U.S. Nuclear Subs Vulnerable to attack

After leaving it wide open for everyone on Google Earth to see, the prop of a U.S. nuclear submarine in dry dock was revealed. They almost always cover the prop, being one of the most secretive and important parts of a sub; it’s one of the keys to underwater stealth: The design of the blade is supposed to cut through the water as quietly as possible. You can even see the prop covered on the above picture of the new German 212 Diesel Sub. I would think with the clear photo I saw from Google Earth any country could make a perfect copy of the prop. Is the Navy really that loose, or was it the ship yard workers? If we really are getting lax about stuff that is supposed to be super secret maybe it’s obsolete. Could the Navy have a whole new propulsion system we don’t know about? Think of the Caterpillar system from the move The Hunt for Red October. Or maybe we copied some natural sea life and have a propulsion system more like a squid, octopus, or nautilus? No external moving parts I would imagine less noise.

A magnetohydrodynamic drive or MHD propulsor, is a method for propelling seagoing vessels using only electric and magnetic fields with no moving parts, using magnetohydrodynamics.

Magnetohydrodynamic drive

This is an experimental Japanese ship that was propelled by the magnetohydrodynamic drive. I bet I could cause quite a stir if I posted this pic on the Aliens and UFO Forum as a UFO. From what I read the drive is noisy and doesn’t propel the vessel very fast, yet it’s very fascinating how it works. Or maybe it has been perfected?






[edit on 16-11-2007 by jojoKnowsBest]

Jojo and others on this thread.

I am going to point out a couple of things about the photos of the U212 on page 1 of this thread.

Look at the photos of the rear of the boat. Notice that the control surfaces are in a X pattern verses the standard + pattern used on our submarines.

We have expereimented with the X pattern for our boats but for some reason discarded it and now use the + pattern of rudder and stern planes.
It is said that the X pattern makes a boat more maneuverable than the system we in the USA use.

Also notice that there is a cable system going around the X pattern to form a square on the rear control surfaces. This system would prevent a boat from traveling fast speeds underwater unless a sufficient depth could be found where water pressure could help overcome the flow noise resonating over the cable. At certain speeds it would sing.
Same thing I noticed on a Iranian submarine photo posted here in the Weapons forum. This boat had permanently welded handrails on the sail structure for when men were posted to stand watchs. This handrail system would sing under any kind of fast speed.. resonate ..if these boats could in fact travel that fast underwater.

The other thing I observe on this U212 boat is that with the X system on the stern...is there a faciliy for a towed array sonar out back? A pipe ..as noticed on the photos of the Astute class boats. A pipe clearing the propellor. Check it out on the photos posted here on ATS Weapons boards..you see a long pipe sticking out center line rear of the Astutes. ...rearward to clear the propulsor system.

How do you do this on a X system boat?? I dont see a pipe making me think that there is no towed array sonar.

Towed Array Sonar is an attempt to use a rearward towed cable with sensors to overcome a certain blind spot due to the location of the propellor or propulsor. Are these boats blind from the rear??

Just some observations.

Thanks,
Orangetom

reply to post by orangetom1999



Thanks OT for your input, it seems you know a great deal about subs, were you in the Navy, worked in the shipyards? I never did, but since I was a little kid I always had a fascination with ships and subs. I just checked out the new Nuclear Attack sub for the UK, that thing looks ominous. I read that is uses torpedoes with directed energy warheads; I couldn’t find much info on them, does anyone know how a DE torpedo works?

The Spearfish torpedo from BAE Systems is wire-guided with an active / passive homing head. The range is 65km at 60kt. Spearfish is fitted with a directed-energy warhead.

naval-technology.com

OT works within the industry and is very knowledgeable with regards to subs


and as for your `hydromagnetodrive` pumpjets or propulsors allready are in use.

reply to post by Harlequin



Its funny you mention that, after asking about the possible use of pumpjets I did some research and found that many subs are starting to use them, even the U.S Navy Seawolf Class attack sub. At that point it was starting look like I was talking to myself so I refrained on posting any info about it. If anyone cares to look, this is a great example of a real life pump jet system used on a modern sub, possibly one of the most advanced.

