Underwater fireing

[TorpX]

Originally Posted by raoul01

Does somebody know if you can fire torpedoes underwater without using the periscope?

As Platapus said, firing is one thing, hitting is another.


Not sure about the game, but in RL, you would not want to try this too deep. The impulse mechanism wasn't designed for launching from a great depth, and the interior doors of the torpedo tubes could not withstand too much pressure. I think you could launch from 100 to 150 ft. though.

[CapnScurvy]

The trick to firing an accurate torpedo, without using the periscope, is in inputting the relative bearing of the target. If you have the Speed, AoB (which provides the target track or its expected traveled path), and Range, the only part that's missing is inputting the target Bearing.

In the game, the targets relative bearing is inputted along with the range figure when you take a stadimeter reading and "Send" the range to the TDC/Position Keeper. The fact that the periscope is positioned onto the target just to take a stadimeter reading allowed the developers to think "we can put the two inputs together". That's one reason the manual states you should "lock" onto a target before taking a stadimeter reading. Locking onto a target "centers" the periscope on the ship and makes the bearing of the periscope compass the one inputted along with the Range when sent.

Looking at the Position Keeper dials will show you the firing solution as it stands. Judging from them and comparing their setup to any other information you may be using (nav map, radar, sonar) you can make a fairly good guess as to how accurate your firing solution will be.

The sonar will input the target bearing if you specifically "send" it to the TDC/Position Keeper. Use the toggle switch on the far right of the sonar unit to send the bearing. That small notepad at the top left corner is only for the German sonar display. A leftover from the SHIII combining of the two games. Don't use it to send the bearing if you are playing the American side. It doesn't send the bearing to the TDC/Position Keeper for the American side of play. Only the toggle switch that's below the sonar bearing dial does.

But, we all know that making a sonar ping and receiving the data alerts any escorts that may be about to your presence. So, how do you input a bearing without using sonar while being submerged, unable to lock onto the target using the periscope? Go to the periscope station and raise the scope just enough to read the compass bearing. When the scope is retracted the view is black, hiding the relative compass bearing. Raising it up just a bit allows the compass bearing to be visible. Turn the periscope to the desired bearing you choose and "send" the Range/Bearing both at the same time. The proper gyro angle will be shown on the lower sub dial of the PK.

There's only one catch with the above procedure. You'll need to have the Range set as well before sending the input. If you input the correct estimated bearing without knowing a good range figure, the solution will be incorrect. Unless you have the Range dial modded to allow for inputting a figure you choose, or have a separate range dial that allows doing the same thing, just sending an accurate bearing won't be enough. Accurate range is important too. Knowing both are "sent" at the same time requires you to have them modded to allow for manual input when trying to fire a torpedo without the use of the periscope viewing the target, and using the stadimeter for inputing range.

[Loudspeaker]

Unfortunately Werner Sobe's video tutorial on the subject seems to be inactive, but although I never carried out a sonar only attack myself, the theory behind it is fairly simple. Once your sonar operator gets a target, have him repeat the bearing during the attack. He will notify you, if the target is closing or moving away. For obvious reasons we will need the target to be closing.

Once the target is within approximately 4000 yards, we can plot its position on the map using active sonar. Go to sonar station and press 'Range to target'. The range will not be exact, so you will need to press it over and over and try to estimate the average range from your observations. Once you are satisfied with your range estimation, go to the map, start chronometer and make your first plot. Repeat this procedure every 5 minutes or so and try to estimate target course from your observations. After a while you will also be able to estimate target speed using chronometer. Now all requirements are met to set up a firing solution.

Go to periscope and input speed and AoB into the TDC.

Move your sub into a good firing position. When the target is within 2000 yards, your range observations will be more accurate. Just before the attack, go to sonar station and send range and bearing repeatedly to TDC using the buttons on command bar. Launch torpedoes and cross your fingers

[WernherVonTrapp]

Originally Posted by TorpX

As Platapus said, firing is one thing, hitting is another.

"Fireing" underwater is one thing, "firing" underwater is another.

[TorpX]

Ooops, someone broke the strict forum rules about spelling. That's a fine of 1,000 Quatloos.

