North American A-5b Vigilante

The North American A-5 Vigilante was a powerful, highly advanced carrier-based supersonic bomber designed for the United States Navy. Its service in the nuclear strike role to replace the A-3 Skywarrior was very short. As the RA-5C, it saw extensive service during the Vietnam War in the reconnaissance role. Prior to the unification of the Navy designation sequence with the Air Force sequence in 1962, it was designated the A3J Vigilante.

Design and development

In 1953, North American Aviation began a private study for a carrier-based, long-range, all-weather strike bomber, capable of delivering nuclear weapons at supersonic speeds. This proposal, the NAGPAW (North American General Purpose Attack Weapon) concept, was accepted by the United States Navy, with some revisions, in 1955. A contract was awarded on 29 August 1956. Its first flight occurred two years later on 31 August 1958 in Columbus, Ohio.

At the time of its introduction, the Vigilante was one of the largest and by far the most complex aircraft to operate from a United States Navy aircraft carrier. It had a high-mounted swept wing with a boundary-layer control system (blown flaps) to improve low-speed lift, aluminum-lithium alloy for wing skins and titanium for critical structures. It had two widely-spaced General Electric J79 turbojet engines (the same as used on the F-4 Phantom II fighter), and a single large vertical tailfin. The wings, the tail, and the nose radome folded for carrier stowage. The Vigilante had a crew of two seated in tandem, a pilot and a bombardier-navigator (BN)—reconnaissance/attack navigator (RAN) on later recon versions in individual ejection seats.

It was surprisingly agile for such a big and heavy aircraft. Without the drag of bombs or missiles, even escorting fighters found that the clean airframe and powerful engines made the Vigilante very fast at high altitudes. Its high landing speed made returning to the carrier a challenge for inexperienced or unwary pilots.

The Vigilante had extremely advanced and complex electronics. It had one of the first fly-by-wire systems of an operational aircraft (with mechanical/hydraulic backup) and a computerized AN/ASB-12 nav/attack system incorporating a head-up display (Pilot's Projected Display Indicator (PPDI), one of the first), multi-mode radar, Radar-Equipped Inertial Navigation System (REINS, based on technologies developed for the Navaho missile), closed-circuit television camera under the nose, and an early digital computer known as VERDAN (Versatile Digital Analyzer) to run it all. Although this system was highly sophisticated, the technology was in its infancy, and its reliability was poor. In early squadron service the system's MTBF (Mean Time Between Failures) was only 15 minutes.[citation needed] Although some bugs were worked out, the aircraft remained a maintenance nightmare throughout its career.

Its main armament was carried in a novel linear bomb bay between the engines in the rear fuselage which was intended to make bomb delivery safer and more accurate. When conventional bombers "drop" a bomb, the bomb falls downward, but continues forward at the same speed as the aircraft. This requires pilot skill and complicated equipment to place a bomb on its intended target. The linear bomb bay would eject the payload rearward at approximately the same speed as the forward velocity of the aircraft, causing the bomb to "stand still" and drop straight down. No calculation is needed - the bomb falls at the point at which it was dropped. As an added benefit, the aircraft is rapidly moving away from the dropped bomb, enabling lower drop altitudes or safer drops from higher altitudes.[citation needed]

The single nuclear weapon, commonly the Mk 28 bomb, was attached to two disposable fuel tanks in the cylindrical bay in an assembly known as the "stores train." The idea was for the fuel tanks to be emptied during flight to the target and then jettisoned as part of the bomb by an explosive drogue gun. In practice the system was never reliable and no live weapons were ever carried in the linear bomb bay. In the RA-5C configuration, the bay was used solely for fuel. On three occasions the shock of the catapult launch caused the fuel cans to eject onto the deck resulting in one aircraft loss.[1]

The Vigilante originally had two wing pylons, intended primarily for drop tanks.

