In January 2007, the US Navy announced that the new class would be called the Gerald R Ford Class.
Gerald R. Ford class (or Ford class, previously known as CVN-21 class) is a class of supercarriers currently being built to replace some of the United States Navy's existing Nimitz-class carriers beginning in 2016 when CVN-78 is delivered to the U.S. Navy. 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 operating costs, including reduced crew requirement. The first ship of the class, USS Gerald R. Ford, has hull number CVN-78.
USS Gerald R Ford (CVN 78) and USS John F Kennedy (CVN 79)
The first two ships, USS Gerald R Ford (CVN 78) and USS John F Kennedy (CVN 79), will be commissioned in 2016 and 2020 respectively, and further ships of the class will enter service at intervals of five years. A total of ten Ford-class carriers are planned with construction continuing to 2058.
The CVN 78 will replace USS Enterprise (CVN 65), which entered service in 1961 and will approach the end of its operational life by 2015. The total acquisition cost of the CVN 21 is expected to be $13.7bn.
The US Department of Defense awarded Northrop Grumman Newport News in Virginia a $107.6m contract in July 2003, a $1.39bn contract in May 2004 and $559m to prepare for the carrier construction and continue the design programme on the ship's propulsion system.
The CVN 78's first steel was cut in August 2005. A $5.1bn contract for the detailed design and construction was awarded to Newport News in September 2008. The keel was laid in November 2009.
The CVN 78 aircraft carrier was installed with four 30t bronze propellers in October 2013. Both the launch and first voyage of the ship took place in November 2013. Anchor testing aboard the carrier was completed in June 2014, while the US Navy conducted EMALS testing on CVN 78 in May 2015.
Northrop Grumman was awarded a planning and design contract for the second carrier, CVN 79, in November 2006. In May 2011, the US Navy announced that the carrier will be called John F Kennedy.
Construction of the USS John F Kennedy (CVN 79) began in February 2011 and is expected for completion in 2020.
Newport News was awarded a $407m contract extension for the preparation work on the CVN 79 ship in March 2013 and a $1.29bn contract extension in March 2014. It further received a $3.35bn contract for the ship's detailed design and construction in June 2015.
CVN 21 future aircraft carrier design
The Gerald R Ford class carriers will have the same displacement, about 100,000t, as its predecessor, the Nimitz-class George HW Bush (CVN 77), but will have between 500 and 900 fewer crew members.
The manpower reduction was a key performance parameter added to the original four outlined in 2000 in the operational requirements document for the CVN 21 programme. It is estimated that the new carrier technologies will lead to a 30% reduction in maintenance requirements and a further crew workload reduction will be achieved through higher levels of automation.
The other main differences in operational performance compared with the Nimitz-class are increased sortie rates at 160 sorties a day (compared with 140 a day), a weight and stability allowance over the 50-year operational service life of the ship, and increased (by approximately 150%) electrical power generation and distribution to sustain the ship's advanced technology systems. Another key performance requirement is interoperability.
CVN 21 aircraft carrier hull
Since the 1960s, all US Navy aircraft carriers have been built at Northrop Grumman Newport News. Northrop has extended its design and shipbuilding facilities with a new heavy plate workshop and burners, a new 5,000t thick plate press, covered assembly facilities and a new 1,050t-capacity crane.
Northrop is using a suite of computer-aided design (CAD) tools for the CVN 21 programme, including a CATIA software suite for simulation of the production processes and a CAVE virtual environment package.
The hull design is similar to that of the current Nimitz Class carriers and with the same number of decks. The island is smaller and moved further towards the aft of the ship.
The island has a composite mast with planar array radars, a volume search radar operating at S band and a multifunction radar at X band, and also carries the stern-facing joint precision approach and landing system (JPALS), which is based on local area differential global positioning system (GPS), rather than radar.
The aircraft carrier traditionally carries the flag officer and 70 staff of the carrier battle group. The flag bridge, which was previously accommodated in the carrier's island, was relocated to a lower deck in order to minimise the size of the island.
The ship's internal configuration and flight deck designs have significantly changed. The lower decks incorporate a flexible rapidly reconfigurable layout allowing different layouts and installation of new equipment in command, planning and administration areas.
