SCB-27 To handle jets, the flight deck structure was reinforced. Stronger and larger elevators, more powerful catapults, and Mk-5 arresting gear. The original four twin 5-inch/38 gun mounts were removed, clearing the flight deck of guns. The new five-inch gun battery consisted of eight weapons, two on each quarter beside the flight deck. Twin 3-inch/50 gun mounts replaced the 40 mm guns. The reconstruction eliminated the difference between "short-hull" and "long-hull" ships; all now had similar clipper bows. Island was redesigned, the boiler uptakes were rebuilt, angled aft to accommodate a single radar and communications mast atop the island. Ready rooms were moved from the gallery deck to below the armored hangar deck, with a large escalator on the starboard side amidships to move flight crews up to the flight deck. Aviation fuel capacity was increased to 300,000 US gallons (a 50% increase) and its pumping capacity enhanced to 50 US gallons. Fire fighting capabilities were enhanced through the addition of two emergency fire and splinter bulkheads to the hangar deck, a fog/foam firefighting system, improved water curtains and a cupronickel fire main. Also improved were electrical generating power, and weapons stowage and handling facilities.
SCB-27A H-8 slotted-tube hydraulic catapults, for anti-sub work only.
SCB-27C C-11 steam catapults, could then operate as CVA. Jet blast deflectors, deck cooling, fuel blending facilities, emergency recovery barrier and storage and handling for nuclear weapons. Under SCB-27C the No. 3 (after) elevator was moved to the starboard deck edge; this elevator was located further aft on the first three SCB-27C ships than it was on the ships which received it concomitantly with an angled flight deck under the SCB-125 program.
SCB 101.66 U.S.S. Midway C13-0: shuttle run 249ft; throw capacity 74,000lb@128kt; installed on Midway 1970 (SCB-101.66), Enterprise, America/JFK 3, Kitty Hawk/Constellation mid-1970s
SCB.110 C11-2: shuttle run 150ft; throw capacity 39,000lb@136kt & 70,000lb@108kt; installed on Essex class (SCB-27C), Midway & FDR waist cat 1960s (SCB-110).
SCB.110A C11-1: shuttle run 215ft; throw capacity 45,000lb@132kt & 70,000lb@108kt; installed on Oriskany. (SCB-125A), Coral Sea (all, SCB-110A), Midway & FDR bow cats (SCB-110), Forrestal/Saratoga waist, Kitty Hawk class 1960s.
SCB-125 upgrades to the Essex class of aircraft carriers conducted between 1954 and 1959. These upgrades included the addition of an angled flight deck and other enhancements aimed at improving flight operations and seakeeping.
The SCB-125 modifications included: Angled flight deck, Enclosed hurricane bow, Mirror landing system. Mark 7 arresting gear, Primary Flight Control moved to aft end of island, Air conditioning, No 1 (forward) elevator lengthened (SCB-27C ships only), No 3 (aft) elevator moved from centerline to starboard deck edge (on SCB-27A ships; had been part of SCB-27C refits).
SCB-125A addition of aluminum flight-deck cladding, Mk 7-1 arresting gear and more-powerful C 11-1 steam catapults to the standard SCB-125 modifications, Oriskany alone was referred to as a SCB-125A vessel. These changes also made Oriskany the only SCB-27A vessel to receive steam catapults.