Stealth technology

sav112 · 12-06-09, 07:32 AM

Watched a program on one of the documentary channels and they were investigating the disappearance and finding and diving on U480. It seems it was invisible to sonar and only sunk because the brits had laid a trap of mines in the channel.

I know it’s later in the War being end of 1944-45 but I did not realise these U-boats had this Rubber coating with various small holes that trapped the frequencies. Stealth technology

I take it this would be totally out of the game if you made it to 1945, I remember playing SH III on some Dx sub I'm sure it was and it was more or less like this and very fast.

Having missed SH IV I’m looking forward to this new game.

karamazovnew · 12-06-09, 08:13 AM

http://www.uboataces.com/sonar-coating.shtml

Quote:

(viii) Counter-measures against British Asdics
The Petty Officer Telegraphist stated that tests had been carried out on a U-Boat with a rubber coating over the whole boat, the rubber being stated to have been 1/2 inch thick. These tests had not proved successful, as the rubber covering had considerably decreased the speed of the boat.

taken from http://www.uboatarchive.net/U-574INT.htm

Also: http://www.history.navy.mil/branches/org12-5.htm

Since some types of Hydrophones, radars and why not, the Walter boats were all experimental and played little part in the overall battle, you might expect the devs to omit them. But they add a nice touch to the game and let's face it, we've all started a 39 campaign with the Type XXI at least once just to see "how it could've been".

mookiemookie · 12-06-09, 09:12 AM

The Alberich and Tarnmatte rubber coatings were indeed an upgrade in SH3. As I recall, each would reduce your sonar signature by 10%.

sav112 · 12-06-09, 10:30 AM

Unfortunately the crew were all but lost on this U-480 except for one that missed the outing due to him having bad feelings about a Woman that had been shown round the sub while back in base, The commander had given him the option to stay behind for training and saved his life.

It was his insight I found really interesting as he had said they had sunk four targets in the English channel and all hell had broke lose and they counted eighty-nine depth charges and only one was close and that was just luck. The coating was working 100% they could not be found.

Hope you get options to upgrade and have to fight to save your boat, I hated that Death screen you got in SHIII although I appreciate some times it would have been quick.

karamazovnew · 12-06-09, 11:02 AM

Having 100% sonar dispersion would be cheating. But I agree that 20% wasn't much in SH3

. Anyway, it's not like you become invisible to sonar. At close range they can still pick you up but very imprecise. And since they don't know where you are, they might mistake those small pongs for a very far away sub. Pings sent by one escort can even be received by another escort so imagine their confusion. And as soon as you reduce your profile by turning away from the hunters and put a bit of space, then you become invisible.

sav112 · 12-06-09, 11:09 AM

To me that was always the Joy of SH games, the attack then the ever so slowly creep away from the pursuers. I really can emit I never really enjoyed the Torpedo hits so much as the fight to escape that Destroyer that has it in for you.

Although I never had confidence in the Ai, always felt that the destroyer was cheating a bit.

12-06-09, 07:14 PM

Agreed. It's trying to escape or evade an ASW ship that knows his stuff, that makes SHIII exciting. I only see torpedo hits during surface attacks. For submerged attacks, I'll listen if curcumstances allow.

Platapus · 12-06-09, 08:33 PM

Alberich - which used a synethic rubber compound called Oppanol, Oppanol pannels were glued to the sides of the submarine as a way of both hindering active sonar by absorbing the active sonar pulses and reducing the sound signature of the submarine against passive hydrophones.

It was first used operationally (1940) on the U-67 Type IXC. The problem with Alberich was in the adhesive used. Gluing synethic rubber to steel alloys under water that can withstand the current effects as well as the temperature effects is difficult. Many experments showed that the tiles would strip away.

