Alberich Coating ~ Effective?

[Krauter]

Does this actually work against enemy sonar? Or does it just apply as a skin and that's the end of it

[walsh2509]

from another forum .. and I seen the same program

Just saw a new National Geographic Explorer that found the U480 and solved the mystery. How could the German sub operate with impunity in the English Channel?

The secret? Stealth technology! A multi-rubber coating with air pockets applied to the hull prevented the "Ping" from destroyers from finding the sub. There were six built and none were descovered.

U480 was sunk by guile. The sub returmed to its prior successful hunting territory. The English diverted the convoys to another route, however, they left the lane markers intact and planted a mine field. U480 acted exactly as expected and the rest is history.

The multilayered rubber coating required laborous preparation and application. It sounds very much like the coatings applied to modern stealth aircraft, although the materials have certainly evolved. Apparently, the German secret never was determined although through "The Bomb," some code breaking device, it was determined that something was making the sub "invisible."

It's always a cat and mouse game and I wonder what the above water sailors knew and when they knew it?

[Krauter]

It is in fact a rubber coating that absorbs the sound waves, much similar to todays modern submarines anechoic coating.

What I'm asking is.. IN-GAME does it affect enemy sensors? or is it just for show?

[Defiance]

Saw a docu not long back with it in

They found the covering had two different sized holes/indents

They reckoned it was (easiest term for me from memory) to absorb two differing frequencies bounced at the hull (or somert to that effect)

An account either by records or interview (memories so bad it fails me lol) said the sub seemed totally cloaked and nothing detected them (maybe someone more historically minded would know which sub/captain ? )

Not that i would like it in-game as such, rather takes the fun and intensity away i'd feel

Hey walsh, you in the UK (guess your not, just seen ya sig) i think we musta seen the same docu, i think i saw it 2 mth or so ago, can't rem which channel though

[oscar19681]

So does it work in-game yes or no?

[Defiance]

From what i gather nope, it makes no difference in the game

[Taurolas]

Originally Posted by Defiance

From what i gather nope, it makes no difference in the game

I was looking through some files the other day and came across the coatings..
looks like the Alberich Coating is supposed to give you around a 30% reduction in being detected.
I'm not saying it works as i have yet to try it, could really do with a mission with and without the coating to verify this issue.

[Zedi]

I used it through the whole Western Approaches campaign and it's useless, no matter if you use AI improvement mod or not. The only use was to show off with my black sub in (enemy) ports to impress the chicks

[msxyz]

The Germans experimented with several coating materials to reduce both sonar and radar signature.

The solutions found are basically the same employed today. Both are based on hard synthetic rubber. The Albericht was a 4-5mmthink rubber texture with hollow channels running on the inside.

It was found that sonar echoes were reduced, on average, by 15-20% while the coating also damped the internal noises made by the submarine machinery (pumps, ventilation systems and, while on the surface, diesels).

Unfortunately the thin rubber skin peeled off quickly while cruising at high speed. Partially detached panels would start vibrating in the water worsening the sound signature of the boat. It was deemed impratical and the advantage gained against active sonar was small.

After the war, USSR continued the research on anti sonar coatings using German data. By the early 60's they perfected a thicker rubber (50mm) tile which was much more effective at damping sonar noise. The Russian submarine Project 651, a huge diesel elecrtic boat deisgned to carry four nuclear tipped cruise missiles, was covered with such tiles. Together with an underwater range of 800Nm (thanks to silver zinc batteries) using its "silent" motor it could approach undetected enemy ports or carrier groups. This wasn't possible with the nuclear submarines of the day which were much noisier.

The Germans also studied a radar absorbing material which was essentially composed of several layers of thin rubber sheets with graphite dispersed into it in several different concentrations to maximize reflection lossess.

The principle is essentially the same employed today by stealth planes. It works very well with centimetric waves but it's useless against low frequency (in the VHF domain) radars.

This isn't a problem if you're covering a snorkel mast (VHF radars cannot detect such small objects) but it is ineffective if used on a bigger surfaces like a conning tower. Not to mention that these coatings reduce the signature but they don't prevent some energy to be reflected back to the radar. The odd shape stealth planes must employ (sometimes at the cost of aereodynamic efficiency) is designed to scatter the reflected energy everywhere so that the radar antenna cannot pick up a useful quantity of it.

