PDA

View Full Version : DECKS AWASH



sneakattacks
05-16-2009, 11:17 PM
DECKS AWASH (DA), as used here, means to operate at the deepest depth that the diesels will run continuously . The advantage in doing this is that, when compared to being fully surfaced, much less time is needed to disappear below the waves. If a threat appears, go to DA early and avoid being pounded (or sunk) as you wait, and wait, and wait, to submerge.

Running DA is mainly useful to avoid air threats. If battery recharging is critical and aircraft might be near you can safely recharge until the aircraft are spotted before quickly diving. Or, if you have radar, you can surface to DA and check for enemy aircraft before coming completely up with the comfort that if aircraft are present, they can still be avoided with a quick dive. With practice you will find other times DA is a lifesaver (rescuing downed airmen with enemy guns nearby, etc).

Two important points must be remembered, to use DA successfully. First, the critical depth for running at DA is often different between classes of submarine. Second, the critical depth for the diesels is usually deeper than that for CO2/O2 exchange and using the deck gun. This means CO2 can build up inside the sub. So there is a second DA to remember, DA(CO2). It, too, varies between sub classes but as a rule, it's 2-3 feet less than DA (diesel). DA(CO2) is always the same as the critical depth for using the deck gun, or DA(Gun), so the two can be combined.

Below is a guideline which lists the critical depths for DA(diesel) and DA(CO2/Gun) for the different classes of sub in SH4. [Measurements were made at flank speed, in calm seas, with 100% battery charge.]

DECKS AWASH DEPTH IN FEET FOR SUB TYPES

TYPE BOAT.........DA(diesel)........DA(CO2/GUN)
GATO.....................28...................26
BALAO....................28...................26
GAR.......................32...................26
PORPOISE...............28...................23
SALMON.................31...................26
NARWHAL...............30...................28
TAMBOR.................33...................25
SARGO...................31...................28
S-42......................26...................26
S-18......................26...................26

As a rule, 28 feet is a good rough guide for DA(diesel) (unless you're in an "S" boat or "TAMBOR", where it's 25 to 26). "SALMON", and "NARWHAL" classes can run slightly deeper (about 30). "GAR" and "TAMBOR" can do 32 feet.

For DA(CO2/Gun), 26 feet is a good guide for getting rid of CO2 for all boats except the "PORPOISE" class, where you must be at 23 feet, and the "NARWHAL", "TAMBOR", and "SARGO" classes, where it's 28.

The time needed to reach periscope depth is affected by 1) the depth at which the "dive" order is given, 2) the dive depth ordered ("periscope depth" vs "CRASH DIVE!"). "CRASH DIVE!" is always faster. But to avoid suicide, remember that ordering "CRASH DIVE!" takes you to 160 feet. Without that much water under you, you will die, unless you can successfully change the order (after submerging) before hitting bottom. Use "CRASH DIVE!" with caution.

Below are dive times (in seconds) between classes of boats for the order "periscope depth", fully surfaced and at DA(diesel). Times to reach periscope depth on ordering "CRASH DIVE!" will be faster. [Times were obtained at flank speed, in calm seas, with 100% battery charge.]

TIME TO REACH PERISCOPE DEPTH

TYPE BOAT......SURFACED............DA(diesel)
GATO..................120.....................23
BALAO..................80.....................29
GAR....................120.....................23
PORPOISE.............85.....................24
SALMON..............107.....................26
NARWHAL............125.....................24
TAMBOR...............123....................26
SARGO.................123....................24
S-42....................72.....................47
S-18....................72.....................47

The difference between dive times is dramatic, and clearly shows the advantage of running at decks awash when a fast dive is important. It should be remembered that the DA strategy for recharging doesn't work in rough seas, where the electric engines will cut on and off, discharging the batteries.

Also remember that you get poor fuel efficiency (fewer MPG) and lower speed when running at Decks Awash since you are, after all, partly submerged.

(Incidentally, "CRASH DIVE!" from DA(diesel) will reach periscope depth for all boat classes in 17 seconds, except the "TAMBOR" class which makes it in just 15. Now that's a fast dive!)