SSN-21 Seawolf-class specs

General Dynamics Electric Boat Division
Power Plant One S6W reactor
one shaft at with 52,000 shp with pumpjet propulsor

Improved Performance Machinery Program Phase II one secondary propulsion submerged motor
Length 353 feet (107.6 meters)
Draft 35 feet (10.67 meters)
Beam 40 feet (12.2 meters)
Displacement 7,460 ton surface displacement
9,137 tons submerged displacement
Speed Official: 25+ knots (28+ miles per hour, 46.3+ kph)
Actual: 35 knots maximum submerged speed
Actual: 20 knots tactical ["silent"] speed
Operating Depth Official: "greater than 800 feet"
Actual: About 1600 feet
Jane's Fighting Ships: 2000 feet
Armament eight 660-mm torpedo tubes
50 Tomahawk cruise missiles or
50 Harpoon antiship missiles or
50 Mark 48 ADCAP torpedoes or
up to 100 mines
Crew 12 Officers; 121 Enlisted

From what I read it seems to be the leader of the pack for Hunter/Killer subs, plus its abilities are not limited to attacking, it can provide many support roles including land and fleet.

SSN-21 Seawolf-class

Jo Jo and others,

I have been considering this post for a few day now..and decided to repost and clarify a couple of things.

First off Harlequin is correct. I am in the industy and I offer this site for information purposes


www.nn.northropgrumman.com...

I have been at that site above for a number of years and been privileged to work on a number of boats built here including the Virginias and 688 class. I am currently on Aircraft Carriers but I sure miss working on the submarines. To much darned walking on carriers for me. Never did take to working on these Nimitz Class ships.

It is simply by occupation that I know instinctively ..certain ear marks or design features to observe when I see a boat or photo of the same.

However to be fair to other countrys and the design/construction industry ..there are new designs and new equipments coming out...and coming out at a faster pace than in years past.
In some areas they are literally into flash gordon tech ..to use a poor catch word.

The list you posted on the characteristics of the Sea Wolf boats.

I will tell you a couple of things to note of this list and what is known in the trades.

First off the Sea Wolf for only three boats was an extremely expensive project. Not that the 688 project was cheap mind you ..it was not.
Sea Wolf is using a higher grade of steel in the hulls than previous boats. Translate that more expensive. For higher grades of such steel used mostly in combat ships and boats...the price of this steel is like exponential..as you go up in grades or strengths.
Also at the time ..sea wolf had some of the most up to date electronics. This was first used on the Sea Wolf boats.
Newer Submarines are similar the F16 aircraft..fly by wire. You go into the control rooms it is like..a joy stick instead of the yoke you see on so many boats. Look at the U212 photos and you see the type of steering yoke you expect on a bomber like a B52. Sailors who like video games and gaming would like this kind of set up.
This caught my eye immediately.
The new boats will be fly by wire. I was floored when I first saw this in a plane like the F 16 and understood what I was seeing.

Notice the torpedo room or torpedo tube dimensions on the list. 660mm diameter tubes. The standard in most nations is 533mm or 21 inches. 660mm works out to some 30 inch diameter if memory serves me correctly. This was done because the then Soviet designs coming out were heavy duty double hull designs. You needed a bigger bang to get through them. This is a big torpedo tube.

Nevertheless Sea Wolf is a very expensive and complex design. The base for the newer generations to come. I believe she was also designed in a day when more computer technology was brought on line to facillitate construction. A new milestone in this arena too. Virginias are heavily computer designed but Sea Wolfs broke the ground here so to speak.

Alot of what I am telling you here can be found on the web if you understand what you are reading. Much of this info is very dry and boring to most peoples.

Just some trivia for you to digest.
Gotta shove off
Fair winds.

Thanks,
Orangetom


[edit on 19-11-2007 by orangetom1999]

Originally posted by Harlequin

and as for your `hydromagnetodrive` pumpjets or propulsors allready are in use.

There is a massive difference between an electromagnetohydrodynamic drive (catapiller from HFRO) and the pumpjets currently in service. They work on entirely different principals.

