Douglas A-4 Skyhawk

https://en.wikipedia.org/wiki/Douglas_A-4_Skyhawk

The Douglas A-4 Skyhawk is a single-seat subsonic carrier-capable attack
aircraft developed for the United States Navy and United States Marine Corps in
the early 1950s. The delta-winged, single turbojet engined Skyhawk was designed
and produced by Douglas Aircraft Company, and later by McDonnell Douglas. It was
originally designated A4D under the U.S. Navy's pre-1962 designation system.

The Skyhawk is a relatively lightweight aircraft with a maximum takeoff weight
of 24,500 pounds (11,100 kg) and has a top speed of more than 670 miles per hour
(1,080 km/h). The aircraft's five hardpoints support a variety of missiles,
bombs and other munitions. It is capable of carrying a bomb load equivalent to
that of a World War II–era Boeing B-17 bomber, and can deliver nuclear weapons
using a low-altitude bombing system and a "loft" delivery technique. The A-4 was
originally powered by the Wright J65 turbojet engine; from the A-4E onwards, the
Pratt & Whitney J52 engine was used.

Skyhawks played key roles in the Vietnam War, the Yom Kippur War, and the
Falklands War. Sixty years after the aircraft's first flight in 1954, some of
the 2,960 produced (through February 1979) remain in service with the Argentine
Air Force.

The Skyhawk was designed by Douglas Aircraft's Ed Heinemann in response to a
U.S. Navy call for a jet-powered attack aircraft to replace the older Douglas AD
Skyraider (later redesignated A-1 Skyraider). Heinemann opted for a design that
would minimize its size, weight, and complexity. The result was an aircraft that
weighed only half of the Navy's weight specification. It had a wing so compact
that it did not need to be folded for carrier stowage. The first 500 production
examples cost an average of $860,000 each, less than the Navy's one million
dollar maximum. The diminutive Skyhawk soon received the nicknames "Scooter",
"Kiddiecar", "Bantam Bomber", "Tinker Toy Bomber", and, on account of its speed
and nimble performance, "Heinemann's Hot-Rod". The XA4D-1 prototype set a world
speed record of 695.163 mph on October 15, 1955.

The aircraft is of conventional post-World War II design, with a low-mounted
delta wing, tricycle undercarriage, and a single turbojet engine in the rear
fuselage, with two air intakes on the fuselage sides. The tail is of cruciform
design, with the horizontal stabilizer mounted above the fuselage. Armament
consisted of two 20 mm (.79 in caliber) Colt Mk 12 cannons, one in each wing
root, with 100 rounds per gun (the A-4M Skyhawk II and types based on the A-4M
have 200 rounds per gun), plus a large variety of bombs, rockets, and missiles
carried on a hardpoint under the fuselage centerline and hardpoints under each
wing (originally one per wing, later two).

The short-span delta wing did not require the complexity of wingtip folding,
saving an estimated 200 pounds (91 kg). Its spars were machined from a single
forging that spanned across both wingtips. The 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 and the undercarriage struts
were housed in a fairing below the wing. Thus the wing structure was lighter
with the same overall strength. The rudder was constructed of a single panel
reinforced with external ribs.

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 VMA-331 had the flags of all nations that operated the A-4 painted on
its fuselage sides.


Role
Attack aircraft, fighter, aggressor aircraft

National origin
United States

Manufacturer
Douglas Aircraft Company
McDonnell Douglas

First flight
22 June 1954; 65 years ago

Introduction
1 October 1956; 62 years ago

Retired
USMC (1998), U.S. Navy (2003)
Israeli Air Force (2015)
Royal New Zealand Air Force (2001)

Status
In limited service with non-U.S. users

Primary users
United States Navy (historical)
United States Marine Corps (historical)
Israeli Air Force (historical)
Argentine Air Force (historical)

Produced
1954–1979

Number built
2,960

Unit cost

US$2.8–3.8 million


Variants
Lockheed Martin A-4AR Fightinghawk
McDonnell Douglas A-4G Skyhawk
ST Aerospace A-4SU Super Skyhawk

The Skyhawk proved to be a relatively common United States Navy aircraft export
of the postwar era. Due to its small size, it could be operated from the older,
smaller World War II-era aircraft carriers still used by many smaller navies
during the 1960s. These older ships were often unable to accommodate newer Navy
fighters such as the F-4 Phantom II and F-8 Crusader, which were faster and more
capable than the A-4, but significantly larger and heavier than older naval
fighters.