Practical Tips:
To get to a specific depth, use the shallow depth meter (the one with the red needle at periscope depth), put the point of the cursor over the where tick mark should be for the desired depth, and left click the mouse. The "new depth" order will appear in the notification window at top of screen. (A voice will state the "new depth" order too, but often it isn't the same depth as you see printed in the window. ALWAYS go by what's in the window.) You may find the "new depth" you see ordered is not the one you thought you clicked on. If so, just do it again, this time pointing the cursor a tiny bit deeper/shallower on the depth meter from before, and notice the result. Keep doing this in tiny changes until you get the feel of it. Once you do, you should be able to "dial in" 26 feet and get it, or at least within a foot either way.

Again, to successfully run at Decks Awash you must have a sea-state that allows you to maintain constant depth, since you're running the diesels at (or near) the lowest depth they can get air. Boat speed also affects depth control. Faster is steadier.

Overall, it's probably safer to not push the limit, depth-wise, in using DA as a strategy. Give yourself a margin of error. Dive times should not be much affected.

Use the numbers as a guide and remember, they are based on the depth you see ordered as "new depth" in the notification window (top of screen). The depth seen at the bottom right of the controls (next to the "+" of Time Compression) is usually NOT what you dialed in, neither is the audio "new depth".

Versions:
This study was made using Silent Hunter4 (1.4). The later SH4 (1.5) data may, or not be different, but the concept is the same. Modding to Trigger Maru Overhaul (TMO) does not change the depths for DA, but dive time measurements from full surface ARE faster in TMO. But in all cases, starting from DA gives you a much quicker dive.


NB: The above pertains only to SH4 and does not reflect the performance of historic submarines.

[Strongly recommended: "SH4 Guide" inside "Tips, Mods, Tools, 100K Club," etc. in this Forum]

tuddley3
05-17-2009, 12:22 AM
I really enjoyed this thread, thank you for sharing this info.

Liddabit
05-17-2009, 02:03 AM
Awesome guide thank you, helps me not having to trial and error to find the perfect depths when Ig et a new boat http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

Masterhawk405
05-17-2009, 06:19 AM
Great info to know, thanks http://forums.ubi.com/images/smilies/clap.gif

WernherVonTrapp
05-17-2009, 07:18 AM
I'm impressed. Great work, compiling this statistical info. http://forums.ubi.com/images/smilies/clap.gif This makes things alot easier for the rest of the fleet. http://forums.ubi.com/images/smilies/25.gif How did you manage to calculate all these figures for the different classes of boats? http://forums.ubi.com/groupee_common/emoticons/icon_cool.gif

captgeo
05-17-2009, 07:59 AM
Pppssstt http://forums.ubi.com/images/smilies/10.gif ,You missed the SARGO class http://forums.ubi.com/images/smilies/10.gif http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

dennyc39
05-17-2009, 11:28 AM
Another advantage is that your visibility is considerably reduced, as camera view shows, especially when at DA (diesel).

One problem is that in my Porpoise boat, it is hard to establish 26, 27, or 28 feet as a running depth. The boat seems depth-unstable, and tends to run on up to 22 feet, exposing a lot of deck. After several tries, I can usually get it to settle at 26 or 27 feet. You have to be steady and patient to command the depth gauge within 1 ft. precision.

Range and speed are significantly reduced in this mode, but for periods of a few hours, it still is better than running submerged.

ElAurens
05-17-2009, 11:57 AM
I'm wondering how running one of the mods, like TMO, affects this? I believe that TMO has adjusted the dive times from stock as it is.

realoldephart
05-17-2009, 03:08 PM
I don't know about anyone else but I can't get my boat to even go to 27 or 28 feet it will just stay at 25 ft. I can make it go to 30 but nothing between 25 and 30. Crew responds to command but boat stays at 25. If I am below 30 feet and give command 28 feet boat will go to 25 feet. It ends up neing either 25 or 30 nothing between. Just spent the last hour (actual time trying to accomplisn that to no avail. Boat is a Gato mid 42 running 1.5 TMOwTw and FOTRS ships.
John

sneakattacks
05-17-2009, 06:38 PM
Thanks, everyone, for the feedback, it is most appreciated.

To address some of the issues mentioned:

To get to a specific depth, use the shallow depth meter (the one with the red needle at periscope depth), put the point of the cursor over the where tick mark should be for the desired depth, and left click the mouse. The "new depth" order will appear in the notification window at top of screen. (A voice will state the "new depth" order too, but often it isn't the same depth as you see printed in the window. Always go by what's in the window.) You may find the "new depth" ordered is not the one you clicked on. If so, just do it again, this time pointing the cursor a tiny bit deeper (or shallower) on the depth meter from the first try, and notice the result. Keep doing this in tiny changes until you get the feel of it. Once you do, you should be able to "dial in" 26 feet and get it, or at least within a foot either way.

