XXI -GXW 2.0 Question

[thehiredgun]

Why is there no flak gunns on the XXI in GWX 2.0? My conning tower is just a blank space when I had the XXI. Did someone forget to give them a conning tower?

[Jimbuna]

The flack guns should be there :yep: Did you add them prior to your patrol ? :hmm:

[thehiredgun]

They were not there to add. It would not let me click on them. Is there somewhere I can check in the configuration files for them?

[bigboywooly]

Running any other mods ?

[Erich Topp]

Why snorkeling speed is 21 knot for XXI?

[ref]

Why snorkeling speed is 21 knot for XXI?

Because for the sh3 base code a submarine with a snorkel is equal to a surfaced submarine (speeds talking).

Ref

[Erich Topp]

Because for the sh3 base code a submarine with a snorkel is equal to a surfaced submarine (speeds talking).

Not exactly. Other boats has about 12kt maximal snorkel speed. And in stock game snorkel speed was 16 kts. Not 21. And in GWX it's much more than surface speed. Why? Because some clever man raised diesel engine power in cfg. To make batteries fully charge. All problem is in one thing - XXI electro-engines are more powerful, that diesel ones.
But. In RL XXI project suffered many problems exactly with partial battery charge. One group discharged faster, than other, and this was pretty hard to have all-charged batteries. I read about this in soviet book about XXI boats service in Soviet Navy after the war. That's it - original sim and cfg is much more realistic, than GWX 21-kt runner.

[danlisa]

Why snorkeling speed is 21 knot for XXI?

Why? Because some clever man raised diesel engine power in cfg. To make batteries fully charge.

So when you asked the question, you already knew the answer.

Quit trolling.

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All the snorkelling speeds on all boats are unrealistic for the exact reason Ref stated. If you are playing realistically, you should not be exceeding 5kts on any boat, otherwise the snorkel would break off.

So, it's a matter of having a battery charging fix or keeping an already unrealistic 16kt snorkel speed.

If I was to ever use the XXI, I would want the battery fix, after all the boat is designed to operate submerged.

[Schwuppes]

Why dont you just run at a realisitc 4 knots and wait a bit longer for the batteries to charge?

[Erich Topp]

But in real life forward battery on XXI discharged slower, than aft. I think not-full charge of battery is adequate ingame analog for this. It was not fully tested war-time invention, it definately should have weaknesses and "child issues".

And another question, cannot snorkeling speed be locked down through maxspeed parameter?

Saying this just 'because some people uses 21kt under snorkel as a cheat. 16kt is ok, 'cause it do not exceeds surface of electric-powered speed. But 21kt only on snorkel allows player to have abilities real XXI doesn't have.

[danlisa]

Why dont you just run at a realisitc 4 knots and wait a bit longer for the batteries to charge?

I'm not sure if this was a response to my post.

However, the XXI battery charging fix was not only a correction for the speed at which the batteries charged but also, the bug where the batteries would never reach a full charge, even at high TC, effectively locking the player U-boat at a reduced flank speed while surfaced as only 1 prop was running.

IIRC. Been so long since stock.:rotfl:

[Erich Topp]

effectively locking the player U-boat at a reduced flank speed while surfaced as only 1 prop was running.

Wasn't a big problem to turn on second one by unpressing "charge batteries" button. Actually problem was only in rough seas.

[Schwuppes]

Why dont you just run at a realisitc 4 knots and wait a bit longer for the batteries to charge?

I'm not sure if this was a response to my post.

However, the XXI battery charging fix was not only a correction for the speed at which the batteries charged but also, the bug where the batteries would never reach a full charge, even at high TC, effectively locking the player U-boat at a reduced flank speed while surfaced as only 1 prop was running.



hmmm... that sucks.
So the battery charging fix basically makes you run at 21 knots snorkelling to fully charge the batteries?
Since we have learned from Erich Topp that the XXI actually did have problems with their batteries I want to run GWX2 without the battery fix... how can I disable it?

[Erich Topp]

I am using original .sim file from stock game. It also removes "pitching and rolling" (GWX terms), but not a big problem. If you need this features to stay, use SH3Inspector to change engine power back to SH3 originals, not adjusting mass. Use JSGME for this changes. If you need I can email both .sim to you.

[Schwuppes]

Thanks... I'll have a think about the SH3 inspector.

Btw Erich Topp, do you know if the battery problems reduced the underwater speed and range of the XXI significantly in real life?

[Erich Topp]

Real maximal underwater speed was slightly lower, than announced, but still around 16-17 kts. Interesting, that XXI on full flank speed was more silent, than Gato class on 8 kts. Note, that main electric engines didn't have "silent mount" (as "creep engines", which allowed up to 6 kt speed). German quality))

Another large problem with batteries was their construction. 'cause Lead plates of them was thinner, than on usual MAL/MAK batteries in order to raise capacitance (more plates - more energy). Real time of service for XXI battery was about 1 year (comparing for 3-4 years of VIIC batteries). In war service that's ok, but in peace time this turned in big problems. Also many mechanisms were situated onboard in non-optimal manner... I can give a link to read, but the page is on russian...

