New US "Super-Carriers" being built as we speak New US "Super-Carriers" being built as we speak
New US "Super-Carriers" being built ... 
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Expendable carriers currently taunting Iran
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Design & Preparations Continue for t... befurther
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Some nations have aircraft carriers. The USA has super-carriers. The French Charles De Gaulle Class nuclear carriers displace about 43,000t. India’s new Vikramaditya/ Admiral Gorshkov Class will have a similar displacement. The future British CVF Queen Elizabeth Class and related French PA2 Project are expected to displace about 65,000t, while the British Invincible Class carriers that participated in the Falklands War weigh in at just 22,000t. Invincible actually compares well to Italy’s excellent new Cavour Class (27,000t), and Spain’s Principe de Asturias Class (17,000t). The USA’s Nimitz Class and CVN-21 Gerald R. Ford Class, in contrast, fall in the 90,000+ tonne range. Hence their unofficial designation: “super-carriers”. Just one of these ships packs a more potent air force than many nations.
As the successor to the 102,000 ton Nimitz Class super-carriers, the CVN-21 program aims to increase aircraft sortie generation rates by 20%, increase survivability to better handle future threats, require fewer sailors, and have depot maintenance requirements that could support an increase of up to 25% in operational availability. The combination of a new design nuclear propulsion plant and an improved electric plant are expected to provide 2-3 times the electrical generation capacity of previous carriers, which in turn enables systems like an Electromagnetic Aircraft Launching System (EMALS, replacing steam-driven catapults), Advanced Arresting Gear, and integrated combat electronics that will leverage advances in open systems architecture. Other CVN-21 features include an enhanced flight deck, improved weapons handling and aircraft servicing efficiency, and a flexible island arrangement allowing for future technology insertion. This graphic points out many of the key improvements.
DID’s CVN-21 FOCUS Article offers a detailed look at a number of the program’s key innovations, as well as a list of relevant contract awards and events.
The Nimitz Class was designed in the 1950s and 1960s, and despite a number of equipment changes since then, the basic design remains. Rear Adm. Dennis M. Dwyer, the Navy’s program executive officer for aircraft carriers, put it this way in a May 2003 National Defense Magazine article: “If you take the time period between Nimitiz and CVN-21 [design], it’s the same time period between [the USS] Langley (CV 1) – the first carrier – and Nimitz.” The Langley was commissioned in 1922.
The technological jump is much shorter. Aircraft carriers are a mature technology, and CVN-21’s refinements are more about marginal improvements to effectiveness, cost-efficiency, and future upgradeability than any revolution in carrier design.
Even so, creating a new ship class isn’t cheap. According to NAVSEA, the cost of the initial design work to create the CVN-21 ship class and develop its new technologies is projected at $5.6 billion. Building the CVN 78 Gerald R Ford will cost an estimated $8.1 billion, and advance construction is beginning in 2005. This allowed shipbuilders to test the design-build strategy before overall construction kick-off in 2007. The USS Gerald R Ford will be the first true CVN-21 Class ship, though the transitional Nimitz Class CVN 77 George H. W. Bush will incorporate some elements like upgraded navigation and communications systems, improved air defense armament and ECM, a new fuel system for aircraft fuel, et. al.
DID investigated the CVN-21’s exact build cost, and the future operating cost savings expected as a result of its design innovations. Essentially, CVN-21 carriers are expected to generate savings in two major ways.
One is through an array of design and automation changes to various areas of the ship that reduce the required number of sailors aboard.
The other is through reduction in the number of major maintenance overhauls required. NAVSEA expects these changes to save $5 billion per ship over the ships’ projected 50-year lifetime.
Meanwhile, measures are being taken aimed at improving the carriers’ effectiveness and survivability. Some of these changes include:
An electromagnetic aircraft launching system (EMALS) will replace the steam-powered system used on current ships. The current steam catapults are large, heavy, and operate without feedback control. They impart large loads to the airframe via sudden shock, and are difficult and time consuming to maintain. Additionally, the trend towards heavier, faster aircraft will soon result in energy requirements that exceed the capacity of steam catapults.
EMALS offers a 30% increase in launch energy potential, as well as substantial improvements via reduced weight, smaller volume, and more flexibility; plus increased control, availability, reliability, and efficiency. Self-diagnostics can be embedded in it, simplifying maintenance. The other thing that simplifies maintenance is the removal of the 614 kg of steam required for each aircraft launch, plus hydraulics and oils, water for braking, and associated pumps, motors, and control systems. A corresponding Advanced Arresting Gear (AAG) system will replace existing Mk7 hydraulic motors with a system based on electric motors, in order to handle the arresting wires used to catch aircraft tailhooks on landing.
