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Monday, March 10, 2014

Gerald R. Ford-class aircraft carrier

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PCU Gerald R Ford at shipyard
PCU Gerald R Ford at shipyard
Class overview
Name: Gerald R. Ford–class aircraft carrier
Builders: Newport News Shipbuilding
Operators:  United States Navy
Preceded by: Nimitz-class aircraft carrier
Cost: $11,338.4m (FY14)[1]
Building: 2
Planned: USS Gerald R. Ford (CVN-78)
USS John F. Kennedy (CVN-79)[2]
USS Enterprise (CVN-80)[3]
8[4] more ships (currently unnamed)
General characteristics
Type: Aircraft carrier
Displacement: Approximately:
100,000 long tons
101,600 tonnes
112,000 short tons[5]
Length: 1,106 ft (337 m)
Beam: Flight deck: 256 ft (78 m)
Waterline: 134 ft (41 m)
Height: 250 feet (76 m)
Draft: 39 ft (12 m)[6]
Decks: 25
Propulsion: 2 A1B nuclear reactors
Speed: In excess of 30 kn (56 km/h; 35 mph)
Capacity: Officers: 508
Enlisted: 3789[6]
Armament: Antiaircraft missiles:
2 × RIM-162 ESSM
2 × RIM-116 RAM
Guns:
2 × Phalanx CIWS
4 × M2 12.7mm machine guns
Aircraft carried: 75+
Aviation facilities: 1,092 × 256 foot (333 × 78 m) flight deck
The Gerald R. Ford-class aircraft carrier (or Ford-class) is a supercarrier currently being built to replace some of the United States Navy's existing Nimitz-class carriers. The new vessels will have a hull similar to the Nimitz carriers, but will introduce technologies developed since the initial design of the previous class (such as the Electromagnetic Aircraft Launch System), as well as other design features intended to improve efficiency and running costs, including reduced crew requirement.[7] The first ship of the class, the Gerald R. Ford, has hull number CVN-78.[Note 1][8]

Features summary

Carriers of the Ford-class will incorporate design features including:[9]
The navy believes that with the addition of the most modern equipment and extensive use of automation, it will be able to reduce the crew requirement and the total cost of future aircraft carriers.[13] The primary recognition feature compared to earlier supercarriers will be the more aft location of the navigation "island" to make aircraft movements more efficient.[14] The Ford class are intended to sustain 160 sorties per day for 30+ days, with a surge capability of 270 sorties/day, but the Director of Operational Testing Michael Gilmore has criticised the unrealistic assumptions used in these forecasts and has indicated sortie rates similar to the 120/240 per day of the Nimitz class would be acceptable.[15]

Design and development

The Nimitz-class aircraft carrier has been an integral part of United States power projection strategy since Nimitz was first commissioned. Displacing approximately 100,000 tons when fully loaded, a Nimitz-class carrier is capable of steaming faster than thirty knots, self-sustaining for up to ninety days, and launching aircraft to strike targets hundreds of miles away.[16] The endurance of this class is exemplified by USS Theodore Roosevelt, which spent 159 days underway in support of Operation Enduring Freedom without the need to visit a port or be refueled.[17] Over the lifespan of the class many new technologies have been successfully integrated into the design of this vessel. However, with the technical advances made in the past decade the ability of the navy to make improvements to this class of ship has become more limited. "The biggest problems facing the Nimitz class are the limited electrical power generation capability and the upgrade-driven increase in ship weight and erosion of the center-of-gravity margin needed to maintain ship stability."[18]
With these constraints in mind the navy developed what was initially known as the "CVN-21" program, which ultimately evolved into CVN-78, Gerald R. Ford. Improvements were made through developing technologies and more efficient design. Major design changes include a larger flight deck, improvements in weapons and material handling, a new propulsion plant design that requires fewer personnel to operate and maintain, and a new smaller island that has been pushed aft. Technological advances in the field of electromagnetics have led to the development of an Electromagnetic Aircraft Launch System (EMALS), and an Advanced Arresting Gear (AAG). An integrated warfare system, the Ship Self-Defense System (SSDS), has been developed to support flexibility in adapting the infrastructure of the ship to future mission roles. The new Dual Band Radar (DBR) combines S-band and X-band radar in a single system.[19] With new design and technology the Ford will have a 25% increase in sortie generation, threefold increase in electrical generating capacity, increased operational availability, and a number of quality-of-life improvements.[20] Requirements for a higher sortie rate of around 160 exits a day with surges to a maximum of 270 sorties a day in times of crisis and intense air warfare activity, have led to design changes in the flight deck, which enable greater aircraft launch capabilities.

