XXI submerged attacks

Ula Jolly · 06-07-07, 01:30 PM

I love the thought of being able to use the sonar and hydrophone as the only way of attacking. However, are there any good manuals on how to actually attack without ever raising periscope? I see calculating AOB as a distinct problem.
Also, can torpedoes be fired safely from 40-50 meters under the surface? What are their maximum angles of ascent to the surface?

ichso · 06-07-07, 01:41 PM

As I see this, the Fast 90° Method should work for attacking without seeing the target. It is described in detail in Naboos manual targeting tutorial.

With sonar and hydrophone you're able to locate the target's position and mark it on the map, wait the 3:15, do it again, and you get its course and speed. position yourself in front of it, at a good attacking range, heading a 90° course relativ to the target one's. Then you just wait for the ship to get in your 0° line and this will be the exact moment the target has an AoB of 90° on you.
You can easily adapt this method, e.g. if the target will have you starboards (if this is the RIGHT side, just know the german names) and you can turn 10° to the right and wait for the target to get into you 350° line. Analog if you approach the ship from the other side. This little adaption will reduce your gyro angle. How many °'s you need to turn to get a 0° gyro mainly depends on the target's speed.

Edit: About the maximum depth you can fire torpedoes from your XXI I've read something some time ago, dunno where and what though :> Wasn't that something about 50-60 meters ? Really unsure about this, better not trust me.

Paajtor · 06-07-07, 02:49 PM

In GWX1.03...around 49m.

Morts · 06-07-07, 02:55 PM

i can do a submerged attack without the use of periscope
as long as i have a sonar so i can ping for the range
its as quick as using the regular manual method (with periscope)

scrag · 06-07-07, 05:12 PM

Acoustic Homing torpedos or use the Fat in a ladder search - how hardest thing to ascertain is range. You can get that by watching the length of passive contact - get a feel for the transition oa usable solution. Next you need to watch the bearing drift - or which way the target is heading by how the bearings change. you need to drive the boat such that you can control that rate or drift - you will come up with a speed and a direction when sonar indicates the merchie is on constant range. your speed is close and your heading is close zig zag is no problem if you look at the big scheme of where he is going and if it makes sense - make the appropriate offsets and size for the FAT and shoot the weapon.

joegrundman · 06-07-07, 07:31 PM

I wrote a tutorial on submerged approaches here:

http://www.subsim.com/radioroom/showthread.php?t=115366

You still need pings or observation for an accurate range before firing but the approach can be conducted using hydrophones only. It also provides an effective way of estimating AOB.

It works best if you have made either the american SACF whiz wheel or the german equivalent

jmr · 06-08-07, 12:02 AM

Here's another tutorial detailing how you can attack using only your hydrophones

http://www.subsim.com/radioroom/showthread.php?t=110619

ichso · 06-08-07, 12:32 AM

Didn't play that much in the late war period yet. Wheren't you able to use your active sonar (if equipped) to get a range value to your target ? This would eliminate the whole problem of marking a contact's position.

06-07-07, 01:30 PM	#1
Ula Jolly Samurai Navy Join Date: Jun 2005 Location: Norway Posts: 567 Downloads: 0 Uploads: 0	XXI submerged attacks I love the thought of being able to use the sonar and hydrophone as the only way of attacking. However, are there any good manuals on how to actually attack without ever raising periscope? I see calculating AOB as a distinct problem. Also, can torpedoes be fired safely from 40-50 meters under the surface? What are their maximum angles of ascent to the surface? __________________ I shall punish yee, landlubber! C'mere for spankings and popsicles!

06-07-07, 01:41 PM	#2
ichso Ace of the Deep Join Date: Jul 2005 Location: Germany's oldest city alive Posts: 1,066 Downloads: 57 Uploads: 0	As I see this, the Fast 90° Method should work for attacking without seeing the target. It is described in detail in Naboos manual targeting tutorial. With sonar and hydrophone you're able to locate the target's position and mark it on the map, wait the 3:15, do it again, and you get its course and speed. position yourself in front of it, at a good attacking range, heading a 90° course relativ to the target one's. Then you just wait for the ship to get in your 0° line and this will be the exact moment the target has an AoB of 90° on you. You can easily adapt this method, e.g. if the target will have you starboards (if this is the RIGHT side, just know the german names) and you can turn 10° to the right and wait for the target to get into you 350° line. Analog if you approach the ship from the other side. This little adaption will reduce your gyro angle. How many °'s you need to turn to get a 0° gyro mainly depends on the target's speed. Edit: About the maximum depth you can fire torpedoes from your XXI I've read something some time ago, dunno where and what though :> Wasn't that something about 50-60 meters ? Really unsure about this, better not trust me. Last edited by ichso; 06-07-07 at 02:28 PM.

06-07-07, 02:49 PM	#3
Paajtor The Old Man Join Date: Apr 2005 Location: The Dutch mountains Posts: 1,551 Downloads: 64 Uploads: 1	In GWX1.03...around 49m. __________________

06-07-07, 05:12 PM	#5
scrag Medic Join Date: Dec 2006 Location: Pearl Harbor, Hawaii Posts: 161 Downloads: 6 Uploads: 0	All you need is.. Acoustic Homing torpedos or use the Fat in a ladder search - how hardest thing to ascertain is range. You can get that by watching the length of passive contact - get a feel for the transition oa usable solution. Next you need to watch the bearing drift - or which way the target is heading by how the bearings change. you need to drive the boat such that you can control that rate or drift - you will come up with a speed and a direction when sonar indicates the merchie is on constant range. your speed is close and your heading is close zig zag is no problem if you look at the big scheme of where he is going and if it makes sense - make the appropriate offsets and size for the FAT and shoot the weapon. __________________

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06-07-07, 02:55 PM	#4
Morts Admiral Join Date: Sep 2006 Location: Denmark Posts: 2,395 Downloads: 23 Uploads: 0	i can do a submerged attack without the use of periscope as long as i have a sonar so i can ping for the range its as quick as using the regular manual method (with periscope)

06-07-07, 07:31 PM	#6
joegrundman Ocean Warrior Join Date: May 2007 Posts: 2,689 Downloads: 34 Uploads: 0	I wrote a tutorial on submerged approaches here: http://www.subsim.com/radioroom/showthread.php?t=115366 You still need pings or observation for an accurate range before firing but the approach can be conducted using hydrophones only. It also provides an effective way of estimating AOB. It works best if you have made either the american SACF whiz wheel or the german equivalent

06-08-07, 12:02 AM	#7
jmr Commander Join Date: Sep 2004 Posts: 462 Downloads: 62 Uploads: 0	Here's another tutorial detailing how you can attack using only your hydrophones http://www.subsim.com/radioroom/showthread.php?t=110619

06-08-07, 12:32 AM	#8
ichso Ace of the Deep Join Date: Jul 2005 Location: Germany's oldest city alive Posts: 1,066 Downloads: 57 Uploads: 0	Didn't play that much in the late war period yet. Wheren't you able to use your active sonar (if equipped) to get a range value to your target ? This would eliminate the whole problem of marking a contact's position.