SEAL Submarine

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Navy Seal Submarine


You won’t find it at the Navy Seals online shop, nor will you find it listed as a standard piece of equipment by the United States Navy, but the mini-sub called the Advanced SEAL Delivery System (ASDS) continues to be improved by the Navy and U.S. Special Operations Command (SOCOM) in the hopes of rescuing an incredible budget overrun for an amazing little one-of-a-kind submarine.
Problematic Beginnings
  • First conceptualized in 1983, and later contracted out to Northrop Grumman in 1994, the Navy Seal special operations submarine (shown above piggy-backed on the USS Greenvile - SSN 772) program has been beset by numerous technical and financial problems. Many of these problems have been blamed on awarding the contract to Northrop Grumman, an aircraft builder, which had never before built a submersible. In 2003 the Congressional Budget Office (CBO) issued a report citing two significant technical problems:
    1. Propellers - The original design for the mini-sub included propellers that caused too much noise during operation due to axial movement in the shaft causing significant vibration. The solution to this problem was a newly developed propeller made of composite materials.
    2. Batteries - The second major problem with the design was the silver-zinc batteries which did not hold a charge as well as the navy had originally planned. The engineers have been replacing the old batteries with new more reliable lithium-ion batteries.
    In addition, the ASDS submarine has been plagued by wiring problems as well as problems with the tail section distorting due to large flow stresses (resolved by removing the aluminum tail and replacing it with a titanium tail).
    Worse, the submarine has experienced extreme cost overruns. Originally the per-item cost was planned to be around $80 million per sub. However, the cost for the first boat has grown to over $446 million. This is particularly disturbing since the entire project cost was supposed to be only $527 million for six boats (now the projected cost is over $2 billion). In addition, the first boat was not delivered until three years after the original year 2000 target.
Difficult Design Specifications

  • The ASDS was originally planned to supplement or replace the smaller and less versatile Swimmer/SEAL Delivery Vehicle (SDV) by providing longer range and faster speeds. In addition, the ASDS inserts SEALS into the operational environment with a higher degree of readiness and therefore effectiveness by reducing fatigue (never mind the infamous training regime, swimming long distances in cold water will take it out of anyone even a Navy SEAL) and increasing the amount of equipment the SEALs can bring with them. Finally, the platform allows for more effective shore recon before insertion.
    To fulfill this role the original bid for the ASDS had a number of important requirements.
    • The ability for the submarine to have enough battery power to traverse long distances.
    • The Navy specified that the device and all internal equipment be able to handle four g’s acceleration to increase it’s ability to handle underwater shock.
    • It was to have a low acoustic signature to help it slip unnoticed into protected environments guarded by sonar.
    • It had to be small enough and light enough to be attached to a 688 (Los Angeles) class submarine.
    • It must be designed to anchor to the ocean floor between 2 and 190 feet and “lock-out” the SEALS to move them from a dry environment to the ocean without flooding the ASDS.
    • It was to have unique life support systems, larger than those for similar sized vehicles, were required to transport an entire SEAL platoon (16 men) to their destination along with the two sub drivers.
    • A sonar system was necessary that could be fitted to the small boat but still provide for shallow water maneuvers.
    • The ASDS had to be capable of traveling to the maximum depth of 800+ feet of the Los Angeles-class submarine upon which it was designed to travel.
    • The ASDS was to have a Dry Dock Shelter (DDS) allowing for waterless access to the host submarine.
    • It was to have installed a full communications package similar to that of a Los Angeles-class attack submarine.
    • The sub also has a built-in hyperbaric compression chamber.
    • Finally, the ASDS was designed to use a “unique electro-optical system [to] provide a new level of undersea situational awareness”.
First Deployment
  • asds.jpg
    The single sub purchased by the Navy became operational in 2003 at its home base, Pearl Harbor, with
    SEAL Delivery Vehicle Team One (SDVT ONE).
    The new submarine was first deployed in 2003 piggy-backed on the USS Greeneville during its patrols of the Indian Ocean and the Persian Gulf as part of the unique battle-ready Expeditionary Strike Group (ESG) 1. [The mini-sub can also be docked onto the USS Charlotte submarine. Four Trident subs are also being refit to dock with the ASDS.]
    As part of the ESG the ASDS submarine was considered an important part of the Navy’s ability to wage the war on terrorism and valuable addition to the ESG when the USS Greenville was attached to the group:
    “It’s the right ship at the right time. It has the unique ability to carry and deploy ASDS. If you look at all the different types of ships, the submarine is most suited for littoral operations. The submarine and special operations forces are the premiere stealth forces in our military that we can use fight the Global War on Terrorism.” - Rear Admiral Paul Sullivan, Commander, Submarine Force, U.S. Pacific Fleet
    However, when the Greeneville set sail from Pearl Harbor on September 3, 2003 the ASDS was not attached to the larger submarine. It was not until the Greenville arrived at Guam in early November that the ASDS loaded onto her back (the 60-ton ASDS is also transportable by the C-5 Galaxy and the C-17 Globemaster).
    Navy documents show, however, that there is more than a weight and maneuverability cost to the host submarine. Once in Guam the Greeneville off-loaded 12 TLAMs (Tomahawk Land Attack Missile) and 1 ADCAP (MK-48 torpedo) to allow for additional berthing and stowage space in the torpedo room. The removal of the ordinance resulted in a weight savings of 38,495 for the Greenville.
    On November 9th 2003 the Greenville, under command of Commander Lindsay R. Hankins, and the ASDS commenced Exercise Piranha Fury 04-1. Piranha Fury was deemed a “proof-of-concept” exercise intended to, “demonstrated the ability,of the ASDS Platoon and a submarine to load out and operate ASDS in a forward deployed environment. The exercise was successful and GREENEVILLE returned to Guam on 4 December,” according to the official USS Greeneville command history for 2003. After arrival in Guam the ASDS was off-loaded and the Greeneville transited to Stirling, Australia.
Bringing a Halt to the Project
  • In April of 2006 the Pentagon dropped plans for purchasing additional subs and stopped work on the program. However, the Navy and U.S. Special Operations Command were directed to continue work on the one sub that had been delivered in the hopes of increasing its performance and reliability.
Navy Seal Submarine Specifications