Flight deck

Artist's concept of CVN-78
Changes to the flight deck are the most visible of the differences between the Nimitz and Gerald R. Ford classes. Several sections have been altered from the layout of the Nimitz-class flight deck to improve aircraft handling, storage, and flow. Catapult number four on the Nimitz-class cannot launch fully loaded aircraft because of a deficiency of wing clearance along the edge of the flight deck.[21] CVN-78 will have no catapult-specific restrictions on launching aircraft, but still retains four catapults, two bow and two waist,[22] and the number of aircraft lifts from hangar deck to flight deck level was reduced from the earlier ships from four to three. The design changes to the flight deck are instrumental in the maximization of sorties launched.
The route of weapons to the aircraft stops on the flight deck has been replanned to accommodate higher rearming rates, and in turn higher potential sortie rates.
Another major change: a smaller, redesigned island will be pushed further back relative to the older classes of carriers. Moving the island creates deck space for a centralized rearming and refueling location. This reduces the number of times that an aircraft will have to be moved after landing before it can be launched again. Fewer aircraft movements require, in turn, fewer deck hands to accomplish them, reducing the size of the ship's crew. A similar benefit is realized by altering the path and procedures for weapons movement by redshirts from storage to flight deck, again potentially allowing the new ship to support a higher sortie rate than the Nimitz-class ship while using fewer crew members than the Nimitz requires. On Nimitz-class carriers the time that it takes to launch a plane after it has landed is set by the time needed to rearm and refuel it. To minimize this time, ordnance will be moved from storage areas to the centralized rearming location via relocated, higher capacity weapons elevators, utilizing linear motors.[23] The new path that ordnance follows does not cross any areas of aircraft movement, thereby reducing traffic problems in the hangars and on the flight deck. According to Rear Admiral Dennis M. Dwyer, these changes will make it hypothetically possible to rearm the airplanes in "minutes instead of hours".[24]

Power generation

The propulsion and power plant of the Nimitz-class carriers was designed in the 1960s. Technological capabilities of that time did not require the same quantity of electrical power that modern technologies do. "New technologies added to the Nimitz-class ships have generated increased demands for electricity; the current base load leaves little margin to meet expanding demands for power."[25] Increasing the capability of the U.S. Navy to improve the technological level of the carrier fleet required a larger capacity power system.
The new A1B reactor plant is a smaller, more efficient design that provides approximately three times the electrical power of the Nimitz-class A4W reactor plant. The modernization of the plant led to a higher core energy density, lower demands for pumping power, a simpler construction, and the use of modern electronic controls and displays. These changes resulted in a two-thirds reduction of watch standing requirements and a significant decrease of required maintenance.[26]
A larger power output is a major component to the integrated warfare system. Engineers took extra steps to ensure that integrating unforeseen technological advances onto a Gerald R. Ford-class aircraft carrier would be possible. The U.S. Navy projects that the Gerald R. Ford-class will be an integral component of the fleet for ninety years into the future (the year 2105). One lesson learned from that is that for a ship design to be successful over the course of a century, a great deal of foresight and flexibility is required. Integrating new technologies with the Nimitz-class is becoming more difficult to do without any negative consequences. To bring the Gerald R. Ford-class into dominance during the next century of naval warfare requires that the class be capable of seamlessly upgrading to more advanced systems.

Launch and landing systems

The Nimitz-class aircraft carriers use steam-powered catapults to launch aircraft. Steam catapults were developed in the 1950s and have been exceptionally reliable. For over fifty years at least one of the four catapults has been able to launch an aircraft 99.5% of the time.[27] However, there are a number of drawbacks. "The foremost deficiency is that the catapult operates without feedback control. With no feedback, there often occurs large transients in tow force that can damage or reduce the life of the airframe."[28] The steam system is massive, inefficient (4–6%),[29] and hard to control.
Control problems with the system results in minimum and maximum weight limits. The minimum weight limit is above the weight of all UAVs. An inability to launch the latest additions to the Naval air forces is a restriction on operations that cannot continue into the next generation of aircraft carriers. The Electromagnetic Aircraft Launch System (EMALS) provides solutions to all these problems .[citation needed] An electromagnetic system is more efficient, smaller, lighter, more powerful, and easier to control. Increased control means that EMALS will be able to launch both heavier and lighter aircraft than the steam catapult. Also, the use of a controlled force will reduce the stress on airframes, resulting in less maintenance and a longer lifetime for the airframe. Unfortunately the power limitations for the Nimitz class make the installation of the recently developed EMALS impossible.
Electromagnetics will also be used in the new Advanced Arresting Gear (AAG) system. The current system relies on hydraulics to slow and stop a landing aircraft. While effective, as demonstrated by more than fifty years of implementation, the AAG system offers a number of improvements. The current system is unable to capture UAVs without damaging them due to extreme stresses on the airframe. UAVs do not have the necessary mass to drive the large hydraulic piston used to trap heavier manned planes. By using electromagnetics the energy absorption is controlled by a turbo-electric engine. This makes the trap smoother and reduces shock on airframes. Even though the system will look the same from the flight deck as its predecessor, it will be more flexible, safer, and more reliable, and will require less maintenance and manning.[30]

