2 Distinct Surface Depths(howto)

[-Pv-]

Surface stealth modes...

I have tested two reliable and repeatable surface depths that leave battery charge and surface engines enabled. These have been tested on Porpoise, Sarg, and Salmon (all 246 ft test depth boats) with average 16 ft full-surfaced depths.

Command 22 ft:
Verbal Feedback "25 ft"
Text Feedback "25 ft"
Drag AND Hold the cursor arrow exactly over the 25ft mark and let go.
Result:
Average 22 ft depth. All surface crew stations and guns are enabled and water flows over the rear deck about 10% of the time( in average conditions.) Speed remains normal.
Diving time is reduced about 5 seconds. A peculiar behavior of this mode is it's so close to the depth set to activate the dive planes that they continuously animate.

Command 28ft:
Verbal Feedback "28 ft"
Text Feedback "28 ft"
Drag AND Hold the cursor arrow over the area between 25 and 30 ft and let go.
Result:
Average 24 ft depth. Crew will remain on deck untill a wave causes a large depth excursion then will leave. Bridge remains accessible to the user. Deck gun is totally disabled. Rear AA gun remains player accessible, but not command accessible. It may blink off on large waves. If you have two AA guns, the foward gun may be disabled. Water covers the rear deck about 90% of the time and forward deck about 50% of the time. Speed is reduced about 3-4 knots. Sail is submerged in about 10 seconds on diving. This mode produces a lot of wave sloshing sound effect which gets muted when using time compression.

These techniques were highly valuable for getting the most of your surface engines in SH3 while getting close to the target and maximizing your battery time while decreasing visibility of your own boat.

Note: If you do not get these specific text and verbal feedback cues when setting the depth (you get 24 on the text and 25 on the verbal for instance) then repeat the procedure until the desired command is echoed exactly in both text and voice.

Note 2: There is a third mode that leaves the bridge accessible to the user with only sail exposed, but electric power is activated. Set the depth to 30 feet exactly. I like to use this mode to get a final 1st person 360 degree perpective on the tactical situation just prior to ordering parascope depth for the final attack run. It's also handy at the last stage tactical observation prior to a surface gun attack. It's also a great torpedo attack profile where you can combine the tactical awareness you get from the bridge with some stealth while sacraficing speed and manuverability. A quick pop-up to surface and you're ready to add guns to the action without changing your view station.

Note 3: Parascope depth command results in 54ft depth and very iffy sonar operation. Only few if any sonar contacts get enabled. Command a depth of 55 feet exactly and you will get full sonar functionality and the attack scope is still exposed enough to see over the smaller waves. You can test the effectiveness of the sonar by rotating it to 180 and listen for your props. If you don't hear them, go a foot lower.

Note 4 for newbies: You do not have to use the set engine commands. Change the engine telegraph to show knots and drag the cursor arrow to the exact speed you want to hold.
When you need to preserve battery life and increase stealth over speed, set speed to 2 knots for good manuverability (you need to set 1 pixel over for the voice and text to echo your choice accurately) and you will double your submerged battery life over "Ahead 1/3." 2 knots is perfect for those day transits through areas heavily patrolled by planes. You make good progress, increase your surface fuel duration, and can stay under with reasonably low surface recharge time for an entire daylight period.
Set to 1 knot (one pixel over) and you can stay submerged for close to a day or more. Stealth is increased at the cost of almost no turn rate. This mode pays off well when trying to evade ships hunting you close by but have not pinged you yet at the cost of player patience. If you start getting pinged rapidly, change depth and or increase speed and direction. 1 knot during an attack run right over head is sure death.
One knot is the minimum speed necessary to hold or change depth without using air pressure reserves. Of course the stealthiest mode is all stop, but over time crew will struggle to hold assigned depth and lose the battle slowly.
Only use stopif you are in a position not likely to be found and you just want to wait them out with little possibility of alerting them to your presence.
You CANNOT use this technique for reversed speeds. The speed will get set to foward if you do.

-Pv-

[OneTinSoldier]

Very informative and interesting -Pv-. Looks like you spent a fair amount of time investigating the stealth phenomenon, and typing it in!

It sounds to me like this is something that is somewhat of an improvement over SH3!

And yep, two knots is the way to go for underwater endurance, excellent tip there and description on how to set it.

[Egan]

The last two 'decks awash' depths will be very useful for crash dives in hot waters, but I wonder how much they affect the Ai sensors and ability to see us.

[9th_cow]

this is something i discovered a while ago, someone here was asking if going "decks awash" was possible and i had a look for them.
my results were the same as yours for "result 2" only the tower above the water. and the AA operatable ( only tested with rear fitting)

i did discover in testing that this lets the enemy spot you at the exact same distance as going in fully surfaced however.
but there is a huge ( was pre patch) benefit to crash diving. it reduces the time immensly ( again not tested since patching)
anyways since patching ive never gotten the sub back into that mode. never could work out how many feet 7 metres was

ill have to give the rest of your settings a try though, if nothing else its a nice effect in calm seas seeing your sub scooting along with only the tower above the water line.

[Tigrone]

7 meters at 3.3 to one = 23 feet

[-Pv-]

To replicate my settings in meters, try 8 (7.6 meters rounded up) for the shallow wash and 9 (8.5 rounded up) for the level two.

When using 1.1 I have been in procimity to aircraft that would have spotted me if I had been fully surfaced.

In the sub school convoy attack, I had trouble keeping from getting spotted immediately by the lead escort until I used level two while reversing slowly until I was awash, then I moved foward a while then dived. Own speed also has a very great influence on enemy spotting.
-Pv-

[JackChen]

Nice tricks there on the depths, kinda like snorkeling.

Supposed to reduce your visibility to flushed against the waves.

Good for quick dives, my friend has been complaining on the diving speed.