As for SH5... I don't know

[The General]

Wow, I never knew this German engineering is incredible! Whomever came up with the Alberich Coating is a bonafide genius(somebody called Alberich perhaps?).

Originally Posted by Magnum

I used it through the whole Western Approaches campaign and it's useless, no matter if you use AI improvement mod or not. The only use was to show off with my black sub in (enemy) ports to impress the chicks

It shouldn't be to difficult to Mod a reduction in Sonar signature. I recommend you ask Nisgesis

[ReFaN]

as destroyers wont attack you either way, i cant say

[Akula]

Interesting Topic indeed!

I hope that the again a mod or patch will at least make it more than just eye candy.

Back to facts:

The Alberich synthetic rubber systems main vice was the adhesive used which was unreliable at best. As mentioned here before, the sheets tended to get loose and flap around creating more noise and resistance.

The adhesive was improved, but again the war came to an end before any futher breakthroughs could be made in this area, and even the British apparently after the war gave up when looking at German examples as the adhesive was still an issue afterwards for a while anyway.

Tarnmatte was the radar absorbant material use to cover protruding parts of the U-boat such as the Schnorkel cover heads, not sure about Periscopes but claimed to be 90% effective to reduce the radar signature.

Of course something seldom mentioned about Alberich, as it covered large areas of the boat was the added weight that it introduced.

Still very interesting and amazing technology for the time.

[danasan]

Originally Posted by The General

Wow, I never knew this German engineering is incredible! Whomever came up with the Alberich Coating is a bonafide genius(somebody called Alberich perhaps?).It shouldn't be to difficult to Mod a reduction in Sonar signature. I recommend you ask Nisgesis

The name should be taken from the Nibelungen saga / Richard Wagner (composer). You'll find a lot of examples where Nibelungen saga / Wagner was used. Hitler was keen on that stuff.

Alberich = name of a king in German mythology who had had a stealth coat!

Nibelung itself, Sieglinde, Siegmund and so on...

danasan

[msxyz]

I think Alberich is the name of some demigod/hero in the northern folklore.

Maybe Google will give you some answers.

EDIT: someone answered that for me! 0wn3d

[Zedi]

Quoting from the mighty Wikipedia:

Anechoic tile:

Anechoic tiles are rubber or Sorbothane-like tiles containing thousands of tiny voids, applied to the outer hulls of military ships and submarines, as well as anechoic chambers. Their function is twofold:

- To absorb the sonar sound waves of active sonar, reducing and distorting the return signal thereby reducing its effective range
- To attenuate the sounds emitted from the vessel, typically its engines, to reduce the range at which it can be detected by passive sonar

History:

The technology of anechoic tiles was developed by Germany in the Second World War. Code named Alberich after an invisible sorcerer from Germanic Mythology, it was a 4 mm thick coating of rubber for submarines that attenuated sound in the 10 kHz to 18 kHz range to 15% of its normal strength. This frequency range matched the operating range of the early ASDIC active sonar used by the allies. ASDICs operating range would have been correspondingly reduced from its optimal range of 2000 meters to somewhere around 300 meters. The rubber contained a series of small voids, which helped to break up sound waves.

The problem was that the material performed differently at different depths, due to the voids being compressed by water pressure. Another problem was attaching the tiles to the submarine, which required a special adhesive and careful application. The first tests were conducted in 1940, but it was not operational until 1944, when it was successfully utilized by U480.

After the war it was not used until the 1970s when the Soviet Union began coating its submarines in rubber tiles. These were initially prone to falling off, but as the technology matured it was apparent that the tiles were having a dramatic effect in reducing the submarines' acoustic signatures. Modern Russian tiles are about 100 mm thick, and apparently reduced the acoustic signature of Akula class submarines by between 10 and 20 decibels (10% to 1% of its original strength).

The modern materials consist of a number of layers and many different sized voids, each targeted at a specific sound frequency range at different depths. Different materials are sometimes used in different areas of the submarine to better absorb specific frequencies associated with machinery at that location inside the hull.

The US Navy began applying a similar coating to its submarines in 1988, and other navies quickly followed suit.