The requirement to build in a weight and stability allowance will accommodate the added weight of new systems that will be installed over the 50-year operational life of the ship. The removal of one aircraft elevator unit and reducing the number of hangar bays from three to two have contributed to a weight reduction of the CVN 21.
Power generation
The new reactor for the CVN 21 class overcomes many of the shortfalls of the Nimitz-class reactor and is an enabler for many of the other technologies and improvements planned for the new class. Two Bechtel A1B nuclear reactors will be installed on each Ford-class carrier, with each A1B reactor capable of producing 300 MW of electricity, compared to the 100 MW of each Nimitz-class reactor.
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." Increasing the capability of the U.S. Navy to improve the technological level of the carrier fleet required a larger capacity power system.
Compared to the Nimitz-class reactor, the CVN 21 reactor will have approximately 50 percent fewer valves, piping, major pumps, condensers, and generators. The steam-generating system will use fewer than 200 valves and only 8 pipe sizes. These improvements lead to simpler construction, reduced maintenance, and lower manpower requirements as well as to a more compact system that requires less space in the ship. 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.
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.
Electromagnetic Aircraft Launch System
Main article: Electromagnetic Aircraft Launch System
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.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." The steam system is massive, inefficient (4–6%), and hard to control.
Control problems with steam-powered aircraft launch systems on Nimitz-class carriers result in minimum and maximum weight limits. The minimum weight limit on steam-powered catapults is above the weight of all UAVs which represents a substantial shortfall in capability (an inability to launch the latest additions to the Naval air forces is a restriction on naval operations that cannot continue into the next generation of aircraft carriers).
The Electromagnetic Aircraft Launch System (EMALS) 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. The power limitations for the Nimitz class make the installation of the recently developed EMALS impossible.
In June 2014, the Navy completed EMALS prototype testing of 450 manned aircraft launches involving every fixed-wing carrier-borne aircraft type in the USN inventory at Joint Base McGuire-Dix-Lakehurst during two Aircraft Compatibility Testing (ACT) campaigns. ACT Phase 1 concluded in late 2011 following 134 launches (aircraft types comprising the F/A-18E Super Hornet, T-45C Goshawk, C-2A Greyhound, E-2D Advanced Hawkeye, and F-35C Lightning II). On completion of ACT 1, the EMALS demonstrator was reconfigured to be more representative of the actual ship configuration on board Ford, which will use four catapults sharing several energy storage and power conversion subsystems.
ACT Phase 2 began on 25 June 2013 and concluded on 6 April 2014 after a further 310 launches (including launches of the EA-18G Growler and F/A-18C Hornet, as well as another round of testing with aircraft types previously launched during Phase 1). In Phase 2 various carrier situations were simulated, including off-centre launches and planned system faults, to demonstrate that aircraft could meet end-speed and validate launch-critical reliability.EMALS was tested in June 2015.
Advanced Arresting Gear landing system
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 the hydraulic system is 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, safe, and reliable, and will require less maintenance and manning.
Sensors and self-defense systems
Another addition to the Gerald R. Ford class is an integrated Active electronically scanned array search and tracking radar system. The dual-band radar (DBR) was being developed for both the Zumwalt-class guided missile destroyers and the Ford-class aircraft carriers by Raytheon. 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 (VSR) emitters, distributed into three phased arrays. The S-band radar was later deleted from the Zumwalt class destroyers as a cost saving measure.
The three faces dedicated to the X-band radar are responsible for low altitude tracking and radar 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."
This new system has no moving parts, therefore minimizing maintenance and manning requirements for operation. The carrier will be armed with the Raytheon evolved Sea Sparrow missile (ESSM), which defends against high-speed, highly maneuverable anti-ship missiles. The close-in weapon system is the rolling airframe missile (RAM) from Raytheon and Ramsys GmbH.
The AN/SPY-3 consists of three active arrays and the Receiver/Exciter (REX) cabinets abovedecks and the Signal and Data Processor (SDP) subsystem below-decks. The VSR has a similar architecture, with the beamforming and narrowband down-conversion functionality occurring in two additional cabinets per array. A central controller (the resource manager) resides in the Data Processor (DP). The DBR is the first radar system that uses a central controller and two active-array radars operating at different frequencies. The DBR gets its power from the Common Array Power System (CAPS), which comprises Power Conversion Units (PCUs) and Power Distribution Units (PDUs). The DBR is cooled via a closed-loop cooling system called the Common Array Cooling System (CACS).