The second Vigilante mark, the A3J-2 (A-5B), incorporated internal tanks for an additional 460 gallons of fuel (which added a pronounced dorsal "hump") along with two additional wing hardpoints, for a total of four. In practice the hardpoints were rarely used. Other improvements included blown flaps on the leading edge of the wing and sturdier landing gear.[citation needed]

The reconnaissance version of the Vigilante, the RA-5C, had slightly greater wing area and added a long canoe-shaped fairing under the fuselage for a multi-sensor reconnaissance pack. This added an APD-7 side-looking airborne radar (SLAR), AAS-21 infrared linescanner, and camera packs, as well as improved ECM. An AN/ALQ-61 electronic intelligence system could also be carried. The RA-5C retained the AN/ASB-12 bombing system, and could, in theory, carry weapons, although it never did in service. Later-build RA-5Cs had more powerful -10 engines with afterburning thrust of 17,900 lbf (80 kN). The reconnaissance Vigilante weighed almost five tons more than the strike version with almost the same thrust and an only modestly enlarged wing. These changes cost it acceleration and climb rate, though it remained fast in level flight.

[edit] Operational history

Designated A3J-1, the Vigilante first entered squadron service with Heavy Attack Squadron THREE (VAH-3) in June 1961 at NAS Sanford, Florida, replacing the A-3 Skywarrior in the heavy attack role. All variants of the Vigilante were built at North American Aviation's facility at Port Columbus Airport in Columbus, Ohio, alongside the T-2 Buckeye and OV-10 Bronco.

Under the Tri-Services Designation plan implemented under Robert McNamara in September 1962, the Vigilante was redesignated A-5, with the initial A3J-1 becoming A-5A and the updated A3J-2 becoming A-5B. The subsequent reconnaissance version, originally A3J-3P, became the RA-5C.
An overhead aerial view of an RA-5C Vigilante aircraft.

The Vigilante's early service proved troublesome, with many teething problems for its advanced systems. It also arrived in service during a major policy shift in the U.S. Navy's strategic role, which switched to emphasize submarine launched ballistic missiles rather than manned bombers. As a result, in 1963, procurement of the A-5 was ended and the type was converted to the fast reconnaissance role. The first RA-5C's were delivered to the Replacement Air Group (RAG)/Fleet Replacement Squadron (FRS), Reconnaissance Attack Squadron THREE (RVAH-3) at NAS Sanford, Florida in July 1963, with all Vigilante squadrons subsequently redesignated RVAH. Under the cognizance of Reconnaissance Attack Wing ONE, a total of 10 RA-5C squadrons were ultimately commissioned. RVAH-3 continued to be responsible for the stateside-based RA-5C training mission of both flight crews, maintenance and support personnel, while RVAH-1, RVAH-5, RVAH-6, RVAH-7, RVAH-9, RVAH-11, RVAH-12, RVAH-13 and RVAH-14 routinely deployed aboard Forrestal, Saratoga, Ranger, Independence, Kitty Hawk, Constellation, Enterprise, America, John F. Kennedy and eventually Nimitz-class aircraft carriers to the Atlantic, Mediterranean and Western Pacific.
RA-5C Vigilante, BuNo 156608, from Reconnaissance Attack Squadron 7 (RVAH-7) during what may have been its final flight in 1979. This aircraft is now on permanent display at Naval Support Activity Mid-South (formerly NAS Memphis), TN.
RVAH-11 USS Kitty Hawk 1968

Eight of ten squadrons of RA-5C Vigilantes also saw extensive service in Vietnam starting in August 1964, carrying out hazardous medium-level reconnaissance missions. Although it proved fast and agile, 18 RA-5Cs were lost in combat: 14 to anti-aircraft fire, three to surface-to-air missiles, and one to a MiG-21 during Operation Linebacker II. Nine more were lost in operational accidents while serving with Task Force 77. Due, in part, to these combat losses, 36 additional RA-5C aircraft were built from 1968–1970 as attrition replacements.

In 1968, Congress closed the aircraft's original operating base of NAS Sanford, Florida and transferred the parent wing, Reconnaissance Attack Wing ONE, all subordinate squadrons and all aircraft and personnel to Turner AFB, a Strategic Air Command (SAC) B-52 and KC-135 base in Albany, Georgia. The tenant SAC bomb wing was then deactivated and control of Turner AFB was transferred from the Air Force to the Navy with the installation renamed NAS Albany. In 1974, after barely six years of service as a naval air station, Congress opted to close NAS Albany as part of a post-Vietnam force reduction, transferring all RA-5C units and personnel to NAS Key West, Florida.

