Dive time in v1.3 screwy?

Tobus · 07-19-07, 02:03 AM

I noticed yesterday that my Tambor dives better when lying still (0 kts) then when under speed. This seems strange to me, since when diving under speed uses the diveplanes, where as diving at zero speed only utilizes the ballasttanks.

Did a timing with my tambor (calm weather) from surface to PD:
speed = 0kts: 25 seconds
speed = 9 kts: 38 seconds

Shouldn't this at least be the other way around?

chopped50ford · 07-19-07, 02:23 AM

IT should be...the momentum of the ship and diving planes forcing the ship downward should make it dive quicker.

I would be curious to see what the response is on this one.

Suicide Charlie · 07-19-07, 02:38 AM

When I first started looking at the SHIV side of these forums I was browsing through the screenshot thread a lot. I noticed a large amount of shots showing the downing of aircraft. In SHIII, I almost ALWAYS dove as soon as I spotted aircraft as did most other players that shared their stories.

When I finally got SHIV I figured out why. The subs dive terribly slow, even when crash diving. It like your only choice is to stay up and fight instead of rendering yourself so defenseless as you wait for your boat to sink below the waves.

hyperion2206 · 07-19-07, 03:38 AM

Quote:

Originally Posted by Suicide Charlie

When I first started looking at the SHIV side of these forums I was browsing through the screenshot thread a lot. I noticed a large amount of shots showing the downing of aircraft. In SHIII, I almost ALWAYS dove as soon as I spotted aircraft as did most other players that shared their stories.

When I finally got SHIV I figured out why. The subs dive terribly slow, even when crash diving. It like your only choice is to stay up and fight instead of rendering yourself so defenseless as you wait for your boat to sink below the waves.

This was true until patch 1.3 was released. Now you always get a warning when aircrafts are near you giving you plenty of time to crash dive.

Suicide Charlie · 07-19-07, 05:03 AM

Radar warning, yes. You're usually able to dive before they get on scene and in a bombing run.

joea · 07-19-07, 05:59 AM

US subs did take longer to dive but how long? Compared to U-boats?

nomad_delta · 07-20-07, 04:48 AM

Ok, I've run some tests, and here's the data I've come up with so far. All tests were performed on a clean install of SH4 1.3 with no mods applied. All timing was done w/ a real stopwatch (not the one in the game) and no time compression. All commands were issued via the keyboard shortcuts, not by clicking on the depth meter. So here's the data:

Here's where it gets really interesting: you'll notice in the chart there I have some of the dive times marked as "DRY" and some marked as "WET". There may be a proper term for this that I'm unaware of, but in my chart "DRY" specifies that the submarine has been surfaced for at least 20 minutes, while "WET" specifies that the submarine has been underwater very recently -- within the last couple of minutes.

You can see in the chart there that DRY vs WET makes a huge difference in overall dive times.

It took me quite a while to figure out what was happening, but it appears that it takes approximately 20 minutes for the water to "drain" out of the limber holes in your sub after you surface. You can actually watch the water draining out of the sides of the sub -- it will stop completely after about 20 minutes. If you dive again before 20 minutes is up, you'll be able to dive much faster than you would otherwise. It's not an on/off thing, either -- there's a gradual progression between the WET/DRY dive times I show in the chart during that 20 minutes.

---

I don't have enough time to write up a detailed analysis of the dive times and speeds right now, but at first glance it appears that Tobus is right -- something is screwy, even once we have the 'wet' vs. 'dry' thing accounted for.

What's odd is that it's not consistent: the 'dry' normal dive times look right with Flank being faster than Stop, while the 'dry' crash dive times are about the same for Flank and Stop.

The 'wet' dive times are what really don't make any sense. Here we're seeing exactly what Tobus was talking about: both subs dive faster at "All Stop" than they do at "Flank" speed.

Another interesting thing I've learned from this is that there really is a difference between "Crash Dive" and normal "Dive" that goes beyond the fact that "Crash Dive" rings up Flank for you. Same goes for "Emergency Surface" as opposed to normal "Surface" -- definitely faster.

----

I plan on collecting the same data for the remaining subs and I'll update the chart once I'm done; should be pretty interesting, I think.

nomad_delta

(edit - almost forgot something else I found that's probably important: I tried all of the above tests both a Battle Stations and not, and saw no significant difference between dive or surface times at all!)

Tobus · 07-20-07, 05:13 AM

WOW, that's one great test!

Screwy kind of physics the dev's have used on this one.

FooFighters · 07-20-07, 05:39 AM

Wow.. this is really getting interesting..
Strange diving times devs

kv29 · 07-20-07, 05:49 AM

people here never cease to amaze me, flaws can´t hide anywhere

are the involved numbers tweakable?

SteamWake · 07-20-07, 09:38 AM

It has been known for some time that if there is a short period of time between dives you will dive faster.

The assumptioin is that there is still 'water' in the ballast tanks so they dont have to 'fill' all the way.

The dive planes evidently are just eye candy. In the previous versions they dident even come down half the time and had no effect on dive times. Unfortunate but true.

The 'data' chart above is about what I expected to see.

You want to see some really diverse results throw a sugar boat into that data.

nomad_delta · 07-20-07, 10:10 AM

Quote:

Originally Posted by kv29

people here never cease to amaze me, flaws can´t hide anywhere

are the involved numbers tweakable?

As soon as I'm done testing, I'm going to find out. :p

nomad_delta

07-19-07, 02:03 AM	#1
Tobus Lieutenant Join Date: Jun 2005 Posts: 260 Downloads: 13 Uploads: 0	Dive time in v1.3 screwy? I noticed yesterday that my Tambor dives better when lying still (0 kts) then when under speed. This seems strange to me, since when diving under speed uses the diveplanes, where as diving at zero speed only utilizes the ballasttanks. Did a timing with my tambor (calm weather) from surface to PD: speed = 0kts: 25 seconds speed = 9 kts: 38 seconds Shouldn't this at least be the other way around?

