The American Mystery Sub

Originally posted by skippytjc
Why not? They have already SUCCESSFULLY fired torpedos under water mach 1, why cant a sub go 65mph? Ill need to pull the article, but it was a Pupular Science issue this past year. I read someplace the Russians are chasing it too. Only huccup so far is they cant steer it yet.

Well firstly the torpedo was shooting water infront of it.
Second the torpedo is smaller and lighter than a sub.
Third a sub cant really risk itself like a torpedo can.

I understand all of that. But to say its impossible for a sub to go 65 is innacurate. They can easily make that so, it just isnt a good idea. And how do we know for certain, I mean really know they cant go 65? We just dont know. But from a mechanical stand point, its possible.

Originally posted by skippytjc
I understand all of that. But to say its impossible for a sub to go 65 is innacurate. They can easily make that so, it just isnt a good idea. And how do we know for certain, I mean really know they cant go 65? We just dont know. But from a mechanical stand point, its possible.

Well stress on the front of the ship,tower,planes and the such might be a cause.

Originally posted by COWlan
Usually the faster submarines move, the more noise they produce and therefore will make sonars and weapons lock onto them more easily. The more noise the submarine makes it self will also degrade the accuracy of their own on board sonar because there are just too much noise to accurately detect other subs.

seawolfs are compleatly silent at under 25 knots so at 55 knots they will make the same amount of noise as a normal submarine does at 15-20 knots.

Janes fighting ships/aircraft makes for good and intresting reading. Just remember that much of the new gear and equipment coming out is classified. Do you think that Janes is going to put out accurate performance figures in certain arenas?? How much is politics and misinformation is anyone guess. I'm just saying ..dont look to Janes for the absolute truth in performance data. Very intresting reading yes....absolute truth ..no.
Another thing for some of you to realize...the Navys of the world are not much different from hot rodders..looking for the next racing edge..out on the track. Their prime limitation is budget....just like the rest of us. The Navys of the world..budgets allowing ..are not beyond trying some new gimick or gadget to get more performance...out of a ship or boat. Not just speed...but quiteness too. THey dont usually post this kind of thinking per se in Janes. THere are civilian teams who go around to certian Navy ships to tweak and adjust certain performances out of them. Modifications too.
My point is that not all is in the books..for the public to see and for good reasons.
Some of you need to think this through about top speeds....carefully. Also someone got it correctly...when they said how quiet is a boat at that speed. The trick is to raise the speed without losing the quiet threshold. To be able to raise the speed and still remain quiet. A huge task in degrees of difficultys encountered!!

Great posts here
Thanks to all,
Orangetom

Speed is not necessarily everything in this type of buisness...Dont get enamoured of it.

Thanks,
Orangetom

Well it would make sense, the USS Jimmy Carter is 100 feet longer then the other Sea Wolf’s, more room for a more power reactor, or perhaps two reactors? I know they claim its for SEAL operations but it could just be a cover. Orangetom do you have anything to add about the Sea Wolf’s real top speed? You’re pretty knowledgeable to say the least about subs and their capabilities.

Good to see your post again.

First off ..let me say that the US Navy has tried two reactor submarines and found it complex and impractical. Expensive too. The USS Triton is the boat that comes to mind..long since decommissioned. They have long since gone to a one reactor design with more than enought available power to get the job done. I can assure you that they have all the steam head pressure and volume to get the job done and then some.

As to speeds on the Seawolf or other boats of a series..this information is classified. Suffice it to say that speeds are not a problem. Dont count on Janes for this information either.
It is classified sufficiently that when you see a boat out of the water or in a drydock the wheels..or propellors are covered up by tarps. Look at the picture of the Virginia Class boat on the outside plattens in the board titled "The new Iranian Submarine." Page 3 under Pavil's post. You see four pictures at he bottom of the page of the USS Virginia...three from the front..no view of the propellor/propulsor. The fourth picture is of a tarpulin covering it up and the frame cuts out part of the picture at the right side. If you are ever lucky enough to see one not covered ..someone goofed up big time. This was true of the all the Los Angeles 688 class boats ..same with the 637 class boats and boomers before them.
Sorry olde man but thats all I will say on the subject..and this will have to suffice.