Despite the Vigilante's useful service, it was expensive and complex to operate and occupied significant amounts of precious flight deck and hangar deck space aboard both conventional and nuclear-powered aircraft carriers. With the end of the Vietnam War, disestablishment of RVAH squadrons began in 1974, with the last Vigilante squadron, RVAH-7, completing its final deployment to the Western Pacific aboard USS Ranger (CV-61) in late 1979. Reconnaissance Attack Wing ONE was subsequently disestablished at NAS Key West, Florida in January 1980.

The Vigilante did not end the career of the A-3 Skywarriors, which would carry on as electronic warfare platforms and tankers, designated as EA-3B and KA-3B. Fighters replaced the RA-5C in the carrier-based reconnaissance role, with the F-8 Crusader modified with internal cameras and designated RF-8G, while select models of the F-14 Tomcat would carry the multi-sensor Tactical Air Reconnaissance Pod (TARPS) and the Digital Tactical Air Reconnaissance Pod (D-TARPS). Following up to present day, the weight of fighters such as the F-14 Tomcat and F/A-18E/F Super Hornet have evolved into the same 62,950 lb (28,550 kg) class as the Vigilante. With the retirement of the F-14, the F/A-18E and F/A-18F Super Hornet strike fighters and EA-18G Growler electronic warfare aircraft are planned to cover the strike, reconnaissance, tanker and electronic warfare roles of the F-14 Tomcat, A-6E Intruder, A-7E Corsair II, RF-8G Crusader, RA-5C, KA-6D Intruder, EA-6B Prowler. S-3B Viking, ES-3A Shadow and EA-3B Skywarrior.

Although the Vigilante served in the attack and reconnaissance roles, its design and configuration was believed to be a major influence on one of the world's most famous postwar interceptors: the Soviet MiG-25 "Foxbat" was apparently heavily influenced by the A-5's design. [2] The MiG-25 would look even more familiar if the Vigilante had retained the twin vertical fins of the prototype; although North American originally specified two fins, that part of the design was vetoed by the Navy in favor of one folding tailfin. Dual tailfins would become part of the U.S. Navy's F-14 Tomcat, the US Navy's and U.S. Marine Corps' F/A-18 Hornet) and the U.S. Air Force's F-15 Eagle and F-22 Raptor. The F-14, F-15 Eagle and other Western aircraft would also adopt a high mounted wing and wedge-shaped intake geometry (i.e., wedged air inlets) that were incorporated in the RA-5C.

[edit] Records

On 13 December 1960, Navy Commander Leroy Heath (Pilot) and Lieutenant Larry Monroe (Bombardier/Navigator) established a world altitude record of 91,450.8 feet (27,874.2 m) in an A3J Vigilante carrying a 1,000 kilogram payload, besting the previous record by over four miles (6 km). This new record held for over 13 years.

[edit] Variants

* YA3J-1 : Prototypes, two built.
* A3J-1 (A-5A): 59
* A3J-2 (A-5B): Six
* A3J-3P (RA-5C): Reconnaissance version, 91 new-build plus 43 converted A-5As
* ???-?? (A-5C): Proposed Improved Manned Interceptor (IMI) for U.S. Air Force with three engines; North American Rockwell Charge Number NR-349

[edit] Survivors
RA-5C BuNo 151629 on display at the Pueblo Weisbrod Aircraft Museum in Pueblo, Colorado in November 2007
RA-5C Vigilante, BuNo 156632, on display at Orlando Sanford International Airport (former NAS Sanford) in late March 2008
RA-5C BuNo 156632 on display at Orlando Sanford International Airport (former NAS Sanford) in May 2005

Several Vigilantes are currently stored or on display in the United States.

