Boeing (BAe Systems / McDonnell Douglas) AV-8B Harrier II V/STOL Strike Fighter Aircraft
Authored By Dan Alex; Content ©www.MilitaryFactory.com
Boeing (BAe Systems / McDonnell Douglas) AV-8B Harrier II
The AV-8B Harrier II became a vastly improved and highly developed form of the original Harrier family line.
While the original Hawker Siddeley Harrier proved revolutionary for its time, and the follow-up BAe Systems Sea Harrier bettered the type's original design with the inclusion of radar and improvements in out-of-the-cockpit visibility, vertical control and armament, the aircraft still maintained an origin firmly entrenched in the 1960s. By the middle of the 1970s, it became clear that the aircraft had all but met its potential and limitations were apparent - particularly in range, avionics and payload capacity. What essentially began and ended as a joint venture between British and American aeronautic firms (the British bailed early, then rejoined later on) produced the ultimate Harrier form in the "AV-8B Harrier II". The AV-8B (and under its British designation as the Harrier GR) saw combat action in Iraq, over Kosovo and now over Afghanistan and continues to be the Harrier version of choice for the USMC and RAF/RN.
Breakdown of the Harrier Family Tree
The Harrier family line consists of four major versions composed of the Hawker Siddeley Harrier, the British Aerospace (BAe) Sea Harrier, the Boeing/BAe AV-8B Harrier II and the BAe Systems/Boeing Harrier II. Confusing at first, each model does differentiate from the other in some distinct way. The initial production model and beginning of the Harrier lineage was the Hawker Siddeley Harrier. The Sea Harrier (as the name implies) became the dedicated navalized version of the base Harrier and utilized for air-defense as a primary role and ground strike as secondary. The Sea Harrier also made use of the powerful Blue Fox radar and was a direct development of the land-based RAF Harrier GR.3. The Boeing/BAe AV-8B Harrier II became a "second generation" Harrier and is a highly-modified version of the original Harrier for use by the USMC while the BAe Harrier II is a British-modified strike version of the USMC Harrier II.
Hawker Aircraft Limited was absorbed by Hawker Siddeley Group in the late 1950s and became British Aerospace (BAe) in 1977. British Aerospace became BAe Systems in 1999 after its purchase of Marconi Electronic Systems.
This article covers the second generation McDonnell Douglas Corporation (MDC) / BAe Systems AV-8B and Harrier GR types. Other models are reviewed elsewhere on this site under their respective manufacturers.
Even before the Sea Harrier was in development, the British and Americans were entertaining an option for an Advanced Harrier concept. Bristol has developed and successfully tested the Pegasus 15 with its 24,500lbf output rating. This new engine was noticeably larger in diameter than the existing family of Pegasus turbofans driving the existing (and original) Hawker Siddeley Harrier. The thinking now was that a whole new airframe could be designed around the Pegasus 15 to take on its potential capabilities. As such, a new joint venture was begun in 1972.
An original agreement between the British and American governments made for acquisition of foreign-made AV-8 Harriers concluded in a 15-year agreement in which American-based McDonnell Douglas could lay claim to local production of the aircraft (this never took place) as well as take on any future derivative development. Seeing it that the RAF was already looking ahead to the original Harrier's replacement (as were the USMC) and the US Navy was looking to replace their aging fleet of Douglas A-4 Skyhawks, the endeavor was a sound one to undertake. The Advanced Harrier project gained the unofficial designation of AV-16 while Hawker Siddeley assigned the designation of P.1184 to it.
The P.1184 would be a highly-modified version of the original Harrier design. To go along with the new Pegasus 15 series engine was a new wider fuselage. More importantly, a new "supercritical" wing, The wing was categorized as such in that it featured a specially-designed airfoil that worked to delay the onset of wave drag while at transonic speeds. Like the Harrier before it, the AV-16 would also be of a subsonic aircraft design. The wing would also increase external weapons carrying capacity to six underwing hardpoints while also be able to store more internal fuel thusly increasing range. A second study, becoming the AV-16-S6/P.1185, was developed as a high-altitude supersonic derivative.
Externally, the AV-16-S6 would appear as a much streamlined and longer version of the Sea Harrier complete with bubble canopy and single vertical tail fin. The wider fuselage would fit two large side intakes feeding the new Pegasus 15 engine. The outboard riggers would be set behind the innermost underwing hardpoint but the general Harrier layout would be retained.
In March of 1975, citing "insufficient common ground" in the program and (perhaps the most likely culprit) ballooning costs in a shrinking English defense environment, Hawker Siddeley decided to remove themselves from the project altogether. The Pegasus engine was far from being cleared for operational use and further money and time would be needed to make that happen. Couple that with the work needed to design, develop and test a new airframe amongst the diminishing defense budget in Britain and the Hawker Siddeley move becomes understandable. Unable to go at it alone, the United States equally abandoned the project and that was that. Hawker continued some work on finding a "super Harrier" solution but these all came to naught.
