We assume that depot maintenance periods required by a shorter month cycle would require 15, to 25, man-days per month, and therefore could perhaps be accomplished in less than the six months for which they are now scheduled.
Longer cycles could, as noted, raise several questions of feasibility. The extension of time between depot availabilities and conducting two deployments per cycle will increase maintenance demands and make it more challenging to level-load shipyards. Certain maintenance tasks must be performed at specified times to ensure that an aircraft carrier reaches its operational life of approximately 50 years. Some of these tasks could perhaps be moved, but engineering studies such as those conducted when the cycle was extended to 32 months will be required.
Furthermore, moving some of these tasks could result in depot work packages of up to , man-days, or more than twice what the public shipyards could accomplish in six months.
Longer cycles with larger work packages would also cause wide fluctuations in workload, making it difficult to efficiently manage the depot workforce and possibly leading to higher costs. Stretching work beyond the notional 6-month depot maintenance period could help level shipyard workload over time and increase the time available to accomplish required maintenance.
It would also, however, reduce the time a ship is deployed or deployable and require more time for training and certification of crews after ship maintenance.
Shorter cycles can also help level workload at the shipyards. Longer, two-deployment cycles will increase forward presence while sustaining higher levels of readiness for longer periods of time only if the workload management challenges they raise are addressed. As noted, the Navy needs to perform engineering studies to examine the impact of increased maintenance demands in two-deployment cycles.
Table 1 summarizes the advantages and disadvantages of each notional cycle mentioned above over the current month cycle. The Navy has recently adjusted personnel tempo policies to better provide carriers where and when needed. Current plans to meet demands for aircraft carrier presence include extending deployment lengths, reducing turnaround times, and, in some cases, including two deployments per cycle.
Approximately 30 percent larger than the older vessels, Izumo is feet long and displaces 27, tons. A second ship in the class, Kaga , is currently fitting out. Australia has a long tradition of operating aircraft carriers, from seaplane carriers of the s to the last full-deck Australian carrier, HMAS Melbourne , which retired in After a three-decade hiatus, the Canberra -class amphibious ships mark the return of Australian carrier aviation.
The Canberra class is designed to carry amphibious troops, and to that end, the vessels have a full-length flight deck, hangar, and elevators to move aircraft back and forth between the two. The Juan Carlos -class was built to accommodate vertical takeoff and landing fighters. However, the Australian government has downplayed the possibility of Fs operating from the decks of these twin carriers. The Cavour pictured is one of a pair of Italian carriers; the other is the Giuseppe Garabaldi.
Cavour is feet long and displaces 27, tons, while the smaller Garabaldi is feet long and displaces just 13, tons.
Both are conventionally powered, using General Electric LM gas turbine engines for propulsion. Cavour and Garabaldi are equipped with Harrier fighters and helicopters. Both carriers can send 12 helicopters or 10 Harriers into action, but only Cavour features a degree angle ski ramp to assist Harriers on takeoffs. Measuring feet long and displacing 18, tons, Dokdo is the largest warship ever built for the Republic of Korea Navy.
ROKS Dokdo 's full-length flight deck can handle up to five helicopters at once. She has a internal hangar bay just under the flight deck and two large elevators for shuttling helicopters back and forth. The ship can send up to 10 UH Blackhawk troop-carrying helicopters into action at a time.
In addition to operating as a helicopter carrier, Dokdo can act as a command ship, too. South Korea is currently expanding its naval fleet. The country announced earlier this year that it's building its first official aircraft carrier—an LPX-II-class ship that will house 15 fighter jets. The ship is feet long and displaces 33, tons fully loaded with aircraft, weapons, and fuel.
In addition to steam catapults for launching planes, she also has retractable ski jumps to give launching planes an extra boost. Her air wing consists of 12 A-4 Skyhawks, older attack jets considered obsolete but recently upgraded by Brazilian aircraft manufacturer Embraer.
