Sub Skipper's Bag of Tricks

[Rockin Robbins]

I doubt it. Sonar ranges are not exact. You have to take several readings and kind of average them by gut feeling. Of course, while you are taking the ranges, the range is changing, adding to the challenge.

Sonar only can never be as accurate as periscope guided and radar guided attacks. And we've got it easy! Our sonar bearings are exact, where on the real boats there was a 2º slop factor where it was impossible to perfectly center the sonar bearing. I'm unclear whether that was plus or minus two degrees or two degrees total error. It doesn't matter. It means sonar only was more difficult for a real submarine than it is for us.

In the game, make sure your sonar man is following and announcing the target bearing. Put your sonar on that bearing when you ping and don't forget to send bearing and range separately. In the stock game you can use the switches on the panel. For some reason in TMO and RFB you need to use the button bar to send range but can still send bearing from the panel. Be sure you send both to the TDC! I just use the button bar to send both and remove all doubt.

You're right. The sonar only method should never be your default method. It is mostly a demonstration exercise that gives tremendous satisfaction when it works properly. However, in real combat it is VERY useful in heavy fog or rain, where you can get darned close and blast 'em from nowhere.

[Kapitan Soniboy]

Thank you once again. I play TMO since it add so much more fun to the game. I followed every inch of your tutorial and it worked great but I forgot that you were playing the stock game when making the tutorial. However, it worked in the end and it was very fun.

Right now I'm having a Gato in mid 1943 but I find destroyer escorts too easy to evade. Does Japanese ASW techniques improve later in the war? (last question)

[Rockin Robbins]

OOOOOOOOOOOO YEAH!!! Japanese escorts are nasty, nasty from the last half of 1944 on. I just attacked a nine ship convoy guarded by four assorted escorts in the South China Sea just north of Formosa. It was stormy conditions, so sonar wasn't the greatest, but I only had 150' of water and no thermal barrier to deal with.

Three night attacks over two nights and I never got a shot at the merchies. I did sink my first escort in a surface gun battle (is there any other kind?). I consider that an impressive achievement in TMO. He couldn't hit the broad side of a barn in the rough conditions and I played Jack-in-the box with him. I'd pop up, take four shots or so, submerge and pop up again somewhere else. Between the deck gun and 40mm I finally sank him. Didn't do any good. The remaining three drove me off again. What a battle! 48 hours of pure mayhem.

[Kapitan Soniboy]

That's awesome! I would never challenge a Jap escort to a gun battle! But I did have to blow ballast once since my boat kept sinking after a severe depth charge attack (S-boat of course) and a big gun battle happened on the surface and my little S-boat got pounded in the end... (Now I think it's easier to evade with my Gato)

I raised my SD antenna while at periscope depth and it was able to detect ships (?). I thought the SD radar could only detect aircraft and there is no information about the SD radar on Wikipedia. Do you know anything about it?

[Rockin Robbins]

SD didn't detect anything below a certain number of degrees elevation, so would have had a tough time reporting surface ships. It's a game glitch that we have our radars combined and kind of mashed together.

[DigitalAura]

Originally Posted by Spectator

Setting up the shot: Make sure your boat is properly aligned, so that your bow points at the impact point. What follows now is always the same process, no matter how far you are away from the target (the closer the better in terms of accuracy, therefore i chose ~700yds)

Go to the periscope, make sure your periscope is at 0° and then enter the following data into the TDC:

- AoB = 0 -> send
- Speed = 0 -> send
- Distance = max (turn the distance wheel to the right, should give you about 1200yds in the tdc after you send it) -> send

If I may ask a couple of things regarding this portion of your tutorial, Spec.... I seem to be missing something:

1/ You say you are about 700 yds away, but didn't you just infer that you had to be 4600 yards off because the torpedos range was 4600? (Your cue card for Vector says trace backwards from impact point 4600 yds.)

2/ Why do you enter 1200 yds into the TDC... I mean, why enter anything? From 4600 yds, there is no need to enter any distance.

This worked for me the first time! (Although upon trying again, my torps run out of steam as they hit the boat and usually don't explode....unless I move up to about 4500 yards.)

[magic452]

You just draw your course line 4600 yards from the target track.
You do not have to be 4600 yards away, you can be any were along the your course line (500+ yards) and you just shoot at the angle of the constant bearing line.
If your constant bearing angle is say 10° just point your periscope at 10° Left or right of 0° depending on which direction target is coming from and as the ship crosses the wire you fire.

The instructions you refer to are to clear any old data from the TDC so that the torpedo shoots straight out the front. To do this you must set the periscope to 0° and pull the range all the way down to about 1200 yards. Click the send range button twice to set the gyro angle to 0°

To shoot stern tubes you do the same thing only point the periscope to 180° and sent 1200 yd to the PK.

You must also set speed and AoB to 0 for the same reasons.

If you have good accurate speed and course data this is the most acute and versatile shooting method there is, as far as I'm concerned, and Spectator's tutorial is EXCELLENT.

Magic

[DigitalAura]

ahh... I see, as long as the angles all stay the same, the size of the 'triangle' (including range and target path lines) doesn't even matter.
This is cool! I must try this now that I see it's much easier than I thought.

[TwinStackPete379]

Werner, you magnificent bastard, I WATCHED YOUR VIDEOS!!

[Rockin Robbins]

Yes, hats off in memory of the great WernerSobe, who started the entire manual targeting and targeting school of Silent Hunter 4, right here at Subsim. Werner never returned from his last patrol, but I like to think of him always hunting, always perfecting techniques, always teaching.

