The Douglas A-4 Skyhawk can only take off carrying less than a ton.
A4D-2 [A-4B]Strengthened aircraft and added air-to-air refueling capabilities, improved navigation and flight control systems, provision for AGM-12 Bullpup missile; redesignated A-4B in 1962, 542 built
A-4M Skyhawk IIDedicated Marine version with improved avionics and more powerful J52-P-408 engine with 11,200 lbf (50 kN) thrust, enlarged cockpit, IFF system

