The Douglas A-4 Skyhawk is a carrier-capable light attack aircraft developed for the United States Navy and Marine Corps in the 1950s.
It was designed and produced by Douglas Aircraft Company and McDonnell Douglas.
The aircraft is relatively light, with a maximum take-off weight of 24,500 pounds and a top speed of 670 miles per hour.
Its five hardpoints support a variety of missiles, bombs, and munitions, and it can deliver nuclear weapons.
The Skyhawk played important roles in the Vietnam War, Yom Kippur War, and Falklands War.
To date, some of the 2,960 produced remain in service with the Argentine Air Force and Brazilian Naval Aviation.
Ed Heinemann of Douglas Aircraft created the Skyhawk in response to the United States Navy’s search for a jet-powered attack aircraft to replace the Douglas Skyraider.
Heinemann’s design was small, lightweight, and simple, resulting in an aircraft that weighed only half of the Navy’s weight requirement and had a compact wing that did not need to be folded for carrier storage.
The first 500 production units cost an average of $860,000 each, which was less than the Navy’s maximum of one million dollars.
The Skyhawk earned several nicknames due to its speed and nimble performance, including “Scooter,” “Kiddiecar,” “Bantam Bomber,” and “Tinker Toy Bomber.”
The XA4D-1 prototype set a world speed record of 695.163 mph on 15 October 1955.
With a low-mounted delta wing, tricycle undercarriage, and a single turbojet engine in the rear fuselage, the Skyhawk has a conventional post-World War II design.
Its tail is of cruciform design with the horizontal stabilizer mounted above the fuselage, and it has two air intakes on the fuselage sides.
The armament includes two 20 mm (.79 in calibre) Colt Mk 12 cannons, one in each wing root, with 100 rounds per gun.
Additionally, it carries a large variety of bombs, rockets, and missiles on a hardpoint under the fuselage centreline and hardpoints under each wing.
The Skyhawk’s leading-edge slats were designed to drop automatically at the appropriate speed by gravity and air pressure, saving weight and space by omitting actuation motors and switches.
Similarly, the main undercarriage did not penetrate the main wing spar, designed so that when retracted, only the wheel itself was inside the wing.
The rudder was constructed of a single panel reinforced with external ribs.
The A-4 pioneered the concept of “buddy” air-to-air refuelling, which allows the aircraft to supply others of the same type, reducing the need for dedicated tanker aircraft.
This procedure greatly improves operational flexibility and reassurance against the loss or malfunction of tanker aircraft, though it reduces the effective combat force on board the carrier.
A designated supply A-4 would mount a centre-mounted “buddy store,” a large external fuel tank with a hose reel in the aft section and an extensible drogue refuelling bucket.
The Navy issued a contract for the type on 12 June 1952, and the first prototype first flew from Edwards Air Force Base, California on 22 June 1954.
Deliveries to Navy and Marine Corps squadrons commenced in late 1956.
The Skyhawk remained in production until 1979, with 2,960 aircraft built, including 555 two-seat trainers.
The last production A-4, an A-4M of Marine squadron, had the flags of all nations that operated the A-4 painted on its fuselage sides.
