Note that R.G. offered two different placements of the main landing wheels in his first concept drawing.
The development of the Douglas A4D started with a rough sketch by R.G. Smith.
Note that R.G. offered two different placements of the main landing wheels in his first concept drawing.
Tommy Thomason offers the below data:
A4D-1: OCT 1952, no refueling probe, no radar, three hard points. Re-designated the A-4A in OCT 1962.
A4D-2: MAR 1956, refueling probe, no radar, three hardpoints. Re-designated the A-4B in OCT 1962.
A4D-3: 1957, none built. Douglas proposal for a improved A4D-2. U.S. Navy never funded, project cancelled.
A4D-2N: AUG 1958, refueling probe, radar, three hardpoints. Compromise to the cancelled A4D-3 proposal, the "N" stood for "night capable". Re-designated the A-4C in OCT 1962.
A4D-4: 1958, none built. Douglas proposal for an engine upgrade. Not approved.
A4D-5: JUL 1961: refueling probe, fuselage changes, different engine, five hardpoints, some retrofitted with avionics hump. Re-designated the A-4E in OCT 1962. The A-4F (AUG66) was an improved "E", had the avionics hump, some received the bent refueling probe.
A4D-6: 1963, none built. Proposal for engine and airframe improvements that was in competition with the Ling-Temco-Vought A-7 Corsair II.
Skyhawk II: APR 1970, major upgrade specifically for U.S. Marine Corps. Designated the A-4M, bent fuel probe, canopy change, five hardpoints, drag chute, IFF ant on vertical fin.