The REX consists of a digital and an analog portion. The digital portion of the REX provides system-level timing and control. The analog portion contains the exciter and the receiver. The exciter is a low-amplitude and phase noise system that uses direct frequency synthesis. The radar’s noise characteristics support the high clutter cancellation requirements required in the broad range of maritime operating environments that DBR will likely encounter. The direct frequency synthesis allows a wide range of pulse repetition frequencies, pulse widths, and modulation schemes to be created.
The receiver has high dynamic range to support high clutter levels caused by close returns from range-ambiguous Doppler effect waveforms. The receiver has both narrowband and wideband channels, as well as multichannel capabilities to support monopulse radar processing and sidelobe blanking. The receiver generates digital data and sends the data to the signal processors.
The DBR uses IBM commercial off-the-shelf (COTS) supercomputers to provide control and signal processing. DBR is the first radar system to use COTS systems to perform the signal processing. Using COTS systems reduces development costs and increases system reliability and maintainability.
The high-performance COTS servers perform signal analysis using radar and digital signal processing techniques, including channel equalization, clutter filtering, Doppler processing, impulse editing, and implementation of a variety of advanced electronic protect algorithms. The IBM supercomputers are installed in cabinets that provide shock and vibration isolation. The DP contains the resource manager, the tracker, and the command and control processor, which processes commands from the combat system.
The DBR utilizes a multitier, dual-band tracker, which consists of a local X band tracker, a local S band tracker, and a central tracker. The central tracker merges the local tracker data together and directs the individual-band trackers’ updates. The X band tracker is optimized for low latency to support its mission of providing defense against fast, low-flying missiles, while the VSR tracker is optimized for throughput due to the large-volume search area coverage requirements.
The combat system develops doctrine-based response recommendations based on the current tactical situation and sends the recommendations to the DBR. The combat system also has control of which modes the radar will perform. Unlike previous-generation radars, the DBR does not require an operator and has no manned display consoles. The system uses information about the current environment and doctrine from the combat system to make automated decisions, not only reducing reaction times, but also reducing the risks associated with human error. The only human interaction is for maintenance and repair activities.
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." 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.
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.
The Navy is actively developing a weapon system called the free-electron laser (FEL) to address the cruise missile threat and the swarm-boat threat against Ford-class carriers. An FEL uses an electron gun to generate a stream of electrons. The electrons are then sent into a linear particle accelerator to accelerate them to near light speeds. The accelerated electrons are then sent into a device, known informally as a wiggler, that exposes the electrons to a transverse magnetic field, which causes the electrons to “wiggle” from side to side and release some of their energy in the form of light (photons). The photons are then bounced between mirrors and emitted as a coherent beam of laser light. To increase the efficiency of the system, some of the electrons are then cycled back to the front of the particle accelerator via an energy recovery loop. The cost to fire one round from an FEL is about $1 and consumes about 10 MW of electricity.
3D computer-aided design
Newport News Shipbuilding used a full-scale three-dimensional product model developed in Dassault Systèmes CATIA V5 release 8 (which includes special features useful to shipbuilders) to design and plan the construction of the Ford class of aircraft carriers. This enables engineers and designers to test visual integration in design, engineering, planning and construction of components and subsystems. CVN-78 is the first aircraft carrier to be designed in a full-scale 3D product model. This modeling enabled the rooms within the ship to be modular, so that future upgrades can be implemented by designers simply by swapping a box in and locking it down.
This method of designing workflow also resulted in improvements to weapon handling procedures and an increase in potential sorties-per-day. Weapons-handling paths on Nimitz-class ships were designed for the potential nuclear missions of the Cold War. The current flow of weapons from storage areas in the interior of the Nimitz-class ship to loading on aircraft involves several horizontal and vertical movements to various staging and build-up locations within the ship. These movements around the ship are time-consuming and manpower-intensive and typically involve sailors manually moving weapons loaded on carts. Also, the current locations of some of the Nimitz-class weapons elevators conflict with the flow of aircraft on the flight deck, slowing down the generation of sorties or making some elevators unusable during flight operations.