Because an EMALS-based system will take up far less space, it also provides design flexibility. EMALS launchers can be moved far more easily, downsized and incorporated into a ramp to provide additional launchers for short take-off aircraft, etc. Finally, its steadier acceleration reduces launch strains on naval aircraft, which helps extend their airframe life. That isn’t calculated as part of cost savings for the ship, but it definitely adds up over time.
Because EMALS is such a big change from existing steam-driven catapult systems, it is a critical technology for the CVN-21 Class, whose progress or lack thereof will have a substantial effect on the ships’ on-time delivery and ability to fulfill their cost promises.
A redesigned nuclear reactor is expected to supply 25% more power for propulsion, but require only 50% the maintenance costs and a 50% reduction in sailors required to operate it. Removing the steam catapults in favor of EMALS is synergistic, reducing work on the maintenance-heavy steam conduits and allowing the steam from the nuclear reactor to do other things – like make electricity. The CVN-21 Class is expected to have 3 times the electricity generating capacity of the Nimitz Class. If our personal experiences with power hungry electronics over the last 20 years are anything to go by, they may need it.
The new reactor adds another, very important advantage: it will not need refueling during the ship’s life-cycle, which is currently a multi-year, multi-billion process.
Advanced arresting gear. The Naval Air Systems Command, headquartered at Patuxent River Naval Air Station, is working on an improved system for trapping aircraft as they land and hook the arresting cables. This electrical-hydraulic combination will be designed to be able to handle emerging platforms, such as the F/A-18E/F Super Hornet and F-35C Joint Strike Fighter, which are heavier and able to return to the ship with more unexpended munitions than their predecessors.
Rear Adm. Dwyer has estimated that these changes will enable the size of the CVN-21 ships’ crews to be reduced from about 3,000 to 2,500 and possibly as low as 2,100. Note that some 2,500 personnel are also carried in the air wing, and will not be subject to reductions from any of the methods described here.
The CVN-21 class will also feature effectiveness improvements.
Dual-Band Radar. This was pioneered on the Zumwalt class DDG-1000 destroyers. Most warships carry 2 radars with very different functions. The volume search radar performs wide area scans over a large footprint, while the targeting and fire control radar guides missiles and other weapons fired by the ship. They are integrated at the combat system level, but each is a separate sub-system, operating in different bands with different detection strengths. The DBR approach integrates both a SPY-3 active-array X-band radar for excellent fire control against saturation attacks, and an active array S-band radar for wide area search and performance in clutter, in order to provide a single combat picture with fewer coverage gaps and better response. All in less space than existing systems, allowing designers to shrink the “island” tower on deck.
The use of active-array, digital beamforming radar technology will help DBR-equipped ships survive saturation attacks, since they can allocate emitters to track and guide against tens of incoming missiles simultaneously. Active array radars also feature better reliability than mechanically-scanned radars, and recent experiments suggest that they could have uses as very high-power electronic jammers, and/or high-bandwidth secure communications relays. Read “The US Navy’s Dual Band Radars” for full coverage.
Electronic upgradeability. CVN 21 will also employ an integrated warfare system that allows its electronics to slot into a single, open-architecture, scalable weapons system, based on commercial, off-the-shelf technologies. Dwyer noted that the US Navy would like everything to “plug and play.” While technology never works quite that way, the process can be made easier – and doing so would improve long-term performance. As Rear Adm. Dwyer pointed out:
“Right now, the way we build aircraft carriers is to buy all the electronic equipment up front, then take seven years to build a ship and deliver it with obsolete electronics. It’s kind of crazy now that you think about it. We don’t want to do that any more… What we’d like to do is put the electronic equipment in separately from the actual shipbuilding process.”
Along similar lines, CVN-21 will feature a so-called smart deck, equipped with redundant and flexible fiber-optic cable that is easier to move and repair than hard copper wiring. It can be blown through the ship for installation – and more easily reeled out for replacement. Its capacity is also easier to upgrade, by clipping on terminating devices that allow for richer exploitation of different electromagnetic bandwidths of light.
A NASCAR flight deck philosophy. The “island” tower on the flight deck is being redesigned, reduced, and moved. As Rear Adm. Dwyer noted: “The people who actually handle aircraft said, ‘The island’s in the wrong place. It makes the aircraft all jam up. Why don’t you move it?’” So the island has shifted 100 feet aft, and the carrier’s elevators, deck et. al. are being shifted to a racetrack-like pattern of operations, complete with “pit stop” parking et. al.
It is this system that accounts for the expected improvements in operational flights per day – a key measure of the carrier’s ability to both project power and defend itself.
Survivability also received attention. While the bridge and flight deck operations will remain on the island, the carrier’s command and decision centers are being moved from the island, to a “smart deck” down lower in the ship. This places them somewhere that’s both safer, and less in the way of aircraft operations. Meanwhile, the fuel tanks and bomb/ missile/ ammunition magazines are getting more armor, and the hull is being reinforced.