By 1944, improvements in adhesives were implemented on the U-480 Type VII successfully. Testing during the war and after showed that the Alberich tiles only reduced the active sonar signal (by absorbtion and redirection) by about 15%. Nice, but ultimately probably not worth the effort and expense.

http://www.uboataces.com/sonar-coating.shtml

12-06-09, 07:32 AM	#1
sav112 Gunner Join Date: Oct 2009 Location: Scotland Posts: 92 Downloads: 0 Uploads: 0	Stealth technology Watched a program on one of the documentary channels and they were investigating the disappearance and finding and diving on U480. It seems it was invisible to sonar and only sunk because the brits had laid a trap of mines in the channel. I know it’s later in the War being end of 1944-45 but I did not realise these U-boats had this Rubber coating with various small holes that trapped the frequencies. Stealth technology I take it this would be totally out of the game if you made it to 1945, I remember playing SH III on some Dx sub I'm sure it was and it was more or less like this and very fast. Having missed SH IV I’m looking forward to this new game. __________________

12-06-09, 09:12 AM	#3
mookiemookie Navy Seal Join Date: Nov 2005 Location: Houston, TX Posts: 9,404 Downloads: 105 Uploads: 1	The Alberich and Tarnmatte rubber coatings were indeed an upgrade in SH3. As I recall, each would reduce your sonar signature by 10%. __________________ They don’t think it be like it is, but it do. Want more U-boat Kaleun portraits for your SH3 Commander Profiles? Download the SH3 Commander Portrait Pack here.

12-06-09, 10:30 AM	#4
sav112 Gunner Join Date: Oct 2009 Location: Scotland Posts: 92 Downloads: 0 Uploads: 0	Unfortunately the crew were all but lost on this U-480 except for one that missed the outing due to him having bad feelings about a Woman that had been shown round the sub while back in base, The commander had given him the option to stay behind for training and saved his life. It was his insight I found really interesting as he had said they had sunk four targets in the English channel and all hell had broke lose and they counted eighty-nine depth charges and only one was close and that was just luck. The coating was working 100% they could not be found. Hope you get options to upgrade and have to fight to save your boat, I hated that Death screen you got in SHIII although I appreciate some times it would have been quick. __________________

12-06-09, 11:09 AM	#6
sav112 Gunner Join Date: Oct 2009 Location: Scotland Posts: 92 Downloads: 0 Uploads: 0	To me that was always the Joy of SH games, the attack then the ever so slowly creep away from the pursuers. I really can emit I never really enjoyed the Torpedo hits so much as the fight to escape that Destroyer that has it in for you. Although I never had confidence in the Ai, always felt that the destroyer was cheating a bit. __________________

12-06-09, 08:33 PM	#8
Platapus Fleet Admiral Join Date: Oct 2006 Posts: 19,379 Downloads: 63 Uploads: 0	Alberich - which used a synethic rubber compound called Oppanol, Oppanol pannels were glued to the sides of the submarine as a way of both hindering active sonar by absorbing the active sonar pulses and reducing the sound signature of the submarine against passive hydrophones. It was first used operationally (1940) on the U-67 Type IXC. The problem with Alberich was in the adhesive used. Gluing synethic rubber to steel alloys under water that can withstand the current effects as well as the temperature effects is difficult. Many experments showed that the tiles would strip away. By 1944, improvements in adhesives were implemented on the U-480 Type VII successfully. Testing during the war and after showed that the Alberich tiles only reduced the active sonar signal (by absorbtion and redirection) by about 15%. Nice, but ultimately probably not worth the effort and expense. http://www.uboataces.com/sonar-coating.shtml __________________ abusus non tollit usum - A right should NOT be withheld from people on the basis that some tend to abuse that right.

12-06-09, 11:02 AM	#5
karamazovnew The Old Man Join Date: Mar 2009 Location: Bucharest, Romania Posts: 1,403 Downloads: 151 Uploads: 0	Having 100% sonar dispersion would be cheating. But I agree that 20% wasn't much in SH3 . Anyway, it's not like you become invisible to sonar. At close range they can still pick you up but very imprecise. And since they don't know where you are, they might mistake those small pongs for a very far away sub. Pings sent by one escort can even be received by another escort so imagine their confusion. And as soon as you reduce your profile by turning away from the hunters and put a bit of space, then you become invisible.

12-06-09, 07:14 PM	#7
Snestorm Stowaway Posts: n/a Downloads: Uploads:	Agreed. It's trying to escape or evade an ASW ship that knows his stuff, that makes SHIII exciting. I only see torpedo hits during surface attacks. For submerged attacks, I'll listen if curcumstances allow.