[Schwuppes]

may I please have that link?

Maybe I can find a way to translate it, google or babelfish or something. :)

[Erich Topp]

Sure.

http://deepstorm.ru/DeepStorm.files/17-45/for_con/germania/XXI/list.htm

Names, enlighted with blue, is also links to each sub personal page with her "service way". This is very nice source about russian submarine fleet from first subs to nuclears, including foreign projects in russian service.

Btw, found out that project snorkeling speed for XXI is 12 kts. 5 kts limit was only for old-type snorkels on VII and IX, not retractable. Telescopic snorkel on XXI caused less vibrations. But in real life vibrations were to high, when boat went faster, than 10kts. 16 kts is closer to 10, than 21...IMO.

[XXi]

As for the fact of XXI beeing more silent doing 16-17 knots than the Gato:
I`ve read somewhere that XXI was very silent not only due to the engines, actually the propellers of the Type XXI were doing much less noise than these of the previous types, or American subs.
As I`m not a specialist I cannot tell you if it`s true but it does make sense IMHO.

[Jimbuna]

Knot for knot the XXI was quieter.....but I'm not sure about the noise levels at say, for example 16 knots :hmm:

[Erich Topp]

actually the propellers of the Type XXI were doing much less noise than these of the previous types, or American subs.

As written in the sources, hydrodynamic form of XXI was also perfect for keeping silence while moving. A hull, rushing on 16 kts, must cause heavy cavitation, if he isn't hydrodynamically perfect shaped. And less-cavitation screws also could be used.

[difool2]

Knot for knot the XXI was quieter.....but I'm not sure about the noise levels at say, for example 16 knots :hmm:

All I know is that I was unable to shake 2 DDs when running at flank in my XXI-so much for the DDs' hydrophones not working above 15 knots. When I dialed it down to 3 knots I got away easily.

[Erich Topp]

In RL self-cavitation made ASDIC useless on 12kt speed. And you should note, that than speed was higher, that was harder to detect submarine.
In SH3, unfortunately, that not works)

but I'm not sure about the noise levels at say, for example 16 knots

Americans made their tests in 1946, as I know. And also was wondered by this, especially that main electric engines on XXI weren't silenced specially. Remember Schnee approach on British task force on U-2511.

[Jimbuna]

Knot for knot the XXI was quieter.....but I'm not sure about the noise levels at say, for example 16 knots :hmm:

All I know is that I was unable to shake 2 DDs when running at flank in my XXI-so much for the DDs' hydrophones not working above 15 knots. When I dialed it down to 3 knots I got away easily.

Not suprising....one was probably listening whilst the other was directed/guided in. :hmm:

[Kpt. Lehmann]

Because for the sh3 base code a submarine with a snorkel is equal to a surfaced submarine (speeds talking).

Not exactly. Other boats has about 12kt maximal snorkel speed. And in stock game snorkel speed was 16 kts. Not 21. And in GWX it's much more than surface speed. Why? Because some clever man raised diesel engine power in cfg. To make batteries fully charge. All problem is in one thing - XXI electro-engines are more powerful, that diesel ones.
But. In RL XXI project suffered many problems exactly with partial battery charge. One group discharged faster, than other, and this was pretty hard to have all-charged batteries. I read about this in soviet book about XXI boats service in Soviet Navy after the war. That's it - original sim and cfg is much more realistic, than GWX 21-kt runner.

You are incorrect regarding the performance of the Type XXI in-game for the GWX mod. Any user following this thread can test my findings as I did, using the Gibralter single mission and the Type XXI U-boat.

Surfaced maximum flank speed in-game using GWX = 17.2 kts
Submerged on battery power only = 17 kts
Submerged using snorchel = 16 kts
(Note! In real life U-boat commanders while snorkeling, would limit submerged speed to no more than 5 knots due to vibration. Submerged speeds faster than 5 kts could damage or even destroy the snorkel due to hydrodynamic resistance. The code in SH3 does not allow for damage to the snorkel at high speed. Therefore the player must CHOOSE to play realistically if so inclined, by not travelling faster than 5 kts with the snorchel up.

Ref was correct in his explaination here:
Why snorkeling speed is 21 knot for XXI?

Because for the sh3 base code a submarine with a snorkel is equal to a surfaced submarine (speeds talking).
Ref

Given Erich Topp's posting history and attitude problem towards GWX dev team members, it appears to me that the 21 knot snorkel speed he claims to have attained, is not truthful.