The improvements described above are large leaps. To help with this transition, the USS George H.W. Bush was designed as a transitional ship between the Nimitz Class and the Ford Class. As such, CVN 77 has been a candidate for development, evaluation, and incorporation of a range of advanced technologies and acquisition reform initiatives. The hope is that these initiatives would result in lower life cycle costs, and also set the standard by which further improvements in the CVN-21 Class will be measured.
The carrier is currently under construction by Northrop Grumman Newport News, and is scheduled to enter service in 2009. Technology innovations fielded in CVN 77 are targeted to achieve a 15% reduction in Operation and Support Costs, and they will also be backfit as feasible in the other nine ships of the Nimitz Class through the Carrier Improvement Plan. The carriers’ mid-life refueling overhauls and refit are the most likely time, given the scale of effort required.
Some cost-saving transitional features and improvements designated for this last ship of the Nimitz Class will include:
The George H.W. Bush was originally scheduled to be finish construction in April 2008, but delays pushed the timeline back to about March 2009, and increased costs from $5.9 billion to $6.2 billion in appropriation-year dollars. The Newport News Daily Press reports that CVN 77 was commissioned on Jan 10/09 at NAS Norfolk, despite being approximately 3-4 months away from the point at which it would normally be considered ready. The ship was towed into place for the ceremony, whose date was set in order to commission the ship while its namesake’s son was still President. In practice, however, this meant that the Navy accepted the ship even though it had never tested its major operating systems or nuclear reactors at sea.
The ship went on to pass its sea trials in February 2009.
The USA’s carrier replacement project has been underway at some level for many years now. Activity can easily trace back to 1994, and really kicked off in 1997 when the Naval Research Advisory Committee (NRAC) was asked to study technology opportunities that might be useful in “CVX.” From that moniker, the effort evolved to become the “CVN-21 Carrier Replacement Program.” As the ships are built and fielded, however, more and more references will be made to the CVN-78 Gerald R. Ford Class instead.
Long-lead appropriations for the Gerald R. Ford [CVN-78] began in 2001, and long-lead appropriations for the unnamed CVN 79 are already underway. Beyond that, construction of additional carriers becomes less certain. Current Pentagon plans call for a “drumbeat” of one new carrier every 5 years, which slows planned construction, raises per-ship costs by adding more fixed costs, and also imposes additional costs by requiring more re-designs for new electronics etc. with each new ship. The USA’s rapidly-deteriorating fiscal situation are throwing even that plan into difficulty, however, even as advances in ship-killing missiles are calling the large aircraft carrier’s pre-eminence into question.
Purchases of something as expensive as a super-carrier take time, and are spread over many annual budgets. First, finished items like engines, which must be present at early stages of construction, are bought as “long-lead” materials, along with some advance sub-assembly work. Then full construction funding is appropriated over several years. Recent budgets include:
FY 2002: $623.4 million – $306.3 million RDT&E, $317.1 million procurement.
FY 2003: $855.3 million – $371.6 million RDT&E, $483.7 million procurement.
FY 2004: $1.469 billion – $306 million RDT&E, $1.163 billion procurement.
FY 2005: $975.3 million – $351.7 million RDT&E, $623.6 million procurement.
FY 2006: $1.063 billion – $300.5 million RDT&E, $762.5 million procurement.
FY 2007: $1.415 billion – $307.8 million RDT&E, $1.107 billion procurement
FY 2008 request: $3.081 billion – $232.2 million RDT&E, $2.848 billion procurement begins funding full construction of CVN 78.
FY 2009: $4.094 billion – $171.8 million RDT&E, $3.916 billion procurement.
FY 2010: $1.396 billion – $175.8 million RDT&E, $1.22 billion procurement.
FY 2011 request: $2.734 billion – $93.8 million RDT&E, $2.64 billion procurement.
FY 2012 request: $554.8 million.
The target date for CVN 78 commissioning is 2014, whereupon it will replace America’s first nuclear-powered aircraft carrier – the 50+ year old USS Enterprise (CVN 65). CVN 78 is also expected to serve for 50 years, from 2014-2064.
Newport News is designing the new ships using a 3-D product model tool called CATIA (Computer-Aided Three-Dimensional Interactive Application), a widespread standard for advanced design in the shipbuilding industry that is also in widespread use by the global auto industry. They’re also using CAVE, (Computer-Aided Virtual Environment), a 3D immersive environment tool used for viewing certain areas of the CATIA product model, and refining the construction strategy.
Read More:
www.defenseindustrydaily.com/design-preparations-continue-for-the-usas-new-cvn21-supercarrier-01494/
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