tek@CS.UCLA.EDU (Ted Kim (ATW)) (07/08/89)
From: tek@CS.UCLA.EDU (Ted Kim (ATW)) >From: gahooten@ames.arc.nasa.gov (Greg A. Hooten) > ... >US News said that the cost of a 688 attack sub is about 533 >million dollars, but the next generation (Seawolf?) will cost >about 2 Billion. It will speed along at 35 Knots (vs. 31 >Knots) and dive a little deeper (1000 ft), but with that cost, >it would be nice to have it do a lot more. Does anyone know >what this new generation sub will do that the 688 will not? >Maybe it is quiter, but how much? I don't know if it will be worth it, but here are some of the things that the Seawolf class (SSN-21) will supposedly have over Los Angeles class (SSN-688) and Improved Los Angeles class (SSN-751): 1. 8 x 30" torpedo tubes (vs. 4 x 21") The 30" size allows quieter torpedo "swimout" instead of compressed gas ejection launch. It gives them the option to go for a bigger torpedo later (like those big Soviet Type 65s). It also allows launching of the Sea Lance. All the old stuff can also be launched: encapsulated Harpoon and Tomahawk. (Note only some LA Class can fire Tomahawk from torpedo tubes.) Eight tubes also potentially gives you a chance to cut loose a bigger salvo when you do fire or have more types of weapons ready at once. Note that no VL Tomahawk are installed as on Improved LA. But on the other hand, you don't care so much about competition for tube space as when you only have four tubes. Also the VL launchers are not reloadable at sea. 2. under ice mods As on the Improved LA, control planes moved to the bow and made retractable. 3. quieter Anechoic coating and pump jet propulsor. (Some Improved LA have similar changes equipment.) First unit of Seawolf may have large, shrounded, 7-bladed, slow-turning variable pitch propellor instead. How much quieter is, of course, what we all want to know and is probably classified. 4. larger weapon space Seawolf carries about 50 weapons (about double LA class). 5. better sonar/electronics Carries a new integrated fire control/sonar suite, which has been argued over endlessly. The sonar (bow-mounted?, hull-mounted conformal array and towed-array) will, of course, be more sensitive than before. There is also a new highly directional sonar added whose purpose is to help get faster passive fire control solutions. Ted Kim ARPAnet: tek@penzance.cs.ucla.edu UCLA Computer Science Department UUCP: ...!ucbvax!cs.ucla.edu!tek 3804C Boelter Hall PHONE: (213) 206-8696 Los Angeles, CA 90024 ESPnet: tek@ouija.board
daveme%tekirl.labs.tek.com@RELAY.CS.NET (Dave Mead) (07/12/89)
From: Dave Mead <daveme%tekirl.labs.tek.com@RELAY.CS.NET> I thought the new attack subs would have a *much* faster hull speed for quiet running (laminar flow?). All fast current subs make a lot of noise when running near max speed and can only achieve ~6 knots or so quiet. New tricks and coatings allow the new subs to go *fast* and *quiet* at the same time. A big improvement.
tek@CS.UCLA.EDU (Ted Kim (ATW)) (07/13/89)
From: tek@CS.UCLA.EDU (Ted Kim (ATW)) In article <8181@cbnews.ATT.COM> Dave Mead writes: > >I thought the new attack subs would have a *much* faster hull speed for >quiet running (laminar flow?). All fast current subs make a lot of noise >when running near max speed and can only achieve ~6 knots or so quiet. New >tricks and coatings allow the new subs to go *fast* and *quiet* at the >same time. A big improvement. The information I have heard, has Seawolf capable of going "silent" upto ~15 knots (vs. ~5 knots for LA Class). The pump jet propulsion unit is not supposed to cavitate at any speed the sub is capable of. (Though, cavitation along certain hull points may occur at high speeds.) I have heard LA Class screws start cavitating somewhere in the 15-25 knot range. Also, in my previous article, I gave the impression that Improved LA would not be able to fire the new Sea Lance (when available). This is incorrect. -ted Ted Kim ARPAnet: tek@penzance.cs.ucla.edu UCLA Computer Science Department UUCP: ...!ucbvax!cs.ucla.edu!tek 3804C Boelter Hall PHONE: (213) 206-8696 Los Angeles, CA 90024 ESPnet: tek@ouija.board