sci.military.naval FAQ, Part G

Revised 30 March 2000
Version 1.51
Compiled and Maintained by: Andrew Toppan
SMN FAQ Main Page:

Contents of this section:
Section G.1: How are old nuclear submarines being disposed of?
Section G.2: Why are relatively modern subs being taken out of service?
Section G.3: What is the future of US ballistic missile subs (SSBN)?
Section G.4: What happened to USS Thresher and USS Scorpion?
Section G.5: Can someone list accidents involving nuclear submarines?
Section G.6: The Seawolf class
Section G.7: Salvage of German WWII U-Boats
Section G.8: US Covert operations submarines
Section G.9 Why don't the US, UK and France use diesel-electric subs?
Section G.10: The Russian 200 knot torpedo
Section G.11: Soviet/Russian "Akula" and "Typhoon" classes
Section C.12: Project Jennifer, Glomar Explorer, HMB-1, and the "Golf"-class SSB

Section G.1: How are old nuclear submarines being disposed of?

Disposal of nuclear-powered submarines has become a major issue. When nuclear-powered submarines were first built, little thought was given to disposing of the reactors at the end of the submarines' service life. It was generally assumed that the reactors could simply by dumped at sea. The United States disposed of the original reactor from Seawolf (SSN 575) at sea; the Soviet Union disposed of several reactors in the same way. Many old submarines were laid up in reserve, with their reactors in place, pending a suitable means of disposal. Now the US Navy has a comprehensive disposal program for nuclear submarines, and Russia is taking the first steps towards disposing of their old nuclear submarines. Nation by nation, the disposal picture is as follows:

Section G.2: Why are relatively modern subs being taken out of service?

Much controversy has been generated over the decommissioning of several classes of relatively modern submarines. Particularly controversial is the decommissioning of some Los Angeles (SSN 688) class submarines. 11 of these submarines have been decommissioned to date. They are being decommissioned as they come due for mid-life overhauls and refuelings. The cost of the overhauls/refuelings is considered to be excessive in light of the reduced force-level goals for submarines. Each overhaul/refuel would cost at least $250 million, a cost the Navy does not feel is justified in the current political, economic and military climate.

Some earlier submarine classes, in particular the Sturgeon class, were decommissioned for similar reasons, while older classes were simply at the end of their service lives and were due for replacement.

With the drawdown in submarine force levels slowing, the rate of decommissioning has also slowed, and refuelling overhauls are once again being funded.

Section G.3: What is the future of US ballistic missile subs (SSBN)?

The Ohio class currently consists of 18 submarines (SSBN 726-743), The first 8 submarines (SSBN 726-733) are equipped with 24 Trident I/C-4 missiles; the other boats have 24 Trident II/D-5 missiles. Previously, planning called for keeping all 18 boats in service. The original plan was to refit all 8 C-4 boats with D-5 missiles, but after the Cold War it was decided to cancel the C-4 to D-5 refit.

Under the Nuclear Posture Review, it was decided that the first 4 boats (SSBN 726-729) would be withdrawn from strategic service, and the 4 other C-4 boats (SSBN 730-733) would be upgraded to D-5 missiles. The 14 remaining SSBNs would provide the bulk of US strategic/nuclear forces, with up to 2,688 warheads under START (Strategic Arms Reduction Treaty) I, or 1,750 warheads (of 3,500 total) under START II.

The fate of the first 4 Ohios (SSBN 726-729) in uncertain. The only modification currently planned is to render them "non-accountable" under START. This means the vessels will be permanently removed from the strategic role, so they will no longer fall under the provisions of the START I/II treaties. If the boats are retired, this "modification" would probably will consist of filling the missile tubes with concrete and destroying the missile fire control systems.

Various concepts for re-use or conversion of the first four Ohios are being studied. Most of these concepts involve conversion to a guided missile configuration (SSGN), with several vertically-launched Tomahawk cruise missiles in each (former) Trident tube. Most SSGN plans also include provisions for carrying SEALs and their equipment, in effect replacing the current special warfare subs. Although this conversion is not funded in any current shipbuilding plan, it is still being actively considered, and may receive funding in the future.

Section G.4: What happened to USS Thresher and USS Scorpion?

