A study in simplicity, the A-4 Skyhawk resulted from Douglas Aircraft Company designer Ed Heinemann's concern about the increasing weight and cost of combat aircraft appearing during the 1950s. The A-4 ran counter to this trend, incorporating a small delta wing that eliminated the need for a heavy wing-folding mechanism for improved storage aboard aircraft carriers. Additionally, engineers reduced the number of cockpit components and redesigned the pilot ejection system in order to reduce weight.
Other measures included elimination of a heavy duty battery in favor of a fuselage stored wind driven generator, the removal of a back-up hydraulic system through use of gravity-dropped landing gear, and installation of a simplified air conditioning system that was one third the weight of those then available. In final form, the 'Tinker Toy,' as pilots knew the A-4, bettered the Navy's maximum weight restriction by more than half.
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