Staff Writer (Updated: 4/21/2015):
Origins of the A-7 reside back in a 1962 USN initiative which produced the VAX ("Heavier-than-Air, Attack, Experimental") program seeking a follow-up design to the aging A-4 platform. A budget-conscious approach was selected in which an existing airframe was to serve as the basis for the new aircraft. This would also expedite development and ultimate serial production of the strike fighter. Key industry powerhouses such as Douglas, Grumman, North American, and Vought (part of Ling-Temco-Vought = LTV) put forth various submissions, each with potential. The Vought submission in particular was based on their successful F-8 "Crusader" carrier-based strike fighter which became a proven USN contributor during the 1960s. Its airframe was modified slightly to include a shortened fuselage but retained its high-mounted, swept-back wings (though with greater span), tricycle undercarriage, and under-cockpit intake. The adjustable, pivoting wing mainplanes of the F-8 were dropped to simplify the new design for both production and maintenance/operation. After evaluation of all the competing types, the Vought submission was selected in February of 1964 and assigned the USN designation of "A-7" with the name of "Corsair II" - honoring the successful war-winning World War 2-era Vought F4U "Corsair" carrier-based, prop-driven product.
Development of the A-7 platform was relatively fast and three YA-7A developmental models were ordered by the USN in March of 1964. A first flight was recorded on September 26th, 1965 with the engine of choice being the Pratt & Whitney TF30-P-6 turbofan of 11,350 pounds thrust. Its non-afterburning engine decreased fuel consumption which adding operational range but limited speeds to the subsonic range. The initial design was also fitted with all-important radar in the nose via the AN/APQ-116 series system and a Head-Up Display (HUD) in the cockpit made it the first American aircraft to feature this useful, now standard, technology. An ejection seat increased pilot survivability and an advanced, digital weapons suit made for an accurate bomb-delivery platform when compared to contemporaries.
The wing mainplanes were hinged outboard of the hardpoints for improved carrier storage and the tricycle undercarriage designed with the rigors of carrier operation in mind. Underwing hardpoints numbered six in all (three to a wing) and two side-fuselage stations were also in play - mainly to carry AIM-9 "Sidewinder" short-range, Air-to-Air Missiles (AAMs). Total stores capability was theoretically 15,000 pounds made up of a mix of conventional drop bombs, guided ordnance, and homing/guided missiles. Initially 2 x 20mm Colt MK 12 cannons were fitted for close-in work and 250 rounds were afforded per gun installation. A later mark introduced a single 20mm rotary gun with 1,030 rounds carried.
With testing behind it, the YA-7A graduated to its first production form as the "A-7A" and these were taken into USN service in 1966 through Squadron VA-147. In 1967, Initial Operating Capability (IOC) was reached. The A-7 appeared at a time when the American military was firmly committed to actions in and around Vietnam. As such, the Corsair II's baptism of fire was quick to be seen as the aircraft was shipped to the theater in number. Its first sorties came during December of 1967 beginning a long and storied service life for the Vought product.