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Designed to deliver a tactical nuclear weapon, the lightweight delta winged A4D Skyhawk single seat attack bomber weighed in at 15,000 pounds gross weight and 7,400 pounds empty. A-4Bs Refueling over the USS Intrepid
A4D-2 Skyhawks 3 in Banking Formation
Produced by Douglas Aircraft Company in California, USA, its first flights were in June 1954 and first delivered in September-October 1956 to squadron VA-72. Production and delivery of a succession of newer model A4's continued until 1979, over 25 years.
Models include A-4A (A4D-1 was old designation), A-4B, A-4C, A-4E, A-4F, A-4H, A-4K, A-4L, A-4N and A-4M.
Ed Heinemann chief engineer at Douglas designed the small lightweight aircraft to haul twice it's own weight. Nicknames included Heinemann's Hot Rod, The Scooter, Tinker Toy and Kiddiecar.

Thirty one A-4's made the first strike in North Vietnam in August 1964. During the Vietnam War, a total of 362 Skyhawks were lost to accidents and enemy action by the U.S. Navy and Marine Corps. The first officially sold planes to Israel in 1967 were 48 A4-H's which were involved in several skirmishes.
Specifications comparing the early A-4A and the latest A-4M are following.