Aircraft Carriers II (Closed to posting)

Obi Wan Russell said:

When lauching by ramp, Harrier pilots preset the nozzle control lever to 45 degrees but begin the roll with the nozzles aft for maximum acceleration. Whe they reach the ramp the nozzles are rotated to 45 degrees to provide additional lift through the transition to wingborne flight. Aircraft like the SU-33 and Mig-29K do not have rotating nozzles, instead relying on the high thrust levels of their engines at the high angle of attack produced by leaving the ramp. Raw thrust does the job, in effect.
The least best way of getting a jet off the deck of a carrier is a flat deck takeoff roll. As the article above states the Harriers need 750ft of an 800 ft deck and even then it's a struggle at full load. The next best way to get off the deck is the Ramp, because it gets you off the deck and climbing before you have reached flying speed (130+ knots), aircraft leaving the deck after 450ft at around 80 knots (SU-33s too). The best way to leave the deck is by catapult, full load of fuel and ordnance in 300ft at full flying speed (130+ knots). As a full length catapult takes up less deck space than that needed for a ramp takeoff roll and the complexity of a cat is mostly contained in those parts of the cat other than the double slotted cylinder, the costs (manufacturing and maintenance) of a cat remain broadly the same whatever the stroke length (100ft or 300ft for example) then if you are fitting a cat you may as well go the whole hog and fit a full length one. I don't see what advantage can be gained by fitting a short cat to a ramp because the aircraft's own engine can accelerate it up the ramp to the required exit speed without any catapult assistance and with much less complications. Unless you are planning to launch gliders off a ramp there is simply no need for and no advantage to a cat/ramp combination.

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A keel-laying ceremony for the first 22DDH helicopter carrier for the Japan Maritime Self-Defence Force (JMSDF) was held at IHI Marine United's (IHIMU's) Yokohama on 27 January 2012. Japan already has two helicopter carriers -- the Hyuga deployed in March 2009 and the Ise deployed in March 2011 -- but the new vessel will be larger.

The 22DDH is scheduled for deployment in 2015. It will be 248 m long and cost around US$1.04 billion. It is 30 percent bigger than the Ise and can carry 14 helicopters. The Ise measures 197 m, has a displacement of 13,500 tons and can carry 11 helicopters.

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General characteristics
Displacement: 19,500 tonnes empty
27,000 tons full load
Length: 248.0 m
Beam: 38.0 m
Speed: 30 knots
Complement: 970 (crew and troops)
Aircraft carried: up to 14 helicopters

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It is 30 percent bigger than the Ise and can carry 14 helicopters.

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TerraN_EmpirE said:

Unless of course that space is filled by something else....

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The first two years of Midway class carrier operations revealed several shortcomings which were progressively addressed with refits and modifications to maintain the ships' first-line assault carrier status. Their flight decks were reinforced to accept the landing weight of the new 45,000-lb twin-engined, jet-augmented AJ-1 Savage. At this time the process of reducing wartime armament began when four of their eighteen five-inch/54 DP guns were removed. Also begun was the gradual replacement of 40mm Bofors with twenty new three-inch/50 fast-firing semi-automatic AA guns. The test of rigorous steaming soon revealed several other deficiencies which could not be ignored. Skippers complained that the Midway's bridge area was too cramped. This was corrected during construction by extending the island structure on the Coral Sea, and retrofitting enlarged areas to the Midway and Franklin D. Roosevelt during overhaul. These changes also afforded better placement of the gun directors. Later, the three ships would be fitted with "hurricane" bows that enclosed the forward flight deck and hull.

February 1966 saw Midway decommissioned once again in order to undergo the most extensive and complex modernization ever seen on a naval vessel. This upgrade would take four years to complete, but yielded a much more capable ship and made Midway operationally equivalent to the newest conventionally powered carriers. The flight deck was increased in surface area from 2.82 acres to 4.02 acres. The addition of three new deck-edge elevators could now lift 130,000 pounds compared with 74,000 pounds of her sister ships, Franklin D. Roosevelt and Coral Sea. Two powerful new catapults on the bow, three new arresting gear engines, and one barricade were installed and rearranged to accommodate a change of 13 degrees to the angle deck. The smaller waist catapult was removed since it was ineffective in launching the now heavier aircraft. Modern electronic systems were installed, a central chilled water air conditioning system replaced hundreds of individual units, and Midway became the first ship to have the aviation fueling system completely converted from aviation gas to JP-5. Delays, caused partially by the simultaneous construction of USS Horne and modernization of USS Chicago, and unscheduled repairs to the fire damaged USS Oriskany, drove the initial modernization estimate from 87 million dollars to 202 million dollars.

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Early design discussions included debate on the aircraft carrier's mission. One view was that it could be built only for nuclear attack, against Soviet naval bases, using heavy bombers with a small hangar deck for a limited fighter escort and a small magazine for a small number of heavy nuclear weapons. Another plan was that it could be built with conventional attack capability with a large hangar deck for a large air wing and a large magazine.[5] The nuclear attack supporters won in the initial design stage, but the design was modified to carry more fighters. The flush-deck United States was designed to launch and recover the 100,000 pound (45 t)[4] aircraft required to carry early-model nuclear weapons, which weighed as much as five tons. The ship would have no island (command tower structure). It would be equipped with four aircraft elevators located at the deck edges, and four catapults, two at the bow with the outer ones at the deck edges staggered back. The carrier was designed for dual operations: landing at the rear of the ship and launching aircraft from the bow catapults, as well as launching from the four catapults simultaneously.[6] The construction cost of the new ship alone was estimated at US$189 million

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United States, a 65,000-ton attack aircraft carrier, was the Navy's first carrier of post-World War II concept and design. Intended to carry relatively large jet-propelled strategic bombers, she was laid down at Newport News, Virginia, on 18 April 1949. However, her construction was cancelled only five days later by Secretary of Defense Louis Johnson, in favor of building a large force of land-based B-36 bombers. The small amount of material already worked into the United States was subsequently broken up in her building dock.

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Jeff Head said:

The 22DDH will be far more capable than just 14 helicopters. That's the PC speak to avoind raising the rancor of pacifists and liberal pols who would want to kill it if they spoke openly about what it really is...a light aircraft carrier that will be capable of embarking the JSF and projecting power if necessary.

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