The CVN 21 class was designed to have better weapons movement paths, largely eliminating horizontal movements within the ship. Current plans call for advanced weapons elevators to move from storage areas to dedicated weapons-handling areas. Sailors would use motorized carts to move the weapons from storage to the elevators at different levels of the weapons magazines. Linear motors are being considered for the advanced weapons elevators. The elevators will also be relocated such that they will not impede aircraft operations on the flight deck. The redesign of the weapons movement paths and the location of the weapons elevators on the flight deck will reduce manpower and contribute to a much higher sortie generation rate.
Aircraft weapons loading
The flow of weapons to the aircraft stops on the flight deck was upgraded to accommodate the higher sortie rates. The ship carries stores of missiles and cannon rounds for fighter aircraft, bombs and air-to-surface missiles for strike aircraft, and torpedoes and depth charges for anti-submarine warfare aircraft.
Weapons elevators take the weapons systems from the magazines to the weapons handling and weapons assembly areas on the 02-level deck (below the flight deck) and express weapons elevators are installed between the handling and assembly areas and the flight deck. The two companies selected by Northrop Grumman to generate designs for the advanced weapons elevator are the Federal Equipment Company and Oldenburg Lakeshore Inc.
The deployment of all-up-rounds, which are larger, rather than traditional weapons requiring assembly will require double-height magazines and store rooms and will also impact on the level of need for weapons assembly facilities.
The US Navy outlined a requirement for a minimum 150% increase in the power-generation capacity for the CVN 21 carrier compared with the Nimitz Class carriers. The increased power capacity is needed for the four electro-magnetic aircraft launchers and for future systems such as directed energy weapons that might be feasible during the carrier's 50-year lifespan.
Planned aircraft complement
The Ford class is designed to accommodate the new Joint Strike Fighter carrier variant aircraft (F-35C), but aircraft development and testing delays have affected integration activities on CVN-78. These integration activities include testing the F-35C with CVN-78’s EMALS and advanced arresting gear system and testing the ship’s storage capabilities for the F-35C’s lithium-ion batteries (which provide start-up and back-up power), tires, and wheels. As a result of F-35C developmental delays, the Navy will not field the aircraft until at least 2017—one year after CVN-78 delivery. As a result, the Navy has deferred critical F-35C integration activities, which introduces risk of system incompatibilities and costly retrofits to the ship after it is delivered to the Navy.
Crew accommodations
A typical berthing on Ford-class aircraft carriers of three racks per section
Systems that reduce crew workload have allowed the ship’s company on Ford-class carriers to total only 2,600 sailors, about 600 fewer than a Nimitz-class flattop. The massive, 180-man berthing areas on the Nimitz class are replaced by 40 racks per berthing on Ford-class carriers. The smaller berthings are quieter and the layout requires less foot traffic through other spaces.
The racks are typically stacked three high, with one locker per person and extra lockers for those without storage space under their rack. The berthings, however, do not feature “sit-up” racks with more headroom (each rack can only accommodate a sailor lying down). Each berthing has an associated head, including showers, vacuum-powered septic system toilets (no urinals since the berthings are built gender-neutral), and sinks to reduce travel and traffic to access those facilities. Wifi-enabled lounges are located across the passageway in separate spaces from the berthing’s racks.
First-of-class type design changes
As construction of CVN-78 progresses, the shipbuilder is discovering first-of-class type design changes, which it will use to update the model prior to the follow-on ship construction. To date, several of these design changes have related to EMALS configuration changes, which have required electrical, wiring, and other changes within the ship. Although the Navy reports that these EMALS-related changes are nearing completion, it anticipates additional design changes stemming from remaining advanced arresting gear development and testing. In total, over 1,200 anticipated design changes remain to be completed (out of nearly 19,000 planned changes). According to the Navy, many of these 19,000 changes were programmed into the construction schedule early on—a result of the government’s decision at contract award to introduce improvements during construction to the ship’s warfare systems, which are heavily dependent on evolving commercial technologies.
Sensors
Raytheon was contracted in October 2008 to supply a version of the dual-band radar (DBR) developed for the Zumwalt Class destroyer for installation on the Gerald R Ford. DBR combines X-band and S-band phased arrays.
Propulsion
Northrop Grumman is developing the advanced nuclear propulsion system and a zonal electrical power distribution system for the CVN 21.
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.
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.
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