  • Length overall: 65 ft
  • Beam: 6.75 ft
  • Height: 8.25 ft
  • Displacement: 55 tons
  • Propulsion 67 hp electric motor (Ag-Zn battery) driving a single propeller
  • Max. Speed: 8+ knots
  • Range: 125+ mi.
  • Max. Diving Depth: classified (see above)
  • Accomodations: 2 Crew + up to 16 SEALs, depending on equipment
  • Sonar: Forward Looking - detect natural/man-made obstacles, Side Looking - terrain & bottom mapping, mine detection
If they've cancelled the program then what the heck did I see from my lanai? Can you find the articles? Because that would be interesting to read.

I can see SDV-1 from my apartment. It's amazing to have morning coffee, watch the subs cruise around, Navy ships docked, fighters getting flight time at Hickam, all at once...
Here, pretty od:

Mini-sub plan scuttled
Though the Navy still needs small special operations submarines, the Pentagon has canceled the program to build them, citing reliability concerns.
April 14, 2006
The Pentagon has scuttled a program to build small submarines to carry special operations forces on covert missions - axing an effort that has struggled with cost overruns and mechanical problems.

Citing "performance and reliability issues," the Defense Department cut its losses in the Advanced Seal Delivery System after only one of the six submersibles was built. The first boat, meanwhile, is not being used on missions because it is not deemed safe for crewmembers. Costs on the first sub have nearly tripled, to $446 million, from original estimates 10 years ago, and overruns on the next boats were projected, the U.S. Special Operations Command said.

"The program itself, other than ensuring the reliability of hull one, has been canceled," said Lieut. Cmdr. Steven Mavica, a spokesman with the U.S. Special Operations Command, based in Tampa, Fla.

The decision came even as special operations commanders in the field continue to say they need miniature subs or some other mechanisms to carry Navy SEALs in climate-controlled environments.

With more and more anti-terrorism efforts taking place around shorelines, that demand is expected to only grow.

The Defense Department has directed the Special Operations Command to "take the lead in assessing alternative material solutions" to the fill the gap. It also directed the Navy to keep trying to work out the problems on the first boat.

Though Northrop Grumman Newport News was not leading the effort to build the vessels, the local shipyard had gotten involved in the last year or so.

The Newport News yard, one of two U.S. companies that build larger nuclear-powered submarines, was set to help a Baltimore-based sister company, Northrop Grumman Electronic Systems, in building the second through the sixth boats. Building the hulls on those vessels was to happen at the Newport News site, a job that could have employed up to 150 people here by 2008. The hulls would have been then sent back to a plant in Annapolis, Md., for outfitting.

The miniature subs are designed to be 65 feet in length, eight feet across, weigh 55 tons, have a range of more than 100 nautical miles and carry "more than five" people. They were to ride piggyback atop larger submarines.

The job to build them was awarded to the Westinghouse Electronics, based in Baltimore, a company that was later bought out by Northrop.

But the program to build them has struggled. There were early noise issues, problems with the battery system and tail fatigue.

Last August, during testing and evaluation on the first boat, those on board felt a sudden vibration and heard a sharp noise as it headed back to port. That turned out to be an internal engine problem that triggered the decision to hold off on later boats.

The Government Accountability Office, the investigative arm of Congress, has criticized the small-sub program, citing problems that should have been discovered during development but were learned about only in testing. The program at the time was also six years behind schedule, the report added.

"The program has suffered from insufficient management attention on the part of both the government and contractor, which led to missed opportunities for righting the program as it proceeded," the GAO said.

In light of the program's cancellation, Northrop Grumman Electronic Systems termed the first mini-submarine "an operational asset for the Navy for almost three years," a vessel that has been "an integral part of successful missions."

It was unclear what missions the company was referring to.

Northrop said it is still involved in the "improvement program" for the first boat. "The Navy has confirmed that the need for the capability provided by Advanced Seal Delivery System remains, and Northrop Grumman will closely follow future developments in this area."

Elected officials, including Congressman Robert R. Simmons, R-Conn., had called on the Navy to cancel the mini-sub and re-open solicitations, arguing that General Dynamics Electric Boat, a sub builder in Groton, Conn., would be better at doing the work.
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