The Skyhawk’s legacy is one of great innovation and efficiency, making it a beloved aircraft to this day. Variants Original production variants XA4D-1 Initial prototype, one built. YA4D-1 Flight test prototypes and pre-production aircraft; redesignated YA-4A in 1962, then A-4A, 19 built. A4D-1 (A-4A) Initial production version; redesignated A-4A in 1962, 166 built. A4D-2 (A-4B) Strengthened aircraft and added air-to-air refuelling capabilities, improved navigation and flight control systems, provision for AGM-12 Bullpup missile; redesignated A-4B in 1962, 542 built. A4D-2N (A-4C) Night/adverse weather version of A4D-2, with AN/APG-53A radar, autopilot, LABS low-altitude bombing system. Wright J65-W-20 engine with 8,200 lbf (36 kN) of take-off thrust; redesignated A-4C in 1962, 638 built. A4D-3 Proposed advanced avionics version, none built. A4D-4 Proposed long-range version with new wings; none built. A4D-5 (A-4E) Major upgrade, including new Pratt & Whitney J52-P-6A engine with 8,500 lbf (38 kN) of thrust, strengthened airframe with two more weapon pylons (for a total of five), improved avionics, with TACAN, Doppler navigation radar, radar altimeter, toss-bombing computer, and AJB-3A low-altitude bombing system. Many later upgraded with J52-P-8 engine with 9,300 lbf (41 kN) thrust; redesignated A-4E in 1962, 499 built. A4D-6 Proposed enlarged version of the A4D-5, none built. A-4F Refinement of A-4E with extra avionics housed in a hump on the fuselage spine (this feature later retrofitted to A-4Es and some A-4Cs), wing-top spoilers to reduce landing roll out, nose wheel steering, and more powerful J52-P-8A engine with 9,300 lbf (41 kN) of thrust, later upgraded in service to J52-P-408 with 11,200 lbf (50 kN), 147 built. Some served with Blue Angels acrobatic team from 1973 to 1986. A-4G Eight aircraft built new for the Royal Australian Navy with minor variations from the A-4F; in particular, they were not fitted with the avionics “hump”. Subsequently, eight more A-4Fs were modified to this standard for the RAN. Significantly the A-4G were modified to carry four underwing Sidewinder AIM-9B missiles increasing their Fleet Defence capability. Sold in 1984 to the Royal New Zealand Air Force and later rebuilt in Project KAHU as A-4Ks. A-4H 90 aircraft for the Israeli Air Force based on the A-4F. Used 30 mm (1.18 in) DEFA cannon with 150 rpg in place of U.S. 20 mm (.79 in) guns. Later, some A-4Es later locally modified to this standard. Subsequently, modified with extended jet pipes as protection against heat-seeking missiles. A-4K 10 aircraft for Royal New Zealand Air Force. In the 1990s, these were upgraded under Project KAHU with new radar and avionics, provision for AGM-65 Maverick, AIM-9 Sidewinder, and GBU-16 Paveway II laser-guided bomb. The RNZAF also rebuilt an A-4C and 10 A-4Gs to A-4K standard. A-4M Skyhawk II Dedicated Marine version with improved avionics and more powerful J52-P-408 engine with 11,200 lbf (50 kN) thrust, enlarged cockpit, IFF system. Later fitted with Hughes AN/ASB-19 Angle Rate Bombing System (ARBS) with TV and laser spot tracker, 158 built. A-4N 117 modified A-4Ms for the Israeli Air Force. TA-4F Conversion trainer – standard A-4F with extra seat for an instructor, 241 built. TA-4G two trainer versions of the A-4G built new, and two more modified from TA-4Fs. TA-4H 25 trainer versions of the A-4H. Upgraded with more modern avionics. TA-4J Dedicated trainer version based on A-4F, but lacking weapons systems, and with down-rated engine, 277 built new, and most TA-4Fs were later converted to this configuration. TA-4K Four trainer versions of the TA-4J. A fifth, non-flying display example was later assembled in NZ from spare parts. Upgraded, modified and export variants. TA-4E Two A-4Es modified as prototypes of a trainer version. EA-4F Four TA-4Fs converted for ECM training. A-4L 100 A-4Cs remanufactured for Marine Corps Reserves and Navy Reserve squadrons. Fitted with A-4F avionics (including the fuselage “hump”) but retaining J-65 engine and three-pylon wing. OA-4M 23 TA-4Fs modified for Forward Air Control duties. A-4P Remanufactured A-4Bs sold to Argentine Air Force, known as A-4B by the Argentines. A-4Q Remanufactured A-4Bs sold to Argentine Navy. A-4Y Provisional designation for A-4Ms modified with the ARBS. Designation never adopted by the U.S. Navy or U.S. Marine Corps. A-4AR Fightinghawk 