Sensors

Another addition to the Gerald R. Ford-class is an integrated search and tracking radar system. The dual-band radar was being developed for both the Zumwalt-class guided missile destroyers and the Ford-class aircraft carriers. The island can be kept smaller by replacing six to ten radar antennas with a single six-faced radar. The DBR works by combining the X-Band AN/SPY-3 multifunction radar with the S-band volume search radar.[31] The S-band radar was later deleted from the Zumwalt class destroyers as a cost saving measure.[32] The three faces dedicated to the X-band radar are responsible for low altitude tracking and target illumination, while the other three faces dedicated to the S-band are responsible for target search and tracking regardless of weather. "Operating simultaneously over two electromagnetic frequency ranges, the DBR marks the first time this functionality has been achieved using two frequencies coordinated by a single resource manager."[19] This new system has no moving parts, therefore minimizing maintenance and manning requirements for operation.

Possible upgrades

Each new technology and design feature integrated into the Ford-class aircraft carrier improves sortie generation, manning requirements, and operational capabilities. New defense systems, such as free-electron laser directed-energy weapons, dynamic armor, and tracking systems will require more power. "Only half of the electrical power-generation capability on CVN 78 is needed to run currently planned systems, including EMALS. CVN 78 will thus have the power reserves that the Nimitz-class lacks to run lasers and dynamic armor."[33] The addition of new technologies, power systems, design layout, and better control systems results in an increased sortie rate of 25% over the Nimitz-class and a 25% reduction in manpower required to operate.[34]
Breakthrough waste management technology will be deployed on Gerald R. Ford. Co-developed with the Carderock Division of the Naval Surface Warfare Center, PyroGenesis Canada Inc., was in 2008 awarded the contract to outfit the ship with a Plasma Arc Waste Destruction System (PAWDS). This compact system will treat all combustible solid waste generated on board the ship. After having completed factory acceptance testing in Montreal, the system was scheduled to be shipped to the Huntington Ingalls shipyard in late 2011 for installation on the carrier.[35]

Construction

Construction began on components of CVN-78 in the spring of 2007,[36] and is planned to finish in 2015. It is under construction at Newport News Shipbuilding, a division of Huntington Ingalls Industries (formerly Northrop Grumman Shipbuilding) in Newport News, Virginia, the only shipyard in the United States capable of building nuclear-powered aircraft carriers. In 2005, it was estimated to cost at least $8 billion excluding the $5 billion spent on research and development (though that was not expected to be representative of the cost of future members of the class).[13] A 2009 report said that the Ford would cost $14 billion including research and development, and the actual cost of the carrier itself would be $9 billion.[37] The daily operating cost is estimated at $7 million.[38]
A total of three carriers have been authorized for construction, but if the Nimitz-class carriers and Enterprise were to be replaced on a one-for-one basis, eleven carriers would be required over the life of the program. However, the last Nimitz-class aircraft carrier is not scheduled to be decommissioned until 2058.
In a speech on 6 April 2009, then Secretary of Defense Robert Gates announced that the program would shift to a five-year building program so as to place it on a "more fiscally sustainable path". Such a measure would result in ten carriers by 2040.[39]
In 2013 a GAO report cast doubts on the delivery schedule.[40][41] As of 2013, construction costs are estimated at $12.8 billion, 22% over the 2008 budget, plus $4.7 billion in research and development costs. Because of budget difficulties, the Chief of Naval Operations, Admiral Jonathan Greenert, has warned there may be a two year delay beyond 2016 in completing the Ford.[42]

Naming

There was a movement by the USS America Carrier Veterans' Association to have CVN-78 named after America rather than after President Ford. Eventually, the amphibious assault ship LHA-6 was named America.
On 27 May 2011, the Department of Defense announced the name of CVN-79 would be USS John F. Kennedy.[43]
On 1 December 2012, Secretary of the Navy Ray Mabus announced that CVN-80 would be named USS Enterprise. The information was delivered during a prerecorded speech as part of the deactivation ceremony for the previous USS Enterprise (CVN-65). The future Enterprise (CVN-80) will be the ninth U.S. Navy ship to bear this name.[44]





























See also

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