Given one deployment per cycle, this has reduced the time a carrier is actually deployed but increased the amount of time it is able to surge. The Navy asked RAND to assess how differing cycles would affect the amount of time a ship is able to deploy or be deployed. Given a fixed number of months for maintenance, deployments, and time between deployments consistent with personnel quality-of-life goals , Navy planners face a three-sided trade-off in setting ship schedules.
They must balance goals of:. This is a zero-sum trade-off in which improving the ability to meet one goal can adversely affect the ability to meet the others see Figure 1.
Under the current month, one-deployment cycle, for example, in which both the deployment and maintenance periods typically last six months, a carrier is deployed 19 percent of the time, able to surge within 30 days 46 percent of the time and within days an additional 11 percent of the time, and in depot maintenance 24 percent of the time. A shorter, month cycle would see a carrier deployed 31 percent of the time, able to surge within 30 days 15 percent of the time and within days 18 percent of the time, and in depot maintenance 36 percent of the time.
A longer, month cycle featuring two 6-month deployments would see a carrier deployed 29 percent of the time, able to surge within 30 days 44 percent of the time and within days 9 percent of the time, and in maintenance 18 percent of the time.
It is not clear, however, whether required depot maintenance can be completed in one 6-month period every three and a half years. RAND researchers also assessed the technical feasibility of maintenance cycles of varying lengths. Prior to the current month cycle, Nimitz-class carriers operated on cycles of months. This suggests that shorter cycles, by offering more-frequent opportunities to accomplish depot work, are technically feasible.
Shorter cycles may also help in level-loading work at the shipyards, with more-frequent depot visits resulting in smaller work packages. Currently, the two public shipyards that perform depot-level maintenance for carriers can efficiently execute about 30, man-days per month. 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. The six turbo alternators and six diesel alternators aboard the vessel generate a total power of 18MW.
It is also the only nuclear-powered carrier in service outside of the US Navy. The French aircraft carrier underwent a six-month refit, which was concluded at Toulon naval base in July Its power plant comprises of two K15 pressurised water reactors and provides a speed of 27kt.
It is a Clemenceau-Class aircraft carrier currently operated by the Brazilian Navy. Its flight deck can accommodate 39 aircraft including fighters, fixed-wing aircraft and helicopters. The propulsion system of the vessel provides a maximum speed of 32kt.
The Cavour features a The vessel can complement 1, crew, including troops. The armament includes short range defence systems, guns and decoy launchers defending against a variety of threats.
It is also the oldest carrier, serving as the flagship of the Indian Navy. It complements a crew of 1,, including 43 officers. The Bofors AA guns and Barak surface-to-air missile SAM launchers mounted on the Viraat aircraft carrier protect the ship from aerial and surface attacks. The steam turbine propulsion system provides a maximum speed of 28kt. Join Our Newsletter Get important industry news and analysis sent to your inbox — sign up to our e-Newsletter here.
News Analysis Features Comment Projects. Join Our Newsletter - Get important industry news and analysis sent to your inbox — sign up to our e-Newsletter here. After Desert Storm, the Navy quickly recognized that it was time for new thinking. The chief of naval operations, Adm. Frank B. Kelso II, put Navy analysts to work blending the lessons of Desert Storm with an even older Navy tradition of expeditionary warfare.
The Navy immediately began procurement of precision guided weapons. The deck mix had changed, too. Along the way, forward presence requirements replaced warfighting requirements as the major factor in the sizing of the carrier force. Donald L. Maintaining two carriers on station at any hub-for example, during a crisis with Iraq-strained the entire fleet, disrupting everything from deployment cycles to ammunition allotments. By the mids, carriers had the starring role in a new littoral strategy.
In early , the chief of naval operations, Adm. Jay L. Carrier capabilities had indeed improved, and carriers undeniably have been busy meeting on-station requirements in the Med and Gulf and showing force in events like the Taiwan Strait crisis of Yet claims of sustainable carrier firepower and high sortie rates were unproven. Several mids operations in the Balkans provided real-world tests of carrier striking power in a littoral environment.
Six carrier battle groups eventually took a turn on station in the Adriatic from early through December Bosnian airspace was only about miles from the typical carrier launch site.
Even with a benign environment from which to launch, the Navy generated only 8, sorties, about 10 percent of the NATO total. The total was exceeded by both the French air force 12, sorties and the Royal Air Force 10, sorties during the same period. Over two weeks in August and September , NATO aircraft conducted a campaign to defend safe areas and degrade Bosnian Serb military effectiveness by striking targets around Sarajevo and throughout Serb-controlled territory in northwest Bosnia.
US naval aviators now had precision guided weapons, a coordination cell in the Combined Air Operations Center, and much improved abilities to receive the CAOC daily air tasking message. Land-based USAF aircraft flew feet dry sorties and support sorties.
Still, land-based forces surpassed naval contributions in delivery of PGMs. US forces expended PGMs, scoring hits. Of this number USAF aircraft accounted for hits Thus, strikes launched from sea tallied about a quarter of the hits with PGMs. Deliberate Force comprised 11 days of actual operations. During this period, Navy sea-based strikers flew sorties, meaning that the output of sea-based aviation averaged 53 sorties per day. During that same period, 46 land-based USAF aircraft flew total strike sorties.
The Air Force contribution works out to an average of 70 sorties per day or a daily per aircraft sortie rate of 1. The clear expectation was that the carrier would make a good showing. Said then-Rear Adm. Dennis V. Over 98 hours, carrier Nimitz and its air wing, CVW-9, generated fixed-wing sorties. As the Navy told it, this was not just an exercise but also a valid indicator of real-world capabilities.
Nathman, commander of the Nimitz battle group, claimed as much to a reporter on Oct. Angelyn L. When operations began, the aircrews were ready, the aircraft were groomed, and the ordnance was staged, they pointed out. This augmentation of the aircrews was essential to generation of almost strike sorties per day.
Augmentees also formed a strike planning cell, whose work helped reduce the amount of time each aircrew had to spend in mission preparation.
Nimitz also took on a full load of ordnance and replenished its aviation fuel stores while under way. S-3s did duty as recovery tankers—topping off jets as they returned to the carrier for landing.
Placed in context, however, SURGEX results indicate a capability that would fit only a narrow band of potential real-world joint operations.
The problems boil down to time and range if a carrier operates by itself. The high sortie rate demonstrated in SURGEX relied on nonstandard conditions such as access to extra pilots and short sortie durations that would be hard to repeat under contingency conditions.
Ironically, the short sortie cycles that SURGEX worked so hard to achieve would pose a major challenge in time of war. One-hour cycles pushed the deck crews too hard. But short cycles would limit the combat radius of carrier aircraft, especially those in a heavy bomb-dropping or close air support configuration. With such time requirements, targets more than miles from the carrier would prove to be out of reach. The short sorties reflected a blue-water, ocean-control legacy, not a realistic littoral scenario.
Some critical targets may be that close to a coastline, but the majority probably would not. Carrier strike aircraft may be free to operate from a deck in international waters, but they depend on land-based support to reach maximum combat effectiveness.
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