The Harrier II is a family of second generation vertical/short takeoff and landing (V/STOL) jet aircraft of the late 20th century. They were developed from the earlier Hawker-Siddeley Harriers, are primarily used for light attack or multi-role tasks, and are almost all operated from small aircraft carriers. Versions of it are used primarily by NATO countries, and also by India. This includes:

The Royal Air Force and Fleet Air Arm of the United Kingdom under a number of variants and versions starting in the late 1980s, including the GR.7, T.10, FRS.1, FA.2 and T.4 versions. (see RAF Harrier II, BAE Sea Harrier )

United States Marine Corps as the McDonnell Douglas AV-8B and TAV-8B starting in 1985.

The Spanish Naval air wing (Arma Aerea De La Armada) as the AV-8B+, AV8-B and a TAV-8S.

The Italian Navy air wing (Aviazione per la Marina Militare) as the AV-8B and TAV-8.

The Indian Navy as the FRS51 and T60.

The Harrier II is also notable in history as an example of U.S.-U.K cooperation and of Cold War defense achievements. Of note is the U.S aid funding early development under the Mutual Weapons Development Program (MWDP) and the salvaging of what was left of the AV-8A Advanced Harrier Program by McDonnell Douglas, making the second-generation family possible.

The AV-8B had its direct origins in a Joint U.S.-British project (Hawker-Siddeley and McDonnell Douglas Aircraft) for a much-improved Harrier aircraft, to be the AV-16A Advanced Harrier program. However cost over-runs in engine development on the part of Rolls Royce and in the aircraft development caused the British to pull out of the program. Interest remained in the U.S. so a less ambitious, though still expensive project was undertaken by McDonnell on their own catered to U.S. needs. Using things learned from AV-16A development, though dropping some things such as further Pegasus development, the development work continued leading the AV-8B for the U.S. Marine Corps. The aircraft was centered on the Marine's needs, light ground attack and was focused on payload and range as opposed to speed. In the late 1970's the British re-entered development of their own second generation Harrier based on the U.S. design leading eventually to the GR.5, which had somewhat different performance goals.

Armament

Detachable fuselage strakes can be replaced with pods for one GAU-12U "Equalizer" 25 mm cannon (left pod) and 300 rounds of ammunition (right pod) 7 pylons for a maximum of 13,200 lb (STOL) of stores, including: Iron bombs, cluster bombs, napalm canisters, laser-guided bombs, AGM-65 Maverick missiles, and up to four AIM-9 Sidewinder or similar-sized infrared-guided missiles. AV-8B+ variants can carry up to four AIM-120 AMRAAM missiles.