She will also carry four C-1A Trader transport aircraft and an estimated 20 helicopters of various types. Despite upgrades to its propulsion systems, the ship has suffered multiple onboard fires and reportedly can't handle voyages of longer than three months. In , Brazil officially retired its sole aircraft carrier and sent it to the scrapyard.
Navy is now the only naval power in the Western Hemisphere with aircraft carriers. Named after the Spanish king who abdicated in , Juan Carlos I is an amphibious ship with a dedicated aviation role. Measuring feet long and displacing 27, tons when fully loaded, the ship can land nearly a thousand Spanish marines by air and sea. Juan Carlos I has a full-length flight deck, too, plus a pair of elevators and hangar.
It has a degree ski jump for launching Sea Harrier jump jet fighters. The ship can carry up to 30 helicopters or 10 to 12 Sea Harriers, or some mixture of both.
The study analyzed the Gulf War and the Iraq War, scenarios where these provisos were considered most likely to occur, and clearly demonstrated that high sortie generation rates are rarely needed in practice.
It would seem that whatever capabilities carrier aviation brings to the fight, these very high sortie generation rates are not the most important. Also, given the reality of the improved anti-access capabilities of powers like China, it would appear that, for the foreseeable future, such figures will be impossible to achieve in any case, since the carriers will necessarily be operating further from the coast, at least initially.
Therefore, analysts need to move beyond solely judging carriers in terms of their sortie generation rates. The U. When it comes to carrier operations, one size does not fit all. Navy, most likely because of its flexibility and the fact that it can accomplish a multitude of missions.
However, U. In other words, they are over-specified for the tasks at hand. This begs the question: How much more flexibility would naval planners have if they had a range of carrier capabilities to use?
Interestingly, the three navies who have made significant use of carrier aviation during the last century the American, British, and Japanese navies have found that a fleet composed solely of large fleet carriers was out of their reach financially, no matter how much they may have wanted them.
As a result, all three nations resorted to a combination of fleet carriers augmented by a greater number of less-capable ships: the numerous light carriers and escort carriers of World War II fame. In the case of the United Kingdom and the United States, this was resoundingly successful. In addition, the limited capabilities of the lesser ships actually enhanced the availability of the fleet carriers in their prime mission areas. Both London and Washington tried to reserve their scarce fleet carriers for the more important sea-control missions while using the less-capable light carriers for specialist missions such as anti-submarine warfare, convoy protection, and amphibious landing support.
The idea was that the large, fast fleet carriers would first gain wide-area sea control so as to facilitate the access of the supporting forces. Lighter, less-capable carriers would then take over the local sea-control requirements to allow amphibious operations or the protection of the sea train. This, in turn, would free up the fast carriers to continue with their wide-area operations elsewhere.
In effect, the possession of a range of carrier capabilities allows the fleet as a whole to achieve much more. As the expression goes, necessity is the mother of invention. In theory, there is absolutely no reason to doubt that such a useful symbiosis is equally achievable today.
For example, the same RAND study mentioned earlier looked at four modern carrier options aimed at saving money. Of these options, the first was dismissed as not offering sufficient savings for the loss of capability incurred. A total of ten Ford-class carriers are planned with construction continuing to The keel was laid in November The CVN 78 aircraft carrier was installed with four 30t bronze propellers in October Both the launch and first voyage of the ship took place in November Newport News won a contract to support further repair work on the lead ship.
Northrop Grumman was awarded a planning and design contract for the second carrier, CVN 79, in November The keel for CVN 79 was laid in August The first steel was cut for the CVN 80 aircraft carrier in August The company expects to deliver the carriers in and respectively.
With a displacement of approximately ,t, the Gerald R Ford class will be larger than its predecessor, the Nimitz-class , but will have between and fewer crew members. The Ford-class ships will have 23 new or upgraded systems compared to the Nimitz-class carriers. The manpower reduction was a key performance parameter added to the original four outlined in in the operational requirements document for the CVN 21 programme.
Another key performance requirement is interoperability.
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