The Yamato 1 (the MHD ship) only managed to achieve 15km/h as a top speed, this was massivly below what the engineers wanted. MHD sufferes from the problem that due to low conductivity of the the seawater, the magnetic fields required to drive it are beyond current tech, even with superconducting magnets

Originally posted by orangetom1999
....
Also notice that there is a cable system going around the X pattern to form a square on the rear control surfaces. This system would prevent a boat from traveling fast speeds underwater unless a sufficient depth could be found where water pressure could help overcome the flow noise resonating over the cable. At certain speeds it would sing. ...

I don´t know the reason for the cables, but they appear to be optional. Here are photos of serial No. 182 with the cables and No. 181 without them. The photos are from the same day and, actually the boats lie on opposite sides of the same quay.

Nevertheless, could it be some sort of "peacetime" configuration to mask the actual traveling sound, just like the American stealth planes have retractable antennas?

How do you do this on a X system boat?? I dont see a pipe making me think that there is no towed array sonar.

O-Tom, how could you of all people expect there were no towed sensors? ;-) The "pipe" you are looking for is going straight downward, at the point where the hull starts getting thinner towards the stern end. Since this is both underwater and also not exactly the chocolate side of the boat you won´t find many illustrations of it.

Since the U212A is a doubledecker in a small package, it is quite "fat" in the vertical direction. Coupled with the downward pipe the towed array will have several meters of clearance between its cable and the propeller, so there is little risk of damage.

Originally posted by orangetom1999

Newer Submarines are similar the F16 aircraft..fly by wire. You go into the control rooms it is like..a joy stick instead of the yoke you see on so many boats. Look at the U212 photos and you see the type of steering yoke you expect on a bomber like a B52. Sailors who like video games and gaming would like this kind of set up.

I never saw the new tech but heard it was coming. You know the early LA boats, SCP had das boot gages & mechanical yokes with aircraft style controls. Rig for dive in forward compartment upper level was a nightmare. So many valves crammed into a tight area. The new electro-optical masts must save time and money. Pulling the type 18 with a crane is a big hassle.

Lonestar,
Thanks for the explaination and the photos. I had not before seen those photos. I am also intrested in how the yoke configuration for X planes is set up in the after section of the boat or what I call the Mud Tank where it would be flooded.

I am not sure I am clearly understanding what you are telling me about this pipe configuration. Straight down?? This does not seem like a good configuration. It would need to be angeled back somewhat or straight back. It would seem that a straight down system would put undue strain on the cable at 90 degrees

Also I have not seen photos of the underside of the hull as I am not particularly researching the U212 class boats.

Also they dont seem to weight out much in the line up ..tonnage wise. I am asking myself ..how thick are the hull plates. Diving depth. Alot of this depth must be based on a small hull configuration. Smaller diameter hulls taking more depth/pressure than larger hulls of the same materials.

Thanks again for the photos...I had not seen them prior to your post.

Schaden,

I never saw the new tech but heard it was coming. You know the early LA boats, SCP had das boot gages & mechanical yokes with aircraft style controls. Rig for dive in forward compartment upper level was a nightmare. So many valves crammed into a tight area. The new electro-optical masts must save time and money. Pulling the type 18 with a crane is a big hassle.

Yes, I know about the gages and mechanical yokes having worked on the LA when it was being built. Some of the passageways and stair wells were different than later classes that came along. Absolutely yes..so many valves crammed into a very small tight area. Yes..that little area right behing the console with the steering yokes was a nightmare. I spent alot of time back there doing hydraulic flushes and grooming out those systems. Lockwiring too. "Patience Luke...Patience...use the Force.." You have to keep your cool in those tight spaces. There is absolutely no room back there to get pissed off or stupid. It just isnt there.

Good grief Shaden..you have pulled out and replaced Type 18s. So have I. It is a long grueling involved process. You have earned your moneys doing that job! Every penny!

Agree on the optical masts were a long time coming. Its a bit unusual at first not to see a scope mast penetrating the hulls in the old manner but it is the wave of the future. About time too!

Thanks,
Orangetom