36 A-4Ms refurbished for Argentina. OA-4AR Fightinghawk Refurbished two-seat training version for Argentina. CA-4F A proposed two seat variant for the Royal Canadian Navy based on the A-4E with a dorsal conformal fuel tank instead of an avionics hump, it was to have replaced the F2H-3 Banshee on HMCS Bonaventure. Canada expressed little interest and so it was never placed in production. A-4KU 30 modified A-4Ms for the Kuwaiti Air Force. Brazil purchased 20 of these second-hand and redesignated them AF-1. Now used by the Brazilian Navy on carrier duty. TA-4KU Three trainer versions of the above. Brazil purchased some of these second-hand and redesignated them AF-1A. A-4PTM 40 A-4Cs and A-4Ls refurbished for Royal Malaysian Air Force, incorporating many A-4M features (PTM stands for Peculiar to Malaysia). TA-4PTM Unique trainer version for Royal Malaysian Air Force. Converted from A-4C/L airframes with 28″ fuselage plug and second cockpit, similar to TA-4F/J (PTM stands for Peculiar to Malaysia). A-4S 50 A-4Bs remanufactured for Republic of Singapore Air Force. TA-4S Seven trainer versions of the above. Different from most TA-4 trainers with a common cockpit for the student and instructor pilot, these were essentially rebuilt with a 28 in (710 mm) fuselage plug inserted into the front fuselage and a separate bulged cockpit (giving better all-round visibility) for the instructor seated behind the student pilot. A-4S-1 50 A-4Cs remanufactured for the Republic of Singapore Air Force. TA-4S-1 Eight trainer versions of the above. These were designated as TA-4S-1 to set it apart from the earlier batch of seven airframes. A-4SU Super Skyhawk Extensively modified and updated version of the A-4S-1, exclusively for the Republic of Singapore Air Force, fitted with a General Electric F404 non-afterburning turbofan engine, and modernized electronics. TA-4SU Super Skyhawk Extensively modified and updated version of the TA-4S & TA-4S-1 to TA-4SU standard. AF-1/1A Brazilian Navy designation applied to 23 A-4KU and TA-4KU aircraft acquired from the Kuwaiti Air Force. AF-1B/C Brazilian Navy upgraded version of AF-1/1A by Embraer and AEL Sistemas. Changes from analogue to digital avionics, new radar systems, improved communications equipment and weapons. Specifications Crew 1 Length 40 ft 1.5 in (12.230 m). Wingspan 27 ft 6 in (8.38 m). Height 15 ft 2 in (4.62 m). Wing area 260 sq ft (24 m2). Airfoil Root NACA 0008-1.1-25. Tip NACA 0005-.825-50. Empty weight 9,853 lb (4,469 kg). Gross weight 16,216 lb (7,355 kg). Max take-off weight 24,500 lb (11,113 kg). Powerplant 1 × Pratt & Whitney J52-P-6A turbojet engine, 8,500 lbf (38 kN) thrust. Performance Maximum speed 585 kn (673 mph, 1,083 km/h) at sea level. Range 1,008 nmi (1,160 mi, 1,867 km). Ferry range 2,194 nmi (2,525 mi, 4,063 km). G limits +8 -3. Rate of climb 5,750 ft/min (29.2 m/s). Wing loading 62.4 lb/sq ft (305 kg/m2). Thrust/weight 0.526 (at gross weight). Armament Guns 2× 20 mm (0.79 in) Colt Mk 12 cannon, 100 rounds/gun. Hardpoints 4 × under-wing & 1× under-fuselage pylon stations with a capacity of 8,500 lb (3,900 kg),
With provisions to carry combinations of: Rockets 4× LAU-10 rocket pods (each with 4× 127 mm Mk 32 Zuni rockets). Bombs 6× Rockeye-II Mark 20 Cluster Bomb Unit (CBU). 6× Rockeye Mark 7/APAM-59 CBU. Mark 80 series of unguided bombs (including 3 kg and 14 kg practice bombs). B43 nuclear bomb. B57 nuclear bomb. B61 nuclear bomb. Other Up to 3× 370 US gallons (1,400 L) Sargent Fletcher drop tanks for ferry flight/extended range/loitering time. Missiles Air-to-air missiles: 4× AIM-9 Sidewinder. Air-to-surface missiles: 2× AGM-12 Bullpup. 2× AGM-45 Shrike anti-radiation missile. 2× AGM-62 Walleye TV-guided glide bomb. 2× AGM-65 Maverick. Avionics Typical avionics fitted to A-4s. Bendix AN/APN-141 Low altitude radar altimeter (refitted to C and E, standard in the F) Stewart-Warner AN/APQ-145 Mapping & Ranging radar (mounted on A-4F, also found on A-4E/N/S/SU).
Sources American Attack Aircraft Since 1926, E R Johnson. Images of War, United States Naval Aviation 1911-2014-Michael Green. McDonnell Douglas aircraft since 1920: Volume I-René J Francillon. San Diego Air and Space Museum Archive. The National Museum of the U.S. Air Force. US Marine Corps Aviation, 75th Year of Naval Aviation, Vol 5. United States Navy Aircraft Since 1911-Gordon Swanborough & Peter M Bowers.