Heinemann's Hot-Rod

(AKA the "Scooter") Military aircraft design specification committees, being bureaucracies, have an eternal tendency to take all the numbers from an old specification, multiply by 1.5, and release these as the specification for the next generation aircraft. So it was during the depths of the Korean War in 1952, when the U.S. Navy released its requirements for a new attack plane. The Navy decided this could weigh as much as 30,000 lbs, in order to carry all the ordnance they wanted. The Douglas aircraft corporation (later McDonnell Douglas), in El Segundo, California put their best designer, a fellow named Ed Heinemann, on the project. Mr. Heinemann had a long and distinguished resume of very successful designs (e.g. the Douglas SBD Dauntless, the B-26 Invader, the AD Skyraider, and many others.) He had the sensation that this creeping "bigger, heavier, more complex, more expensive" progression was a dead end. After a survey of the type of fighting the Navy had been doing in Korea, and a thorough analyis of the state-of-the-art in jet engine development, he made a list of all the features that could be incorporated in the new plane, and then ruthlessly deleted everything that wasn't necessary for the designed mission of the aircraft. Then, he started drawing up a concept for an airplane that would become a legend. The resulting design astonished the authorities in BuAir, because it could meet their payload, range and performance requirements at no more than half the max weight in the specification. The Heinemann approach was to build the slickest, most efficient, minimally sized airframe around one of the new Wright J65 turbojet engines, which could produce up to 7,200 lbs. static thrust. Internal fuel capacity was by design sufficient only for the return from the target, the fuel for the journey to the target would be carried externally in streamlined drop tanks. Forget an internal bomb-bay, much too heavy and complicated - all ordnance would be carried externally underneath the plane attached to hard points on the wing. Forget RADAR, it's 1952, when any set with a helpful capability was far too heavy, and not that reliable, either. So the A-4 made do with a simple optical sight not much more advanced than what they had in WW II. For the cockpit design, take an average, five foot six guy, and wrap the cockpit around him like a SCUBA diver's wet-suit. The wing of the new plane was of the arrowhead shaped delta configuration, efficient at the transonic cruise velocities at which the aircraft would operate. Delta wings have problems at low speeds, though, so for landing approaches the wing incorporated large flaps and leading-edge slats. For simplicity, the slats were NOT operated hydraulically, but were raised and lowered entirely by the air-pressure impinging on the wings as airspeed and angle-of-attack changed. (Decades later, in the early 1980s, this noder had the privilege of flying the 2-seat trainer version of the Skyhawk...and was surprised during one hard-turning training dogfight when the slat on one wing popped out, but the other didn't. This meant that one wing was suddenly producing about three times the lift of the other, and the plane began rolling about its longitudinal axis about like a football does during a forward pass. My head banged back and forth against either side of the canopy like a bell-clapper, at which point I conceded the wisdom of those big, bulky white helmets. Fortunately, the furious rolling ceased when I let go of the stick, or that would have been the end of Ltjg ring_wraith!) The Skyhawk had a 20mm automatic cannon in each wing root, and could carry an astonishing variety of bombs, rockets, and missiles. The Navy began buying them in lots, and they were the front-line attack punch on aircraft carriers by 1960. The genius of the Skyhawk design, though, was the built in room for future development and improvement. A steady progression of design enhancements followed...engines got more powerful, and successive models of the A-4 had engines of 7,700, 8,200, 9,300, topping out at 11,200 lbs of thrust. (Later models had Pratt & Whitney J52 engines). This progression supported ever increasing payloads. The A-4 even gained a RADAR set, as the design of these became smaller and lighter, which allowed it to operate at night or in bad weather. Late versions featured a bizarre-looking hump along the dorsal spine of the plane behind the cockpit, in which was carried electronic jamming equipment, which, in light of experience (see below), was becoming urgently necessary.

The Skyhawk in service

And so, in 1964, when the U.S. destroyers Maddox and Turner Joy came under fire from North Vietnamese patrol boats (or thought they did, opinions still vary on this point,) and President Johnson ordered prompt retaliation, it was the A-4 Skyhawks that got the call. A-4s participated with the U.S. Navy and Marines for the duration of the ensuing conflict. For the most part, they performed excellently, but proved to have some vulnerability to the new Surface-to-Air missiles (SAM) deployed by the North. This motivated the development of ever more elaborate electronic warfare technology to avoid these. The Skyhawks added some jamming equipment, as described above, but the design ultimately reached its developmental limit as this technology began to take off. Also, no version of the A-4 was ever as capable at night and in bad weather as was starting to be required. The later phases of the war saw the Skyhawks superseded by the more advanced Vought A-7 Corsair II in Navy use from the carriers against the North, though the Skyhawks soldiered on with the Marines operating from land bases in the South in the close air support role. The Skyhawk was also widely exported, seeing service with the air forces of Australia, New Zealand, Singapore. The Israelis, most famously, made extensive use of them in the '70s, where they were a mainstay during the Yom-Kippur war. The Argentine air force used them to inflict some nasty surprises against the Royal Navy during the Falklands conflict of 1982. This noder was in training to become a U.S. navy pilot that year...I was actually flying the 2-seater version of the Skyhawks, and part of our training was low-level navigation and attacks. 350 knots at 500 feet of altitude will definitely open your eyes, but then I saw the TV footage of the Argie pilots flying in at 500 knots at probably 50 feet to deliver attacks on British destroyers. I am still in awe of the utter balls on display by these guys. After they were withdrawn from front-line fleet service in the U.S., the Skyhawk found a role as aggressor aircraft in training programs like Top Gun, because it closely approximated the tight-turning, hard-to-see characteristics of some of the Soviet MiG fighters. And, of course, the two-seat trainer version served on until finally replaced by a version of the British Aerospace Hawk. (I have documented another memorable hop in the TA-4 here.) Pretty much every pilot who has flown the A-4 has loved it. A formula one racer of a plane; you don't climb in it, you put it on. After a while, you have but to think of what you want, and the airplane does it. Over 3,000 of all versions were made.

Stats

Span: 27 ft 6 in Length: 40 ft 3.75 in. (excludes refueling probe, not present on all models). Wing Area: 260 sq. ft. Weight: empty, 10,465 lb., gross 24,500 lb. Performance: Max speed 670mph at sea level; initial rate of climb 8,440 ft/min; Tactical radius with 4,000 lb. ordnance load, 340 miles. Armament: 2 fixed forward-firing 20mm guns, up to 9,155 lbs. ordnance externally on 5 hard points. Source: Unitied States Navy Aircraft since 1911, second edition, Gordon Swanborough & Peter M. Bowers, Naval Institute press, 1968, ISBN 0-870210968-5.