Thanks for your post..good to see you again,
Orangetom

Great picture of Teddy Roosevelt in your post..thanks,
Orangetom

When did this accident in the Indian Ocean happen? Where exactly?
Was this very recent?

It is classified sufficiently that when you see a boat out of the water or in a drydock the wheels..or propellors are covered up by tarps.

Yeah you’re right about that, I searched to see if I could find any propeller pictures of the Virginia class but I was unable to. In all the pictures they are all covered up. Also, thanks for your information concerning double reactor subs, I was unaware of the USS Triton.















[edit on 5-2-2006 by WestPoint23]

Wow...great pictures there. Not all of which I have seen before.

The first one is a section of submarine not completed but being moved into a building before being joined to the rest of the hull sections. It is the aft engine room section. You are not actually seeing the propellor section as it has not been installed as of yet. What the tarp is covering is a large hole where the propellor shaft goes through. The shaft does not appear to be installed as of that picture. It is very likely that it is mostly at this stage a hollow inner hull and ballast tanks. You see clearly the rudder and stern planes. It is a great picture ..I just didnt expect to see that one on the web. Wow!! This picture is at Newport News.

The second and fourth pictures are of the USS Texas by the flag on the sail structure ..the Lone Star on the flag clearly marking her a the USS Texas. I have worked on this boat. You see the floating drydock behind her where she eventually was lowered into the water. I was also priveleged to be there the night she was lowered into the James River. There are pictures circulating around the web of this event.
It had been years since this yard had lowered a whole submarine into the water ..it was sort of a milestone of getting back into the submarine buisness. The last one had been the USS Cheyene some ten years or more before the USS Texas.
Good to see you understand my point about the propellors and propulsion systems and the security status of these.

The other pictures are all up at Electric boat. Still great pictures.
Thanks for the pics West Point.

OH..and the pictures of the boats in the buildings..this is a huge improvement on how they used to build them on inclined shipways. mostly outdoors covered by tents or canvas in places...those were rough days. I mean to tell you ..West Point...cold and damp..or very hot in the summers. These buildings afford much more controlled conditions and better welding enviornment. In the olde days the welders used to get sent home if the weather was to rough..you couldnt control the enviornment that well ..under tents and tarps. Water would get through and pose a electrocution hazard. Much Much better conditions in these buildings today.
Also if you look closely at the picture of the boat in the building..you see the sonar dome..covered with a tarp. If you look at the top of the hull aft of the sonar array you see some black rectangular doors...eight of them. Four on the top centerline....and two..longer ones ..below them. Same configuration on the other side of the centerline..twelve total. These are the vertical launch tomahawk missle tubes spoken about on the thread.."New Iranian submarine." These have been photographed in Tom Clancys books before covering 688 class boats so it is not a new thing.


Once again ..thanks for some great pics.
Orangetom

The Seawolf didn't have a tarp covering its propulsor, how come? Of course you don't need to cover it when you can just take pictures of the submarine in different angles that don't show the pump jet.

Bumping this thread back up for the benifit of BASSPLYR and others on the thread US Navy Punked by third world nations.

Orangetom

Originally posted by blue cell


That is dependant on thier shape. From my understanding a huge amount of the noise comes from the pumps for the reactors and the like.

Also anechoic tiles can reduce the sound emitted out side the sub from the machinery that makes the ship move. Also dosen't the Sea Wolf use a pumpjet propulsor? Which is much quieter than conventional propulsion systems.

Yes the seawolf uses a pumpjet propulsor which is quieter,and The Brits abandoned propellors for pumpjets with the Tragalfar class.However pumpjets are heavy so don't expect an SSK to run on one !

However some of you guys are really operating under some serious misconceptions about modern naval reators!
They don't use pumps anymore to cool they use silent convection which is ALOT quieter
Seawolf and Virginia both have this.

Tragalfar use of it.