Again, to successfully run at Decks Awash you must have a sea-state that allows you to maintain constant depth, since you're running the diesels at (or near) the lowest depth they can get air. Boat speed also affects depth control. Faster is steadier.

Overall, it's probably safer to not push the limit, depth-wise, in using DA as a strategy. Give yourself a margin of error. Dive times should not be much affected.

Use the numbers as a guide and remember, they are based on the depth you see ordered as "new depth" in the notification window (top of screen). The depth seen at the bottom right of the controls (next to the "+" of Time Compression) is usually NOT what you dialed in, neither is the audio "new depth".

This study was made using Silent Hunter4 (1.4). SH4 (1.5) data may, or not be different, but the concept is the same. Modding to Trigger Maru Overhaul (TMO) does not change the depths for DA, but dive time measurements from full surface ARE faster in TMO. But in all, starting from DA gives you a much quicker dive.

Expect re-edits as the numbers are rechecked in TMO and SH4 (1.4) and other issues you bring up are looked into.

Thank you again for your helpful comments.

SA

realoldephart
05-17-2009, 10:25 PM
Sneakattacks I would like to know if it's the mods I'm running or what. Calm sea, almost like glass, the depth of 28 feet came up in the window but boat would stay at 25 feet. Or do I just have a rotten crew http://forums.ubi.com/images/smilies/88.gif. I tried for an hour to get that to happen all for nothing as it turned out. I just would not go to 28 ft or 26 or 27 or 29. Tell them 30 respond and go 25 respond and go 28 respond 28 in window boat stays at 25 ft. I just got a promotion and a new boat a Balao if it won't go to 28 it has to be the mod combo I'm running I guess. It sure would be great if it worked though.
John

MWolfe1963
05-18-2009, 09:02 AM
Doe's anyone know how the actual game programs decks awash. I notice when I'm running decks awash enough to run the engines, the ship will eventually surface. If I run awash to where it holds, it goes on electrics, which programs your ship as submerged, thus no crew on deck.

That depth guage sucks. Wish it would somewhat hold on whatever you set it.

sneakattacks
05-18-2009, 07:05 PM
Thank you for your comments. I hope the following addresses these:

the depth of 28 feet came up in the window but boat would stay at 25 feet


Use the numbers as a guide and remember, they are based on the depth you see ordered as "new depth" in the notification window (top of screen). The depth seen at the bottom right of the controls (next to the "+" of Time Compression) is usually NOT what you dialed in, neither is the audio "new depth".
What I'm trying to say is, disregard the depth reading at the bottom right of the screen (when running at Decks Awash). That depth won't be what you saw as the "new depth" order in the notification window (top of screen) and can only mislead you. Only look at the "new depth" order at top of screen to set the desired DA depth and ignore the other. It's a game quirk you have to work around.

Doe's anyone know how the actual game programs decks awash.

The game doesn't program Decks Awash. You have to set your depth where you want to be.

I notice when I'm running decks awash enough to run the engines, the ship will eventually surface. If I run awash to where it holds, it goes on electrics, which programs your ship as submerged


"Decks Awash" (DA), as used here, means to operate at the deepest depth that the diesels will run continuously.
If the electrics come on, you're too deep (or the seas are too rough) to run at DA as the term is used here. Note that this definition does not mention how your boat looks at DA. Please also note that what I describe applies only to SH4 and not the performance of historic submarines.

SA

walkirie
05-19-2009, 09:01 AM
http://forums.ubi.com/images/smilies/25.gif thank you very much for the info http://forums.ubi.com/images/smilies/25.gif

tambor198
05-19-2009, 12:21 PM
I've added the info provided by sneakattacks on Decks Awash to the SHIV Guide. Thanks for your contribution, sneakattacks. http://forums.ubi.com/images/smilies/25.gif

UssSpikefish
05-24-2009, 08:51 AM
Thanks for this idea. I've used it a few times now with good success!!

sneakattacks
05-24-2009, 09:34 PM
Glad it works for you!

BTW, "DECKS AWASH" as seen at the start of this thread is the final edit and is, at this writing, more complete and more accurate than what you'll see in the SH4 Guide at this time. That version will, hopefully, be updated soon.

SA