A-6F and A-6G

An advanced A-6F Intruder II was proposed in the mid-1980s that would have replaced the Intruder's elderly Pratt & Whitney J52 turbojets with non-afterburning versions of the General Electric F404 turbofan used in the F/A-18 Hornet, providing substantial improvements in both power and fuel economy. The A-6F would have had totally new avionics, including a Norden AN/APQ-173 synthetic aperture radar and multi-function cockpit displays � the APQ-173 would have given the Intruder air-to-air capacity with provision for the AIM-120 AMRAAM. Two additional wing pylons were added, for a total of seven stations.

Although five development aircraft were built, the Navy ultimately chose not to authorize the A-6F, preferring to concentrate on the A-12 Avenger II. This left the service in a quandary when the A-12 was cancelled in 1991.

Grumman proposed a cheaper alternative in the A-6G, which had most of the A-6F's advanced electronics, but retained the existing engines. This, too, was cancelled.

Electronic warfare versions:

An electronic warfare/ECM version of the Intruder was developed early in the aircraft's life for the USMC, which needed a new ECM platform to replace its elderly F3D-2Q Skyknights. An EW version of the Intruder, initially designated A2F-1Q and subsequently redesignated EA-6A, first flew on 26 April 1963. It had a Bunker-Ramo AN/ALQ-86 ECM suite, with most electronics contained on the walnut-shaped pod atop the vertical fin. They were theoretically capable of firing the AGM-45 Shrike anti-radiation missile, although they were apparently not used in that role.

Only 28 EA-6As were built (two prototypes, 15 new-build, and 11 conversions from A-6As), serving with Marine Corps squadrons in Vietnam. It was phased out of front-line service in the mid-1970s, remaining in use in reserve units with the USMC and then the US Navy primarily for training purposes. The last had been retired completely by 1993.

A much more highly specialized derivative of the Intruder was the EA-6B Prowler, a 'stretched' airframe with two additional systems operators, and more comprehensive systems for the electronic warfare and SEAD roles. In total, 170 were produced. The Prowler remains in service as of 2008, replacing the Air Force EF-111 Raven aka "Spark Vark" when the DOD decided to let the Navy handle all electronic warfare missions. It is scheduled to be replaced by the EA-18G Growler Super Hornet variant.

Prototypes/test aircraft: NA-6A The redesignation of three YA-6As and three A-6As. The six aircraft were modified for special tests YEA-6A One YA-6A aircraft was converted into the EA-6A prototype. YEA-6B The designation of two EA-6B prototypes, which were modified for special test purposes. NEA-6A One EA-6A aircraft was modified for special test purposes.