XXI tactics

[AngusJS]

If you cruise submerged at a respectable speed, how can you hear contacts? And if you cruise surfaced, won't planes or HK groups get you?

What tactics do you use? It would be useful to know, in the unlikely event that I ever get to that point in my career.

[Torplexed]

I don't know if it was changed in to the mods, but the game as is doesn't model the fact that the din of cruising at high speed submerged with the diesels on should render the hydrophone operator deaf. You can pick up sound bearings at any speed while using a snorkel. You can also go unrealistically fast underwater with a snorkel even in a non Type XXI.

[danlisa]

As with any U-Boat, it's best to conduct stationary (silent) sound checks. The same is true for the Type 21.

The 21 was designed for extended spells submerged, to avoid Aircraft and HK patrols, however, to enable yourself to hear sound contacts, I'd suggest 40m depth and 5kts (XXI only).

Think about using the 21 as a hit & run boat. Locate your target, attack quickly BUT escape/evade quicker.

Also, if your 21 is fully pimped, don't be affraid to spend some time surfaced as you should get adequate warning via radar of any approaching contacts (use high TC at your own risk).

[Paajtor]

If you're in an area with high enemy aircraft-traffic, then I suggest you travel decks-awash.
Especially the XXI will sail beautifully that way, and will actually pick up another 1 or 2 kts, because of it's great streamline.
Try 9m, during a light breeze...in heavier seas, try 8.5 or 8m.
This way, you can dive much faster, in case of an alarm...plus that you have a smaller radar-profile.

Tactics don't differ that much from the other Uboat-types...but there are a few differencies.
Like the max.depth at which you can launch torpedoes: for the XXI, it's 49m!
This is nice to remember, if you are able to purchase the Zaunkönig-II torps, which are acoustic seekers (they need the target to travel at 10kts minimum, to be able to pick up the engine-sound).
That brings up another difference...for the XXI are some very advanced torpedoe-types available, late war.
This off course, brings advanced tactics.
And then there's the fenomenal max.submerged speed...officially, it should be around 17kts...but I often manage to reach 21kts.
So there will be times, where you will care less about stealth, and rely on your high submerged speed, both for attack and evasion > launch a decoy (the latest type is active for 8-10mins), hit ahead-flank, pick up speed, order silent-running, and swift and silently dive away in the deep...

[Jimbuna]

Just one additional tid bit.....if yo wanna play realistically, don't go above 5 knots whilst schnorkelling. In RL it would vibrate and possibly sheer off (especially in a type XXI)

[Hartmann]

Wow ..

a XXI boat is a deadly machine in hands of a skilled commander .

" on 4th May, U-2511 detected a Suffolk class cruiser, HMS Norfolk, with destroyer escort at a long range. She made a text-book approach, closing at high-speed first, then diving deep and passing the destroyer screen at silent-speed. Finally, Schnee had the cruiser in sights 500 meters away with a perfect attacking position inside the destroyer screen and undetected- impossible not miss. U-2511 did not fire but dived deep again, and still undetected returned to base, arriving at Bergen on 5th May 1945.

[U49]

tried and proven against heavy defence with air support

*) frontal position in 45 degree arc of estimated convoy advance
*) submerged low speed, full batt's

*) pass escort screen with deep and creep, wide arc at low speed, narrow arc with high speed (10kts+) or pure blast-your-path-THROUGH-that-destroyer
*) shoot reload shoot cycle through all the valluable target until they are at least stopped

*) go fast and deep for 10 minutes
*) deep and creep until the escorts have run out of ideas, no worry here, you can stay where you are for a whole day and creep away

*) surface, recharge batteries and maybe kill all the stopped ship wrecks if there are some

[Jimbuna]

Originally Posted by Hartmann

Wow ..

a XXI boat is a deadly machine in hands of a skilled commander .

" on 4th May, U-2511 detected a Suffolk class cruiser, HMS Norfolk, with destroyer escort at a long range. She made a text-book approach, closing at high-speed first, then diving deep and passing the destroyer screen at silent-speed. Finally, Schnee had the cruiser in sights 500 meters away with a perfect attacking position inside the destroyer screen and undetected- impossible not miss. U-2511 did not fire but dived deep again, and still undetected returned to base, arriving at Bergen on 5th May 1945.

So why were no eels fired ? :hmm:

[Paajtor]

Because Schnee had received the cease-fire order.
He even talked to some of the Norfolk-crew a few days later, who were stunned by his story.

[silentwayIII]

I use the XXI in 1945 missions only. Its a deep water boat that has to driven very carefully because of its size and lack of maneuverability. In the rare instances when I can find a convoy to attack this boat can truly be lethal.

My tactic for convoys is to slip past the the screening escorts at 30-35 meters, go to periscope depth and fire a full salvo of torpedo's at 3-4 merchants. I then dive to 35-40 meters and head toward the convoy at 7-10 kts while reloading acoustic torpedo's. Once I'm within the confines of the convoy I travel at the convoy's speed, and general heading, and begin targeting merchants with the acoustic torpedo's. I fire to my left, for instance and then move to another location or column of merchants to my right always remaining at 35-40 meters and repeat the process again.

When I'm done...out of torpedo's or things are getting dicey with the escorts, I begin a spiral decent at silent speed with the convoy above me. Decend to 150 meters and then straighten up exit the convoy and continue to 260 + meter.

Again, the big advantage is overal speed and torpedo reload time. Because the silent speed creep motors are not modelled in SHIII the XXI is only as quite as other U-boats.

SilentwayIII's XXI convoy attack tactics 101

[Jimbuna]

Yeah....got a tad confused there for a moment.

Doenitz gave the surrender order to all naval/U-boat vessels on May 4th but the official surrender didn't occur until the 7th

[Paajtor]

Yes, good thing that Dönitz was a man of honour in the end.

And yes, SilentWay...it's a shame that the creep-engines aren't modelled.
Or would it be possible to mod this in?

[Jimbuna]

Originally Posted by Paajtor

Yes, good thing that Dönitz was a man of honour in the end.

And yes, SilentWay...it's a shame that the creep-engines aren't modelled.
Or would it be possible to mod this in?

Too late for GWX....all additional content/changes were closed a little while back.
Perhaps sometime in a future release.....willing hands permitting :hmm:

[Paajtor]

I hope so, JimB.
Now that SH3 is out for several years, people are trying even harder to get everything out of the subsim...hence the increasing interest in the XXI as well.
This has become very obvious in the past year, imo.
The tweaking that the GWX-team already did to the model, plus the excellent skins that got released (Fubar's latest XXI-skin is stunning!), make it a very enjoyable ride.

I don't care much, that this Uboat-type wasn't actively used in combat in reality ...after all, everything we do, is a simulation.

[Hartmann]

Model the creep engines could need modify some sensor files because at 6 knts the XXI was in silent running... but perhaps some could done it as a stand alone mod for use only with XXI submarine.