07-19-07, 02:23 AM	#2
chopped50ford Weps Join Date: Jul 2007 Location: Bentonville, AR Posts: 367 Downloads: 22 Uploads: 0	IT should be...the momentum of the ship and diving planes forcing the ship downward should make it dive quicker. I would be curious to see what the response is on this one. __________________ TM2(SS) USS Asheville - Plankowner, Shellback, "Order of the Ditch" http://ths-i.com/

07-19-07, 02:38 AM	#3
Suicide Charlie Wild Night in Bangkok Join Date: Mar 2006 Location: San Diego, CA Posts: 179 Downloads: 0 Uploads: 0	When I first started looking at the SHIV side of these forums I was browsing through the screenshot thread a lot. I noticed a large amount of shots showing the downing of aircraft. In SHIII, I almost ALWAYS dove as soon as I spotted aircraft as did most other players that shared their stories. When I finally got SHIV I figured out why. The subs dive terribly slow, even when crash diving. It like your only choice is to stay up and fight instead of rendering yourself so defenseless as you wait for your boat to sink below the waves. __________________

07-19-07, 05:03 AM	#5
Suicide Charlie Wild Night in Bangkok Join Date: Mar 2006 Location: San Diego, CA Posts: 179 Downloads: 0 Uploads: 0	Radar warning, yes. You're usually able to dive before they get on scene and in a bombing run. __________________

07-20-07, 04:48 AM	#7
nomad_delta Planesman Join Date: May 2007 Location: San Francisco, California Posts: 185 Downloads: 1 Uploads: 0	Ok, I've run some tests, and here's the data I've come up with so far. All tests were performed on a clean install of SH4 1.3 with no mods applied. All timing was done w/ a real stopwatch (not the one in the game) and no time compression. All commands were issued via the keyboard shortcuts, not by clicking on the depth meter. So here's the data: Here's where it gets really interesting: you'll notice in the chart there I have some of the dive times marked as "DRY" and some marked as "WET". There may be a proper term for this that I'm unaware of, but in my chart "DRY" specifies that the submarine has been surfaced for at least 20 minutes, while "WET" specifies that the submarine has been underwater very recently -- within the last couple of minutes. You can see in the chart there that DRY vs WET makes a huge difference in overall dive times. It took me quite a while to figure out what was happening, but it appears that it takes approximately 20 minutes for the water to "drain" out of the limber holes in your sub after you surface. You can actually watch the water draining out of the sides of the sub -- it will stop completely after about 20 minutes. If you dive again before 20 minutes is up, you'll be able to dive much faster than you would otherwise. It's not an on/off thing, either -- there's a gradual progression between the WET/DRY dive times I show in the chart during that 20 minutes. --- I don't have enough time to write up a detailed analysis of the dive times and speeds right now, but at first glance it appears that Tobus is right -- something is screwy, even once we have the 'wet' vs. 'dry' thing accounted for. What's odd is that it's not consistent: the 'dry' normal dive times look right with Flank being faster than Stop, while the 'dry' crash dive times are about the same for Flank and Stop. The 'wet' dive times are what really don't make any sense. Here we're seeing exactly what Tobus was talking about: both subs dive faster at "All Stop" than they do at "Flank" speed. Another interesting thing I've learned from this is that there really is a difference between "Crash Dive" and normal "Dive" that goes beyond the fact that "Crash Dive" rings up Flank for you. Same goes for "Emergency Surface" as opposed to normal "Surface" -- definitely faster. ---- I plan on collecting the same data for the remaining subs and I'll update the chart once I'm done; should be pretty interesting, I think. nomad_delta (edit - almost forgot something else I found that's probably important: I tried all of the above tests both a Battle Stations and not, and saw no significant difference between dive or surface times at all!) Last edited by nomad_delta; 07-20-07 at 04:58 AM.

07-19-07, 05:59 AM	#6
joea Silent Hunter Join Date: Jul 2002 Location: At periscope depth in Lake Geneva Posts: 3,512 Downloads: 25 Uploads: 0	US subs did take longer to dive but how long? Compared to U-boats?

07-20-07, 05:13 AM	#8
Tobus Lieutenant Join Date: Jun 2005 Posts: 260 Downloads: 13 Uploads: 0	WOW, that's one great test! Screwy kind of physics the dev's have used on this one.

07-20-07, 05:39 AM	#9
FooFighters Grey Wolf Join Date: Oct 2005 Location: The Netherlands Posts: 813 Downloads: 16 Uploads: 0	Wow.. this is really getting interesting.. Strange diving times devs __________________ This forum is not the same without you Dave.. we'll miss you buddy

07-20-07, 05:49 AM	#10
kv29 Watch Officer Join Date: May 2007 Location: Buenos Aires Posts: 342 Downloads: 2 Uploads: 0	people here never cease to amaze me, flaws can´t hide anywhere are the involved numbers tweakable?

07-20-07, 09:38 AM	#11
SteamWake Rear Admiral Join Date: Mar 2005 Posts: 13,224 Downloads: 5 Uploads: 0	It has been known for some time that if there is a short period of time between dives you will dive faster. The assumptioin is that there is still 'water' in the ballast tanks so they dont have to 'fill' all the way. The dive planes evidently are just eye candy. In the previous versions they dident even come down half the time and had no effect on dive times. Unfortunate but true. The 'data' chart above is about what I expected to see. You want to see some really diverse results throw a sugar boat into that data.