Here are my test results using GWX 2.0 without any further modification:

surfaced flank speed
http://i46.photobucket.com/albums/f117/KptLehmann/XXIsurface.jpg

battery power only, flank speed
http://i46.photobucket.com/albums/f117/KptLehmann/XXIbattery.jpg

snorchel up, flank speed
http://i46.photobucket.com/albums/f117/KptLehmann/XXIwsnork.jpg

[Storabrun]

Looks like you forgot to turn on standard propulsion in the last screenshot though. I'm in the summer of 1941 in my new GWX 2.0 campaign so I can't say for sure, but I made 6-7 patrols with a XXI in my old career in GWX 1.3 and a speed of 21 was attainable back then at least. I didn't know how unrealistic that was and used it alot to overtake convoys.

If I understood him right, Erich Topp has sources saying that the XXI was designed for a snorchel speed of 12 knots but in final tests that was lowered to 10 knots because of vibrations. 5-6 knots was for the old non telescopic masts for the VII and IX boats.

That said I'm very much in favour of the changes you have made to get the batteries to charge as they should. If I get that far in my campaign I will just self restrict the speed to 10 knots when snorcheling.

[bertle]

Why dont you just run at a realisitc 4 knots and wait a bit longer for the batteries to charge?
I'm not sure if this was a response to my post.

However, the XXI battery charging fix was not only a correction for the speed at which the batteries charged but also, the bug where the batteries would never reach a full charge, even at high TC, effectively locking the player U-boat at a reduced flank speed while surfaced as only 1 prop was running.


hmmm... that sucks.
So the battery charging fix basically makes you run at 21 knots snorkelling to fully charge the batteries?
Since we have learned from Erich Topp that the XXI actually did have problems with their batteries I want to run GWX2 without the battery fix... how can I disable it?

I hear Erich Topp also thinks pink elephants are about to take over the world.

[Erich Topp]

Kpt. Lehmann, I used GWX 2.0 and 1.03 both, and in both cases snorkeling speed was 21 kts. 16 kts is only when one engine is running. That's not only my opinion. Stop paranoja...think different.

Note! In real life U-boat commanders while snorkeling, would limit submerged speed to no more than 5 knots due to vibration. Submerged speeds faster than 5 kts could damage or even destroy the snorkel due to hydrodynamic resistance.

Only old-style snorchel, which should be raised from deck. Telescopic retractable systems allowed to reach 6 kts on VII/IX and 10 kts on XXI. It also basically depends on depth and weather condition. The deeper boat is (more length of snorchel rohr is underwater), the more vibrations will you have. If there are large waves, it's not reasonable to use schnorchel at all, if you don't want to get asfixed by diesels, sucking air inside the boat.

[Paajtor]

For the XXI in GWX (1.03.... and 2.0 too, I guess. Must test this myself), I think it makes a difference in how you select your max.speed.

- using the preset ahead flank, as Kpt.Lehmann did.

...or

- using the speed-dial needle, and put it on the maximum position, which is somewhere just past 19kts.

By using the last method, I too was able to clock 21kts submerged/schnorkel, in GWX1.03.

[SquareSteelBar]

Given Erich Topp's posting history and attitude problem towards GWX dev team members, it appears to me that the 21 knot snorkel speed he claims to have attained, is not truthful. Maybe it's down-hill speed...http://img116.exs.cx/img116/6469/g5cgrin.gif

[Paajtor]

...in GWX2.0:

http://www.61shap.com/pilots/Paajtor/SHIII/GWX2_XXI_maxspeedschnorkel.jpg

[Kpt. Lehmann]

Pardon an observation here, but the XXI only ran like two war patrols and didn't sink doodly-squat!

I really don't understand the emphasis placed on the XXI with players in SH3... Secondarily, the XXI is the buggiest boat in the game.

<sigh>

[Paajtor]

...as if I didn't know that, lol.:rotfl:

[difool2]

It was buggy, in GWX 2.0 not anymore. Me, I am a student of alternate history and the "What-if?" of an earlier deployment of the XXI intrigues me.

[Sniper_Fox]

i still prefer a VIIC anyday... then again, i havent really gotten past 43 so ill see how well my VIIC and XIB will fair in the british ruled high-seas:arrgh!:

whats the maximum depth of a XXI

[Jimbuna]

i still prefer a VIIC anyday... then again, i havent really gotten past 43 so ill see how well my VIIC and XIB will fair in the british ruled high-seas:arrgh!:

whats the maximum depth of a XXI

In RL 270m......In GWX, you'll find that out the next time your being hunted by an ASW force :lol:

http://www.german-navy.de/kriegsmarine/ships/uboats/typxxi/index.html

[Hartmann]

I like a lot the what if.... for example if the kriegsmarine could develop the XXI technology early in the war and not delay improvements thinking that the war was near to finish in 1941.

[XXi]

Personally I like to use the XXI in GWX now, after MANY careers with IX ( B, C, D2 ) and VII ( virtually all types ) - it`s a very nice change when you see a boat that is SO much better.
Now Im playing XXI in 1940, just for fun :) and I must tell you that, however it`s not much demanding, it can still be quite fun.

Besides, playing the XXI with GWX is a good opportunity to see what the team can do, just compare it with the stock, buggy XXI :hmm: