Flight deck

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Eugene Ely's first landing, on the armored cruiser USS Pennsylvania

Early flight decks[edit]



Full length decks[edit]

Flight deck resurfacing aboard USS Peleliu (LHA-5)




Armored decks[edit]

Main article: Armoured flight deck

When aircraft carriers supplanted battleships as the primary fleet capital ship, there were two schools of thought on the question of armor protection being included into the flight deck. The USN initially favored unarmored flight decks because they maximized aircraft carrier hangar and flight deck size, which in turn maximized aircraft capacity in the hangar, and on the flight deck, in the form of a permanent "deck park" for a large proportion of the aircraft carried.[2][3] In 1936 the Royal Navy developed the armored flight deck aircraft carrier which also enclosed the hangar sides and ends with armor. The addition of armor to the flight deck offered aircraft below some protection against aerial bombs while the armored hangar sides and ends helped to minimize damage and casualties from explosions or fires within or outside the hangar.[4] The addition of armor to the hangar forced a reduction in top-weight, so the hangar height was reduced, and this restricted the types of aircraft that these ships could carry, although the Royal Navy's armored carriers did carry spare aircraft in the hangar overheads.[5] The armor also reduced the length of the flight deck, reducing the maximum aircraft capacity of the armored flight deck aircraft carrier. Additionally, Royal Navy aircraft carriers did not use a permanent deck park until approximately 1943; before then the aircraft capacity of RN aircraft carriers was limited to their hangar capacity. The 23,000 ton British Illustrious-class had a hangar capacity for 36 Swordfish sized aircraft and a single 458 ft x 62 ft x 16 ft ( 140m x 19m x 4.8m) hangar, but carried up to 57 [6] aircraft with a permanent deck park while the 23,400 ton Implacable class featured increased hangar capacity with a 458 ft x 62 ft x 14 ft ( 140m x 19m x 4.3m) upper hangar and the addition of a 208 ft by 62 ft by 14 ft (63m x 19m x 4.3m) lower hangar, forward of the after elevator, which had a total capacity of 52 Swordfish sized aircraft or a mix of 48 late war aircraft in the hangar plus 24 aircraft in a permanent deck park[7],[7] but carried up to 81 aircraft with a deck park.[8] The 27,500 ton USN Essex class had a 654 ft x 70 ft x 17.5 ft (198m x 21m x 5.3m) hangar that was designed to handle a mix of 72 prewar USN aircraft.[9] but carried up to 104 late war aircraft using both the hangar and a permanent deck park.[10][11] The experience of World War II caused the USN to change their design policy in favor of armored flight decks: "The main armor carried on Enterprise is the heavy armored flight deck. This was to prove a significant factor in the catastrophic fire and explosions that occurred on Enterprise's flight deck in 1969. The US Navy learned its lesson the hard way during World War II when all its carriers had only armored hangar decks. All attack carriers built since the Midway class have had armored flight decks."[12]

Landing on flight decks[edit]

See also: Arresting gear




Modern innovations[edit]

Angled flight deck[edit]

Overhead view of HMS Ark Royal showing the angled flight deck

The angled flight deck was invented by Royal Navy Captain (later Rear Admiral) Dennis Cambell, as an outgrowth of design study initially begun in the winter of 1944-45 when a committee of senior Royal Navy officers decided that the future of naval aviation was in jets, whose higher speeds required that the carriers be modified to "fit" the needs of jets.[13][14][15] With this type of deck, (also referred to as a "skewed deck" or "canted deck" or the "angle"), the aft part of the deck is widened and a separate runway is positioned at an angle from the centreline.[16] The angled flight deck was designed with the higher landing speeds of jet aircraft in mind, which would have required the entire length of a centreline flight deck to stop.[16] The design also allowed for concurrent launch and recovery operations, and allowed aircraft failing to connect with the arrestor cables to abort the landing, accelerate, and relaunch (or "bolter") without risk to other parked or launching aircraft.[16]

Animated representation of how the angled flight deck allows for simultaneous launch and recovery operations without risk of aircraft colliding on deck. Nimitz class carrier USS Dwight D. Eisenhower illustrating how increasing the offset angle of a carrier's recovery area allows the use of two catapults during launch and recovery operations.


The angled flight deck was first tested on HMS Triumph by painting angled deck markings onto the centerline of the flight deck for touch and go landings.[16] This was also tested on the USS Midway the same year.[17][18] Despite the new markings, in both cases the arresting gear and barriers were still aligned with the centerline of the original deck. From September to December 1952, the USS Antietam had a rudimentary sponson installed for true angled deck tests, allowing for full arrested landings, which proved during trials to be superior.[19] In 1953, Antietam trained with both U.S. and British naval units, proving the worth of the angle deck concept.[20] HMS Centaur was modified with overhanging angled flight deck in 1954.[16] The U.S. Navy installed the decks as part of the SCB-125 upgrade for the Essex-class and SCB-110/110A for the Midway-class. In February 1955, HMS Ark Royal became the first carrier to be constructed and launched with an angled deck, rather than having one retrofitted. This was followed in the same year by the lead ships of the British Majestic-class (HMAS Melbourne) and the American Forrestal-class (USS Forrestal).[16]

Ski-jump ramp[edit]

Ski-jump flight deck of the Royal Navy's Invincible class, HMS Ark Royal
Expansive Flight Deck of INS Vikramaditya at night showing the ski-jump ramp used for STOBAR configuration
A Sea Harrier takes off from the flight deck of Indian Navy aircraft carrier INS Viraat (R22) during Malabar 2007

Another British innovation is the ski-jump ramp, which came about as a means of improving take off for the VSTOL BAE Sea Harrier "jump-jet" on the small Invincible class aircraft carriers. From an idea by Lt Cdr D.R. Taylor, RN, in 1973,[21] initial testing was carried out at the RAE Bedford. They are most common on aircraft carriers supporting STOVL aircraft such as the Harrier, but the Russians also used them with conventional MiG-29s and Su-33s.

