Vietnam/Cold War: Grumman A-6 Intruder

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Grumman A-6 Intruder. Photograph Source: Public Domain

Grumman A-6E Intruder - Specifications:

General

  • Length: 54 ft., 7 in.
  • Wingspan: 53 ft.
  • Height: 15 ft. 7 in.
  • Wing Area: 529 sq. ft.
  • Empty Weight: 25,630 lbs.
  • Loaded Weight: 34,996 lbs.
  • Crew: 2

Performance

  • Power Plant: 2 × Pratt & Whitney J52-P8B turbojets
  • Range: 3,245 miles
  • Max. Speed: 648 mph (Mach 2.23)
  • Ceiling: 40,600 ft.

Armament

  • 5 hardpoints, 4 on wings, 1 on fuselage capable of carrying 18,000 lbs. of bombs or missiles

    A-6 Intruder - Background:

    The Grumman A-6 Intruder can trace its roots back to the Korean War. Following the success of dedicated ground-attack aircraft, such as the Douglas A-1 Skyraider, during that conflict, the US Navy prepared preliminary requirements for a new carrier-based attack aircraft in 1955. This was followed by the issuance of operational requirements, which included all-weather ability, and a request for proposals in 1956 and 1957 respectively. Responding to this request, several aircraft manufacturers, including Grumman, Boeing, Lockheed, Douglas, and North American, submitted designs. After assessing these proposals, the US Navy selected the bid prepared by Grumman. A veteran in working with the US Navy, Grumman had designed earlier aircraft such as the F4F Wildcat, F6F Hellcat, and F9F Panther.

    A-6 Intruder - Design & Development:

    Proceeding under the designation A2F-1, the development of the new aircraft was overseen by Lawrence Mead, Jr.

    who would later play a key role in the design of the F-14 Tomcat. Moving forward, Mead's team created an aircraft that utilized a rare side-by-side seating arrangement where the pilot sat on the left with the bombardier/navigator slightly below and to the right. This latter crewmember oversaw a sophisticated set of integrated avionics which provided the aircraft with its all-weather and low-level strike capabilities.

    To maintain these systems, Grumman created two levels of Basic Automated Checkout Equipment (BACE) systems to aid in diagnosing issues.

    A swept-wing, mid-monoplane, the A2F-1 utilized a large tail structure and possessed two engines. Powered by two Pratt & Whitney J52-P6 engines mounted along the fuselage, the prototypes featured nozzles that could rotate downward for shorter takeoffs and landings. Mead's team elected not to retain this feature in the production models. The aircraft proved capable of carrying an 18,000-lb. bomb load. On April 16, 1960, the prototype first took to the skies. Refined over the next two years, it received the designation A-6 Intruder in 1962. The first variation of the aircraft, the A-6A, entered service with VA-42 in February 1963 with other units obtaining the type in short order.

    A-6 Intruder - Variations:

    In 1967, with US Navy aircraft embroiled in the Vietnam War, the process began to convert several A-6As into A-6Bs which were intended to serve as defense suppression aircraft. This saw the removal of many of the aircraft's attack systems in favor of specialized equipment for employing anti-radiation missiles such as the AGM-45 Shrike and AGM-75 Standard.

    In 1970, a night-attack variant, the A-6C, was also developed which incorporated improved radar and ground sensors. In the early 1970s, the US Navy converted part of the Intruder fleet into KA-6Ds to fulfill a mission tanker need. This type saw extensive service over the next two decades and was often in short supply.

    Introduced in 1970, the A-6E proved the definitive variant of the attack Intruder. Employing the new Norden AN/APQ-148 multi-mode radar and AN/ASN-92 inertial navigation system, the A-6E also utilized the Carrier Aircraft Inertial Navigation System. Continually upgraded through the 1980s and 1990s, the A-6E later proved capable of carrying precision-guided weapons such as the AGM-84 Harpoon, AGM-65 Maverick, and AGM-88 HARM. In the 1980s, designers moved forward with the A-6F which would have seen the type receive new, more powerful General Electric F404 engines as well as a more advanced avionics suite.

    Approaching the US Navy with this upgrade, the service declined to move into production as it favored development of the A-12 Avenger II project. Proceeding in parallel with the career of the A-6 Intruder was the development of the EA-6 Prowler electronic warfare aircraft. Initially created for the US Marine Corps in 1963, the EA-6 used a modified version of the A-6 airframe and carried a crew of four. Enhanced versions of this aircraft remain in use as of 2013 though its role is being taken by the new EA-18G Growler which entered service in 2009. The EA-18G employs an altered F/A-18 Super Hornet airframe.

    A-6 Intruder - Operational History:

    Entering service in 1963, the A-6 Intruder was the US Navy and US Marine Corps' primary all-weather attack aircraft at the time of the Gulf of Tonkin Incident and US entry into the Vietnam War. Flying from American aircraft carriers off the coast, Intruders struck targets across North and South Vietnam for the duration of the conflict. It was supported in this role by US Air Force attack aircraft such as the Republic F-105 Thunderchief and modified McDonnell Douglas F-4 Phantom IIs. During the course of operations over Vietnam, a total of 84 A-6 Intruders were lost with the majority (56) downed by anti-aircraft artillery and other ground fire.

    The A-6 Intruder continued to serve in this role after Vietnam and one was lost during operations over Lebanon in 1983. Three years later, A-6s participated in the bombing of Libya following Colonel Muammar Gaddafi's support of terrorist activities. The A-6's final wartime missions came in 1991 during the Gulf War. Flying as part of Operation Desert Sword, US Navy and Marine Corps A-6s flew 4,700 combat sorties. These included a wide array of attack missions ranging from anti-aircraft suppression and ground support to destroying naval targets and conducting strategic bombing. In the course of the fighting, three A-6s were lost to enemy fire.

    With the conclusion of hostilities in Iraq, A-6s remained to help enforce the no-fly zone over that country.

    Other Intruder units conducted missions in support of US Marine Corps activities in Somalia in 1993 as well as Bosnia in 1994. Though the A-12 program had been cancelled due to cost issues, the Department of Defense moved to retire the A-6 in the mid-1990s. As an immediate successor was not in place, the attack role in carrier air groups was passed to LANTIRN-equipped (Low Altitude Navigation and Targeting Infrared for Night) F-14 squadrons. The attack role eventually was assigned to the F/A-18E/F Super Hornet. Though many experts in the Naval Aviation community questioned retiring the aircraft, the last Intruder departed active service on February 28, 1997. Recently refurbished and late-model production aircraft were placed in storage with Davis-Monthan Air Force Base's 309th Aerospace Maintenance and Regeneration Group.

    Selected Sources