USS Thresher (SSN 593) was lost 10 April 1963 off the New England coast. All 112 naval personnel and 17 civilians aboard were killed. The vessel was on post-overhaul trials, operating from Portsmouth (NH) Naval Shipyard. The submarine was in communication with a surface vessel during her loss. It is believed that her reactor shut down during deep diving trials; she then attempted to blow her tanks to surface, and the expanding air from the tanks froze the air lines. She could not surface with the reactor shut down (reportedly it would take 45 minutes to restart such a reactor) and the air lines frozen. The cause of the reactor shutdown is not known. Thresher was crushed by water pressure as she sank. USS Mizar (AGOR 11) located the wreckage of the submarine in 1964; the site has been surveyed several times since then.

USS Scorpion (SSN 589) was declared lost 6 June 1968. It was determined (presumably by examination of SOSUS tapes or other evidence) that she was lost on 22 May 1968, 400 miles southwest of the Azores. All 99 men aboard perished. Like Thresher, she was crushed by water pressure as she sank. Mizar located the remains of the submarine; the site has been surveyed several times. Scorpion was carrying nuclear weapons at the time of her loss.

The exact cause of the loss is not publicly known. If the Navy has determined the cause, they've kept it secret. The most popular theories involve some form of torpedo malfunction, with resulting internal or external explosion, but there is continued debate and discussion on this issue. It is likely that the cause will never be known with certainty.

Section G.5: Can someone list accidents involving nuclear submarines?

This question is often asked, but nobody can give a complete answer. The details of nuclear submarine accidents are generally highly classified. Anybody who knows the details of an accident isn't (or shouldn't be) talking. In many cases the details of an accident may not be known at all, as it's hard to know what caused the loss of a submarine that simply vanished. Most information about submarine accidents is taken from newspaper and magazine articles, friend-of-a-friend stories, and the like. These sources are generally subject to errors and omissions, so the whole story may not be available, or accurate. In general, stories about submarine accidents that have been posted in the newsgroup seem to be equal parts fact and fiction

Section G.6: The Seawolf class

The Seawolf class is the subject of much controversy and uncertainty. The project started in 1982, designated SSN-21 to mean "attack submarine for the 21st century". It was planned to build three or four submarines per year during from 1989 to 2000, for a total of 29 submarines at a total cost of $36 billion. The submarines were to be faster than the Los Angeles class, restoring the speed lost to gradual hull growth over the past decades. They were to have the Submarine Advanced Combat System (SUBACS), later redesignated BSY-1 and BSY-2. They were to have a silent speed of 20 knots and a deeper operating depth than previous submarines.

These advances lead to high cost and high technical risk. The SUBACS/BSY system has experienced a very troubled development, leading to delays in the later Improved Los Angeles (688I) class submarines, and to delays in the SSN-21 program. The SSN-21 hull is built of HY-100 steel, which lead to welding problems and more delays. The research & development and construction costs have increased steadily.

The name Seawolf was selected in 1986, prior to the striking of the previous Seawolf (SSN 575). The Navy decided to use the program name (SSN-21) as the designation for the first ship, with later boats to follow in that series. This violates the submarine numbering sequence established in 1920. Seawolf should have been designated SSN 774, in keeping with the established numbering sequence.

The program reached maturity as the Soviet Union collapsed, defense spending declined, the 600 ship fleet goal died, and the entire political/military/economic climate changed, so it has been very hard to justify the cost of the Seawolf class vessels. After much argument and many changes, only three submarines will be built:

Name            Number     Completed
Seawolf         SSN 21     1997
Connecticut     SSN 22     1998 
Jimmy Carter    SSN 23     2004 (planned)
Jimmy Carter is being modified to perform "special missions", as a replacement for Parche (SSN 683). This modification includes the addition of a 'midships section to accommodate underwater vehicles and equipment.

Section G.7: Salvage of German WWII U-Boats

In 1995 it was announced that about 100 German WWII U-boats would be salvaged off the Scottish coast. These submarines were scuttled after the end of the war during Operation Deadlight, the disposal of the captured U-boat fleet. Because they were scuttled, there is no issue of them being war graves, as vessels sunk in combat would be. The reasons behind the salavge have been questioned, as raising a batch of U-boats doesn't seem to be a particularly economical way of getting scrap metal. In reality, the ship are not being salvaged to be cut up and melted down as ordinary scrap. These U-boats represent one of the last readily available sources of non-radioactive steel, and are being salvaged for that "clean" steel.