The ski jump is a ramp which is curved upwards at its forward end. For STOVL aircraft the aircraft starts by making a conventional rolling takeoff with the jet exhausts set to provide maximum forward thrust. As the plane nears the end of the ramp (the ski jump portion) the jet exhausts are rotated to provide upward lift as well as forward thrust. Rolling over the ski ramp launches the plane both upwards and forwards. As the plane leaves the ski jump ramp it continues to accelerate horizontally until the wings can provide the needed lift.

For conventional aircraft such as the MiG-29 the aircraft just rolls down the runway in the obvious manner. Again, rolling over the ski ramp launches the plane both upwards and forwards.

Such takeoffs allow a larger takeoff weight than an unassisted horizontal launch because the ski jump ramp provides a vertical impetus when most needed, right at takeoff at the slowest takeoff speed; however, ski-jump launches cannot match the payloads made possible by high-speed catapult launches.

These takeoffs use less runway than a takeoff over a flat surface because the plane takes off at a lower speed, using both the ski jump ramp's vertical impetus and the deflected jet engines to generate lift.

Ski jump ramp takeoffs are considered safer than takeoffs over a flat top carrier. When a Harrier launches from an American LHA (Landing Helicopter Assault) it might finish its takeoff roll and begin flight at 60 ft (18 m) above the water. It might not have a positive rate of climb, especially if the ship had pitched nose down during the takeoff roll. Using a ski jump ramp the plane will certainly launch with a positive rate of climb and its momentum will carry it to 150 to 200 ft (46 to 61 m) above the water.[22]

For example, an AV-8B Harrier with a gross weight of 29,000 lb (13,000 kg) on a 59 °F (15 °C) day and a 35 kn (40 mph; 65 km/h) wind over the deck would require 400 ft (120 m) to takeoff using a 12° ski jump ramp designed as on the Principe de Asturias, but 750 ft (230 m) without the ski jump ramp.[22]

For a MiG-29 launching over the ski jump ramp on the Tbilisi, takeoff speed is reduced from about 140 kn (160 mph; 260 km/h) to about 70 kn (81 mph; 130 km/h) (depending on many factors such a gross weight).[23]

Carriers using STOVL aircraft and a ski jump ramp do not need catapults nor arresting gear.

With the exception of the United States, France and Brazil, every navy in the world that operates STOVL naval aircraft uses ski jump ramps.[22]

Flexible decks[edit]





See also[edit]


  1. ^ "Flight From the Hibernia". The Times (London) (39895): 8 col.3. 10 May 1912. 
  2. ^ Hone, Friedman, Mandeles, British and American Carrier Development, 1919-1941, p125.
  4. ^ Eadon, Stuart, editor, Kamikaze, The Story of the British Pacific Fleet, Worcester 1991, ISBN 1-872017-23-1, p.338-339: In nine kamikaze strikes "...The Fleet Air Arm suffered...44 personnel killed...By contrast Bunker Hill lost 387 dead in the Kamikaze attack on 11th of May 1945."
  5. ^ Roberts, British Warships of the Second World War, p62.
  6. ^ Brown, David, Warship Profile 11, HMS Illustrious Aircraft Carrier 1939–1956, Operational History, p257. 42 F4U Corsairs and 15 Fairey Barracudas.
  7. ^ Roberts, British Warships of the Second World War, p.61.
  8. ^ OOB Carrier raids on the Japanese home islands. 48 Seafires, 21 Avengers and 12 Fireflies.
  9. ^ Roberts, John, The Aircraft Carrier Intrepid. London: Conway Maritime Press, 1982.
  10. ^ OOB Carrier raids on the Japanese home islands. USS Bennington: 37 Hellcats, 37 Corsairs, 15 Helldivers and 15 Avengers.
  11. ^ Francillion, Rene, US Navy Carrier airgroups Pacific, 1941-1945, London, Osprey Press 1978.ISBN 085045 2910
  12. ^ Cracknell, W.H, Cmdr USN, Warship Profile 15, USS Enterprise (CVAN 65) Nuclear Attack Carrier, p56.
  13. ^ Denniscambell.org.uk
  14. ^ "History of the Fleet Air Arm". 
  15. ^ Innovation in Carrier Aviation, Newport Paper 37 (Naval War College Press: 2011), by Thomas C. Hone, Norman Friedman, and Mark D. Mandeles; abridged findings published as "The Development of the Angled-Deck Aircraft Carrier" in the Spring 2011 issue of Naval War College Review (Vol.64, No. 2) pp.63-78.
  17. ^ U.S. aircraft carriers By Norman Friedman, A. D. Baker, III. 
  18. ^ "unknown". 
  19. ^ "U.S. aircraft carriers: an illustrated design history". googlebooks. 
  20. ^ "Awards" (PDF). 
  21. ^ http://www.flightglobal.com/pdfarchive/view/1976/1976%20-%202837.html
  22. ^ a b c History.navy.mil
  23. ^ Mikoyan MiG-29, Yefim Gordon, p 84
  24. ^ Thunder and Lightnings - Scimitar 21 May 2007
  25. ^ de Havilland Sea Vampire belly landing on a rubber deck
  26. ^ Author: Greg Goebel. "The full story of the Harrier "Jump-Jet" Part Four - the "Second Generation" Harriers - The BAe / MDD AV-8B Harrier II, GR.5, GR.7, GR.9 & T.10 Harriers". Wingweb.co.uk. Retrieved 2013-11-10.