[Loudspeaker]

Werner Sobe's tutorials:

http://www.myvideo.de/watch/1280661
http://www.myvideo.de/watch/1280691

[PacificWolf]

When you engaging a target without periscope how can identify is he friend or foe?
Especially in bad weather and at moonles night.

[Rockin Robbins]

If you get sent to Leavenworth busting rocks at the end of your patrol the target was probably the USS Essex.......

[I'm goin' down]

Originally Posted by Rockin Robbins

If you get sent to Leavenworth busting rocks at the end of your patrol the target was probably the USS Essex.......

Who could possibly be dumb enough to do that?

[Loudspeaker]

Originally Posted by PacificWolf

When you engaging a target without periscope how can identify is he friend or foe?
Especially in bad weather and at moonles night.

You can't. But you can make a qualified guess depending on where you are. If you are in Japanese home waters, kill whatever you find.

Btw, I have just conducted my first sonar only attack this evening, inspired partly by my own post above and partly on Sobe's videos. And you know what, guys? The sonar only attack is becoming my favourite method, because I think it's easier to determine range by sonar than by stadimeter, once you get the hang of it.

The funny thing is, it shouldn't be like this. The real skippers avoided it, although at the academy they were instructed to attack by sonar only. Raising the periscope endangered your crew and boat each time you did it, just like it does nowadays.

Get to know the sonar-thingy provided to you by the glorious US navy. It's quite addictive

[magic452]

Sonar only shooting can be a whole lot of fun because you really have to concentrate and you get real satisfaction when you hit.

I use Vector Analysis type of a shot and track the target on the nav. map and shoot from there, at about 90 feet deep.

You may not get an Essex but you can always hope.

Magic

[CapnScurvy]

Originally Posted by Loudspeaker

The sonar only attack is becoming my favourite method, because I think it's easier to determine range by sonar than by stadimeter, once you get the hang of it.

The funny thing is, it shouldn't be like this. The real skippers avoided it, although at the academy they were instructed to attack by sonar only. Raising the periscope endangered your crew and boat each time you did it, just like it does nowadays.

Get to know the sonar-thingy provided to you by the glorious US navy. It's quite addictive

The one reason the sonar in-game is better than the stadimeter is it gives exact data to the TDC/Position Keeper when "sent". In reality, the sonar target data gleaned was only as good as the operator who used it. But, in-game by zero'ing in on a target bearing, you'll get an accurate range down to the exact yard. Reality was never that good.

On the other hand, the in-game stadimeter is dependant on several factors to get an accurate "estimate" of range. The Recognition Manual has to have a fairly accurate "height" figure to produce a found range that's close. I took a look at the TMO 2.5 height figures and I see the Hiryu CV still has the mast height at 20 meters. This height figure was in the stock 1.0 version for the Hiryu. At 1200 yards true distance the stadimeter is going to report a range of only 600 yards. Good luck in hitting the Hiryu unless you're so close you'll see the whites of their eye's! Another problem is the way the stadimeter "marks" a height figure. When you draw down the second images waterline to the height reference point, if you strike the mouse just one pixel line adjacent to the exact measured point, the found range can be about 10 yards off (depending on how far away you are from the target). 10 yards off if the target is at a true 1000 yards distance, much more at longer distances (up to 30/40 yards off at 2400 yards or so). Move the waterline off the reference points pixel line more, and you'll increase the error more. Just how wide is a pixel line on the scope screen? There are three pixel lines on each stock Telemeter Division marks. Three lines make up the dark hash marks, from the top side, to the bottom side of the line.

Speaking of the Telemeter Division lines, the ability to have the Telemeter Divisions accurately measure a target was not possible before the Optical Targeting Correction mod. With the scopes providing an accurate field-of-view, and the telemeter divisions scaled to read that FoV, the gamer can use the scope to find range as they did in real life. Just another way to figure manual targeting solutions as the real life Captain's did. Actually I've noticed when using the Telemeter Divisions as a measuring tool and calculating the range through the Omnimeter, the range solution is more accurate than the stadimeter (even with a fairly reasonable height dimension). Mainly due to the short comings of the stadimeter as the game has it.