All steel made since the detonation of the first atom bomb in 1945 has contained tiny amounts of radioactivity. This is because the atmosphere now contains trace amounts of radioactivity. The steelmaking process involves the use of large amounts of air, which transfers the radioactivity to the steel. Instruments and equipment used for measuring radioactivity must be free from extra background radiation, so post-1945 "new" steel cannot be used for these purposes. Instead, pre-1945 "clean" steel is used. The steel is obtained from the scrapping of pre-1945 ships, and a considerable amount has been obtained from the German ships scuttled in Scapa Flow at the end of WWI. Obviously, steel obtained from these relatively limited sources is much more valuable than normal steel. The existing sources for "clean" steel have mostly dried up, so the salvage of the U-Boats is economically justifiable now. The submarines will not be melted down after salvage, rather, plates cut from the hulls will be used in their current form.

However, since the announcement of the salvage rights in 1995, everything has grown quiet, and there may be no actual salvage activity, now or in the future.

Section G.8: US Covert operations submarines

Over the years the US Navy has operated a variety of submarines in various covert or secret roles. Some vessels were extensively converted for the role, others were modified slightly, and some were essentially unmodified. It should be noted that many details related to the more modern special missions submarines have NOT been released; the data given here is based on the best published reports.

Section G.9: Why don't the US, UK and France use diesel-electric subs?

(Note - The US retains two diesel-electric subs, one as an experimental craft and one as a training target; the UK has no diesel-electric subs; France retains only one diesel-electric sub, as an experimental platform.)

It is generally considered that the US and UK don't operate diesel-electric submarines because the nuclear propulsion/nuclear submarine (SSN) communities don't want anything to compete with their SSNs for budget dollars. With the SSN community opposed to SSs, such vessels stand very little chance of being built or remaining in service. However, in addition to the political/budgetary issues, there are some valid reasons for not using diesel boats (SSs).

Most importantly, the missions for which the diesel boats are best-suited have vanished from planning since the end of the Cold War. SSs are well suited to defending friendly ports and lurking off enemy ports, waiting for enemy vessels to present themselves as targets. Now there is no enemy to defend friendly ports against, nor are there enemy ships to ambush. Current naval missions are rapid-intervention operations, which take place in distant places on short notice. SSs lack the sustained high speed capability required to reach the scene of an operation in a timely manner. If the submarine can't get there, it simply isn't useful. Even the focus on "littoral operations" doesn't mean SSs are the solution: those littorals are scattered all over the world, far from where the submarines are based. A small-ish SSN can work in the littorals nearly as well as an SS, and it can get there quickly.

In the case of the US and France, the existing non-nuclear submarines were worn out by the late 1980's, and the cost of designing and producing a new class of SSs would have been prohibitive. Adding a new type of submarine costs a lot in terms of training, logistics and maintainance, in addition to the cost of designing, building and operating the vessels. SSs are relatively limited in the types of missions they can undertake, while SSNs are quite flexible. In a time of reduced budgets and smaller fleets, multimission vessels will be preferred over special-mission vessels in almost all cases. The special capabilities of SSs (i.e. ASW training, extremely quiet littoral operations) are not worth the additional financial, logistical, maintainaince and training costs SSs would bring.

SSs are, however, well suited for nations with primarily defensive concerns (i.e. Japan, Australia), and they're better than nothing for nations without the money, technical expertise or trained crews required to operate nuclear submarines. The US, UK and France aren't among these nations.

Section G.10: The Russian 200 knot torpedo

People frequently ask about a "200 knot torpedo" they have heard about, thinking it is a very fast torpedo of conventional type. This is not the case. Quoting from Conway's Fighting Ships of the World, 1947-1995: "Shkval is a recently-developed rocket torpedo which a submarine is expected to fire back when it detects an oncoming weapon. The cone-shaped Shkval travels within a supercavitating bubble which it produces with its own exhaust. It is fired as a conventional torpedo, and ignites its rocket after travelling 50 m from the submarine. Range is given as 6 nm at 200 knots. Running depth is 400 m. Dimensions: 53 cm x 8.2 m. The warhead is nuclear, with a preset burst range. The published designations are VA-111 and M-5."

Section G.11: Soviet/Russian "Akula" and "Typhoon" classes

There is considerable confusion surrounding the class names for the Soviet/Russian submarines commonly known as the "Akula" and "Typhoon" classes. This confusion arises from the fact that there are two sets of class names for these ships - the names assigned by NATO, and the actual Soviet/Russian names.

The class known to NATO as "Akula" is a modern attack submarine (SSN). The Soviets identified this class as Shchuka-B; in addition the class name Bars is sometimes associated with these ships.

