have to streamline a hull. My first build i was wedging everything, lightening everything, going back and re wedging, re lightening etc. Then I realized my idiot friend could hop on the game and power a 100m cube with jet engines that outran any realistic boat I built.