Yes, he is gone from Subsim, but he continues to work every day, raising the next generation of manual targeting professionals.

[Frederf]

There's a lot of torpedo targeting already down so I'll see what I can think of apart from that.

Drastically reducing speed and turning 0/180 "slim" to an aircraft contact, radar or visual, is a pretty reliable way to observe it safely while remaining on the surface and get under way again quickly. Keep a finger on that crash dive key in case you're spotted though.

A-scope radar ranges are logarithmic so be careful not to overestimate. 90% of the way between the 5000yd and 10,000yd marks is much closer to 6,000yd indicated than it is to 9,000yd.

Remove the radio_track file from the game's directory and leave the radio on all the time to get instant radio updates for major war events without the silly menu music playing all the time.

The sonar bearing to a contact will generally trail the contact's MoT visual bearing for two reasons: 1. The sound producing part of the contact is the propellers which are located aft of the MoT visual point 2. The speed of sound means that the sound heard currently is associated with where the contact was several seconds ago.

Enemy sensors change behavior under time compression, keep TC use to low values in the presence of escorts.

Keep patrol search pattern turns at right angles or more obtuse to avoid patrolling areas already known to be clear.

Make a habit of depthsounding before diving below periscope depth, especially crash diving.

Count fuel used and time taken on the transit out or calculate how much is needed to get back and add 10%. Write down the date and fuel state you want to leave the patrol area for that 50-70 day endurance and 10% in the tanks as you pull up to the slip.

Use the protractor tool to plot sound contacts based on the width the green light is on making little "crows feet". A history of these on the map helps get a feel for the approach and relative distance.

[Rockin Robbins]

Originally Posted by Frederf

There's a lot of torpedo targeting already down so I'll see what I can think of apart from that.

Drastically reducing speed and turning 0/180 "slim" to an aircraft contact, radar or visual, is a pretty reliable way to observe it safely while remaining on the surface and get under way again quickly. Keep a finger on that crash dive key in case you're spotted though.

And how! Especially important is reducing speed. Why? Because the most visible part of a submarine is the wake! Captain Fluckey used to remain on the surface and reduce speed all the time. Observe the plane. If it approaches to a distance where it could see you, THEN submerge. If you are doing this with radar, there is no reason to crash dive. Just hit D, ahead standard and submerge. If it's a visual sighting and you're doing this hit C and get the heck out of Dodge quickly!

Originally Posted by Frederf

A-scope radar ranges are logarithmic so be careful not to overestimate. 90% of the way between the 5000yd and 10,000rd marks is much closer to 6,000yd indicated than it is to 9,000yd.

A previously unmentioned great gotcha that all who play with map updates off need to take to heart. Great observation!

Originally Posted by Frederf

Remove the radio_track file from the game's directory and leave the radio on all the time to get instant radio updates for major war events.

Enemy sensors change behavior under time compression, keep TC use to low values in the presence of escorts.

Keep patrol search pattern turns at right angles or more obtuse to avoid patrolling areas already known to be clear.

Make a habit of depthsounding before diving below periscope depth, especially crash diving.

Count fuel used and time taken on the transit out or calculate how much is needed to get back and add 10%. Write down the date and fuel state you want to leave the patrol area for that 50-70 endurance and 10% in the tanks as you pull up to the slip.

Use the protractor tool to plot sound contacts based on the width the green light is on making little "crows feet". A history of these on the map helps get a feel for the approach and relative distance.

Great stuff Frederf. Thanks for dropping by and posting this. There is a range at current speed button on the orders bar in RFB and TMO. I don't know about stock.

I've never had a range problem on a single loadout cruise if I kept speed to 9 knots on the surface and stayed up there unless I was absolutely forced to dive. If you get fuel tank damage all warranties are cancelled!

[Frederf]

Oh yeah, the range at current speed button is in stock back to SH3. It's very handy but you have to make sure you're stabilized at speed before you trust it. If you're going 20 kt, order 1 kt, and then immediately press the range at current speed button you'll get 20 kt speed at 1 kt fuel consumption and your navigator will estimate you can sail to the moon with plenty left over.

There's also the issue of getting a very low expected range when recharging batteries since the engines are operating at flank loads for mundane speeds.

Batteries recharge faster as no or slow speeds when surfaced. Engine power going to the screws can't be used to charge.

I've also noticed that the commanded speed and the actual speed aren't one and the same. The command room to-the-0.2-knot dial in front of the helmsman reads different than the GUI dial, usually faster.

Here's a golden tip I almost forgot: Under semi-high TC settings you can check the sea state by how fast the knot-meter wobbles on the GUI. Lots of wobbles means high waves and no wobbles means calm.

Do you know if prop turn counting works in this game or is the sound file static not changing based on merchant speed?

[Rockin Robbins]

Nope, it doesn't work. the game used too few samples and does vary the speed for slow, medium and high speed but not continuously between speeds.

Actually in WWII there were very few targets where speed could be deduced from beat count anyway. They didn't have anything like the modern computer databases that can take a hydrophone input and tell you the name of the ship and how fast it's moving. Most of the Japanese merchant fleet was completely unknown to the Americans. And those that were known were in generally fouled and messy below the waterline, so would run different speeds than they should were they clean and in optimal condition.

For most targets, "speeding up," "slowing down," "running fast," "moving slow," etc, was about as good as you got. We did have some data on a few of the warships.

[Armistead]

RR,

What method do you prefer to use if the convoy is zigging?