* A-5A Bureau Number (BuNo) 146697, the oldest Vigilante on display and the only one still in its original A3J/A-5A nuclear attack bomber configuration, is on display at Naval Air Station Patuxent River, Maryland.
* RA-5C BuNo 149289 is on display at the Pima Air & Space Museum in Tucson, Arizona. It was transferred from long-term storage at nearby Davis-Monthan Air Force Base and carries the markings of RVAH-3.
* RA-5C BuNo 151629 is on display at the Pueblo Weisbrod Aircraft Museum (formerly Fred E. Weisbrod Museum/International B-24 Museum) in Pueblo, Colorado. It is displayed in the markings of RVAH-3.
* RA-5C BuNo 156608 is on static display at Naval Support Activity Mid-South, formerly Naval Air Station Memphis, Tennessee. It was the last operational RA-5C aircraft and carries the markings of its last squadron, RVAH-7, during its final deployment aboard USS Ranger in 1979.
* RA-5C BuNo 156612 is on static display at Naval Air Station Key West, Florida and serves as a gate guard just inside the main gate. It carries the markings of RVAH-3.
* RA-5C BuNo 156621 was initially on display at the former U.S. Naval Photographic School at NAS Pensacola, Florida. It was then barged up the eastern Atlantic coast and was formerly on display on the USS Intrepid Museum in New York City. In 2005, the aircraft was acquired by New York State Aerosciences Museum (ESAM) in Glenville, New York. The aircraft suffered minor damage to its fuselage aft of the wing root while being moved from the aircraft carrier Intrepid to a barge while supported by slings. It is currently undergoing restoration for display. It carries the markings of the RA-5C Fleet Replacement Squadron (FRS), RVAH-3.
* RA-5C BuNo 156624 in on display at the National Museum of Naval Aviation at NAS Pensacola, Florida. It is displayed in the markings of RVAH-6, per that squadron's final cruise aboard the USS Nimitz in 1978.
* RA-5C BuNo 156632 was placed on display at the Orlando Sanford International Airport (ex-Naval Air Station Sanford) in Sanford, Florida in 2004 as a memorial to Vigilante aircrews and support personnel who served at NAS Sanford. It was transferred from the Naval Air Systems Command (NAVAIR) Weapons Division at Naval Air Weapons Station China Lake, California and is marked as an RVAH-3 aircraft.
* RA-5C BuNo 156638 is on display at Naval Air Station Fallon, Nevada. It was transferred from Naval Air Weapons Station China Lake, California and is marked as an RVAH-12 aircraft.
* RA-5C BuNo 156640 is currently in storage at the Naval Air Weapons Station China Lake, California.
* RA-5C BuNo 156641 is on display at the USS Midway Museum in San Diego, California. It carries the markings of RVAH-12.
* RA-5C BuNo 156643, the last Vigilante built, is on display at the Patuxent River Naval Air Museum in Patuxent River, Maryland. It was transferred from NAS Key West, Florida, and is displayed as a test aircraft operated by the Patuxent River Flight Test Division in the 1970s.

[edit] Operators

United States

* United States Navy

[edit] Specifications (A-5A Vigilante)
Orthographically projected diagram of the A-5A Vigilante.

General characteristics

* Crew: 2
* Length: 76 ft 6 in (23.32 m)
* Wingspan: 53 ft 0 in (16.15 m)
* Height: 19 ft 5 in (5.9 m)
* Wing area: 754 ft² (70 m²
* Empty weight: 32,700 lb (14,800 kg)
* Loaded weight: 47,530 lb (21,580 kg)
* Useful load: 30,250 lb (13,730 kg)
* Max takeoff weight: 62,950 lb (28,580 kg)
* Powerplant: 2× General Electric J79-GE-8 afterburning turbojets
o Dry thrust: 10,900 lbf (48 kN) each
o Thrust with afterburner: 17,000 lbf (76 kN) each

Performance

* Maximum speed: Mach 2.0 (1,320 mph, 2,123 km/h) at altitude
* Range: 1,290 mi (2,075 km)
* Service ceiling: 52,100 ft (15,880 m)
* Rate of climb: 8,000 ft/min (40.6 m/s)
* Wing loading: 80.4 lb/ft² (308.3 kg/m²
* Thrust/weight: 0.72

Armament

* Bombs:
o 1× B28 or B43 freefall nuclear bomb in internal weapons bay
o 2× B43, Mark 83, or Mark 84 bombs on two external hardpoint