Rather than the seven/nine-bladed propeller used by the Swiftsures, Trafalgar class submarines use pump-jet propulsion - a high-pitch, low-revolution propeller which is much quieter but much heavier than conventional propeller designs.

en.wikipedia.org...

Seawolf reactor en.wikipedia.org...

Virginia reactor en.wikipedia.org...

here's an interesting detailed article on new Reactors and how they work.

www.phyast.pitt.edu...


I think covering up the propeller reduces wake(It's my guess).

[edit on 26-10-2006 by urmomma158]

[edit on 26-10-2006 by urmomma158]

I don't even know where the original poster is getting 65 MPH. I scanned through the 2 links provided and the one only mentions the standard "25+ knots" speed which doesn't translate to 65 MPH. 65 KILOMETERS per hour is reasonable. 65KPH = 40 MPH

Originally posted by urmomma158
However some of you guys are really operating under some serious misconceptions about modern naval reators!
They don't use pumps anymore to cool they use silent convection which is ALOT quieter
Seawolf and Virginia both have this.

They may use natural recirculation for slower speeds, but I would be very surprised if there weren't still conventional RCP for high speed transits. I don't think you can say one way or the other what type of RCP configuration Seawolf and Virginia use as this would be classified and restricted information. The pitt.edu link is talking about commerical power plants.

Top speed is really only important for cross ocean transits.
If the Navy is at all worried about remaining silent and undetected the ship will not
be cruising around at flank speed.

Also I can guarantee that 65 km/hour figure for USS Jimmy Carter is low.
For years, Los Angeles boats' unclassified top speed was "in excess of 20mph"
and then it was changed to "in excess of 25mph". Of course they don't reveal the real top speed. 65 km/hour is about 30mph. That's probably just what they are willing to admit. Also, since it's got the hull stretch, USS Jimmy Carter is probably slower than USS Seawolf or USS Connecticut.

As for a true 65mph top speed, it's probably technically feasible although not practical. The hull would have to be thinner thus limiting diving depth. Also control surface malfunctions are a concern with high speed submerged operation.
Going 65mph and having the stern planes jam would mean instant death.
Think about going from 500 feet to 2500 feet in less than 10 seconds. LOL

Originally posted by Schaden

As for a true 65mph top speed, it's probably technically feasible although not practical. The hull would have to be thinner thus limiting diving depth. Also control surface malfunctions are a concern with high speed submerged operation.
Going 65mph and having the stern planes jam would mean instant death.
Think about going from 500 feet to 2500 feet in less than 10 seconds. LOL

THis is no joke...it would happen about that fast if not faster. A disaster...in the making if the equipment is not working perfectly.

Thanks,
Orangetom

To sort of revive an old topic, I was cursing around and found this picture of a German Type U212 sub propeller. Now Orangetom, is this a slipup on their part or is our policy unique in that it allows no public pictures of active sub propellers?

Originally posted by WestPoint23
To sort of revive an old topic, I was cursing around and found this picture of a German Type U212 sub propeller. Now Orangetom, is this a slipup on their part or is our policy unique in that it allows no public pictures of active sub propellers?

Good to hear from you again. YOu have a penchant for finding these pictures. It is normal for them. It is our policy to not show the wheels/propellors. I have seen a photo of a French boat and its propulsor. This would not be seen on a US Navy boat.

I'd sure like to see the engine room on this boat.

Remember also that this boat is designed to run quiet not necessarily fast. While this wheel will run at considerable speed if it had the torque and rpm...the boat will not be quiet per se...just like most boats..at speed.
As I recall this type of boat will actually run faster on the surface or on diesels..or submerged with the snorkel out ...than completely underwater. Running hard when submerged will use up power quickly. This is the significant difference in nuclear boats and non nuclear. Unlimited go..at any speed.

Also notice that this boat has the aft planes in a X configuration verses the vertical/horizontal rudder/dive planes configuration that we use. This is supposed to be a very maneuverable configuration. I dont know why we did not use it other than on a small number of boats before going back to the vertical/horizontal configuration of today.

Great Picture you found here.

Thanks,
Orangetom