The class known to NATO as "Typhoon" is an extremely large ballistic missile submarine (SSBN). This is the class made famous by the book and movie Hunt for Red October. By an odd coincidence, the official Soviet name for this class is Akula!

Thus, there are two very different classes associated with the name "Akula".

Section G.12: Project Jennifer, Glomar Explorer, HMB-1, and the "Golf"-class SSB

Project Jennifer was the codename applied to the CIA project that salvaged part of a sunken Soviet submarine in 1974. The Soviet "Golf"-class ballistic missile submarine (SSB) K-129 sank off Hawaii on 11 April 1968, probably due to a missile malfunction. The "Golf" class submarines were diesel-electric ballistic missile subs, a modified version of the "Foxtrot" class submarines. They carried 3 SS-N-5 SLBMs in an elongated sail structure.

The sunken submarine was located in 16,500 feet of water. Mizar (AGOR 11) took part in the search, as did the specialized "research" submarine USS Halibut (SSN 587).

The CIA ran an operation to recover the sunken submarine. The recovery effort centered on Hughes Glomar Explorer, a 63,000 ton deep-sea salvage vessel built for the progect. The ship was built under the "cover story" that she was a deep-sea mining ship, intended to recover "manganese nodules" from the ocean floor. The ship was supposedly being built for the Summa Corporation at the direction of Howard Hughes for use by his Global Marine Development Inc. At the same time the "Hughes Mining Barge" was built. The barge, commonly known as HMB-1, was a submersible barge intended to carry the "claw" to be used in the recovery effort.

Hughes Glomar Explorer was equipped with a massive hoisting mechanism amidships, and a "moon pool" - a large internal underwater hangar to provide access to the ocean. The submarine was to be hoisted into the moon pool by a massive claw, which was stored in HMB-1. After Hughes Glomar Explorer and HMB-1 left port, the barge submerged, manuvered under Glomar Explorer, and the claw was hoisted into the moon pool in preparation for the salvage lift.

Glomar Explorer arrived on the recovery site 4 July 1974 and conducted salvage operations for the next month. During the salvage effort (according to the story released to the public), only the forward 38 feet of the submarine was recovered. The section included two nuclear-tipped torpedoes, various cipher/code equipment and 8 dead crewmen. The recovered section was brought into the ship's moon pool, where it was analysed and dismantled. The dead Soviet sailors were buried at sea.

There is continued speculation about what was really recovered, but the real answers are, of course, highly classified. It is clear, however, that the intact submarine would have been much longer than Glomar's "moon pool", so it would not have been possible to bring the entire submarine aboard. It is also clear that the CIA knew the condition of the submarine, leading to speculation that the submarine was broken in two (or more) pieces, with the moon pool built to accommodate the largest pieces. It is also possible that the submarine was intact, and the CIA planned to cut off the bow and stern prior to bringing the sub into the moon pool.

After the recovery, Hughes Glomar Explorer was transferred to the Navy on 3 Sept 1976 and designated AG 193. The vessel is not officially assigned a name, but is commonly referred to Glomar Explorer. She was transferred to the Maritime Administration on 17 Jan 1977 and laid up at Suisun Bay, CA. The Navy attempted to sell the ship, but failed. In June, 1978 she was leased to Global Marine Development Inc. for commercial use. That lease was terminated in 1980. In 1979 it was proposed that the ship be transferred to the National Science Foundation for use as a deep-sea drilling ship, but that effort was not funded. The ship was returned to Navy custody on 25 April 1980 and transferred to the Maritime Administration on the same day for continued layup at Suisun Bay. She remained in layup for the next 16 years. During August, 1996 it was announced that Global Marine had leased Glomar Explorer from the Navy for 30 years. The ship left the mothball fleet 5 November 1996 to be totally reconditioned and converted to a drill ship. She now operates in the Gulf of Mexico, drilling test oil wells. During the conversion some 11,000 tons of steel, including virtually all equipment and facilities related to her salvage role, were removed.

HMB-1 was laid up after the recovery, but was transferred to the Environmental Protection Agency at some point. She was returned by the EPA in 1982, officially to be laid up in reserve. It now seems likely that it was then employed as the "mother ship" for the stealth ship Sea Shadow, a purpose for which it was employed during the 1990's. At some point HMB-1 was converted from an submersible barge (with access via a top hatch) into a covered floating drydock (with an end door).

Back to the FAQ Archive Page

This FAQ created and maintained by Andrew Toppan
Copyright © 1997-2003, Andrew Toppan.
Reproduction, reuse, or distribution without permission is prohibited.