The Navy operated the A-4 in both Regular Navy and Naval Reserve light attack
squadrons (VA). Although the A-4's use as a training and adversary aircraft
would continue well into the 1990s, the Navy began removing the aircraft from
its frontline attack squadrons in 1967, with the last ones (Super Foxes of
VA-55/212/164) being retired in 1976.

The Marine Corps would not take the U.S. Navy's replacement warplane, the LTV
A-7 Corsair II, instead keeping Skyhawks in service with both Regular Marine
Corps and Marine Corps Reserve attack squadrons (VMA), and ordering the new A-4M
model. The last USMC Skyhawk was delivered in 1979, and they were used until the
mid-1980s before they were replaced by the equally small, but more versatile
STOVL AV-8 Harrier.

Vietnam War era

Skyhawks were the U.S. Navy's primary light attack aircraft used over North
Vietnam during the early years of the Vietnam War; they were later supplanted by
the A-7 Corsair II in the U.S. Navy light attack role. Skyhawks carried out some
of the first air strikes by the US during the conflict, and a Marine Skyhawk is
believed to have dropped the last American bombs on the country. Notable naval
aviators who flew the Skyhawk included Lieutenant Commanders Everett Alvarez,
Jr. and John McCain, and Commander James Stockdale. On 1 May 1967, an A-4C
Skyhawk piloted by Lieutenant Commander Theodore R. Swartz of VA-76 aboard the
carrier USS Bon Homme Richard, shot down a North Vietnamese Air Force MiG-17
with an unguided Zuni rocket as the Skyhawk's only air-to-air victory of the
Vietnam War.

From 1956 on, Navy Skyhawks were the first aircraft to be deployed outside of
the U.S. armed with the AIM-9 Sidewinder. On strike missions, which was the
Skyhawk's normal role, the air-to-air armament was for self-defense purposes.

During the war, 362 A-4/TA-4F Skyhawks were lost due to all causes. The U.S.
Navy lost 271 A-4s, the U.S. Marine Corps lost 81 A-4s and 10 TA-4Fs. A total of
32 A-4s were lost to surface-to-air missiles (SAMs), and one A-4 was lost in
aerial combat to a MiG-17 on 25 April 1967.

Specifications (A-4D-5 / A-4E Skyhawk)

General characteristics
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 takeoff 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
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

Armament

Guns: 2× 20 mm (0.79 in) Colt Mk 12 cannon, 100 rounds/gun
Rockets:
4× LAU-10 rocket pods (each with 4× 127 mm Mk 32 Zuni rockets)

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


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

Others: up to 3× 370 US gallons (1,400 L) Sargent Fletcher drop tanks (pylon
stations 2, 3, 4 are wet plumbed) for ferry flight/extended range/loitering time
Douglas Escapac 1 (A-4A, B, C, & E) and 1A-1 (A-4A, B, C, & E) ejection seat


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)
UHF AN/ARC-159
VHF AN/ARC-114
RAD/ALT AN/APN-194
TACAN AN/ARN-118
ILS/VOR AN/ARA-63 / AN/ARN-14
CHAFF AN/ALE-39
IFF AN/APX-72
RADAR AN/APG-53-A
Secure Comm AN/KY28/58
Countermeasures AN/ALQ-126
Countermeasures AN/ALQ-162
HUD AN/AVQ-24
Navigational Computer AN/ASN-41




*