McDonnell Douglas, too, worked along with their own Harrier research and came to the conclusion that new, carbon fiber supercritical wing with larger surface area was the answer. Though larger than any other carbon fiber wing of the time, the new assembly would actually weigh less than the original all-metal wing. The original Harrier design was furthered by implementing larger air intakes, slotted flaps, additional air-lift devices and a retractable lateral fence to assist in capturing a cushion of air beneath the aircraft while in hover. The wings had their sweep revised by 4-degrees and were extended to promote better lateral control and cruising. Rolling was improved (as was lateral control by having the underwing-mounted thrusters set further apart. The wider wingspan also promoted the use of an additional underwing hardpoint and greater payloads. The outrigger landing legs were also brought in to provide for a more stable track during ground operation. The forward fuselage was inevitably revised with more composite construction and fitted with a higher cockpit and better canopy bubble canopy while the rear fuselage was lengthened. The vector thrust nozzles were lengthened.
The new changes in the Harrier line brought about by the Americans were now approved for development by the US government on July 27th, 1976. The aircraft would take on the designation of AV-8B and the first such developmental model incorporating the new changes was a modified non-flying AV-8A. Two flyable AV-8As were later converted (though without the fuselage changes) and garnered the development designation of YAB-8B and flown in 1979. Though proving slower than the original Harrier, the design was nonetheless a promising first step and completely fit into the needs for the USMC at the time. 1979 also saw US commitment to the "Harrier II" project in full with the first production order for 336 aircraft placed in the queue with McDonnell Douglas.
By now, the British had come to their senses and BAe was back in talks with McDonnell Douglas. As a benefit, the Americans did end up spending their own money in the development of the Harrier II and all the British would have to do is spend money on acquisition instead of research, development, testing AND manufacture. The major drawback to their situation lay in Harrier II's "as is" state which did not allow for much in the way of major modifications to suit British combat needs.
While the original Harrier's development/production saw the British take a majority role in the program while the Americans were given a minor stake in the project, roles were reversed with the production of the Harrier II. McDonnell Douglas would be responsible for up to 60% of the airframe construction while BAe would retain only 40%. Additionally, however, all American AV-8Bs would have final assembly handled at the McDonnell Douglas plant in St Louis, Missouri while all British aircraft would be have their final assembly handled at British Aerospace facility in Dunsford. Engine manufacturing would also be undertaken by a joint venture between Pratt & Whitney in America and Rolls-Royce in Britain.
The first pre-production Harrier II became airborne on November 5th, 1981. Three more such Harrier IIs followed with the final one fitting a common 25mm General Electric GAU-12/U multi-barrel Gatling-type cannon for weapons trials. The original Harrier fitted a pair of 30mm ADEN cannons in underfuselage pod fairings but these proved too unique for the American inventory as no other American aircraft fitted the weapon type. While not making use of the ADEN cannon set up, McDonnell Douglas kept the pod fairings for their aerodynamic value and instead used the portside pod fairing for the 25mm cannon and the starboard side pod fairing for 300 rounds of 25mm ammunition. The second YAV-8B prototype went airborne on February 19th, 1979, and initially proved successful but was eventually lost to an engine flame-out incident on November 15th of that year - the pilot ejecting safely.
The cockpit was wholly revised as a larger workspace with ergonomics an important consideration. The entire cockpit position was raised 12 full inches higher than previous and the two-piece canopy was given a higher apex for more headroom and better vision out of the cockpit. The navigation and avionics suites were both addressed with more powerful and capable systems although these systems would differ between the American and British aircraft as expected. HOTAS (Hands-On Throttle and Stick) was integrated as was a more effective HUD (Heads-Up Display). Large Multi-Function Displays (MFDs) as found on the F/A-18 Hornet were utilized in the new American development while the bombing system of the Douglas A-4 Skyhawk was implemented.
The ALR-67 radar warning receiver was added as were two ALE-29 chaff/flare dispensers were affixed to the underside of the fuselage just aft of the speedbrake. Two ALE-39 dispensers were also fitted to the upper sides of the rear fuselage, greatly increasing the Harrier IIs survivability. Additionally, the centerline hardpoint could now field the ALQ-164(V) countermeasures pod. Later, the AAR-44(V) was fitted to the tail stinger to warn of incoming enemy missiles from the rear.
The first dozen AV-8Bs were fitted with the F402-RR-404A turbofan engine while a newer F402-RR-406A (similar to the Pegasus Mk 105) series became the eventual mainstay of the Harrier II line. The Mark 105 engine had its roots in a Rolls-Royce venture taking place in 1980 and first test-flown on a Harrier GR.Mk 3 airframe beginning in 1982. Despite the use of the same powerplant in the new Harrier, the aircraft could still yield a greater payload and marked an impressive 70% improvement to hauling capabilities. Internal fuel stores were addressed and improved range by 50%. Along with these benefits came about a 60% reduction in maintenance hours required to keep the bird aloft.
The first AV-8B was flown on August 29th, 1983 and officially handed over to Training Squadron VMAT-203 at Cherry Point, North Carolina on January 12th, 1984. The first operational squadron became VMA-331 with numbers finally reaching 20 aircraft in March of 1987. The new systems proved more than the original AV-8A pilots could handle so a production order of eight AV-8Bs was cut in favor of developing the all-important two-seat TAV-8B Harrier II. The TAV-8B arrived in Marine hands on July 24th, 1987.
Differences between the production AV-8B and the TAV-8B were subtle. The TAV-8B naturally needed a larger cockpit to seat two pilots and was therefore afforded a lengthened fuselage. This was offset by a longer tail stinger and a taller vertical tail fin. Unlike the British trainers to come, the TAV-8B did not retain any of her combat capabilities and was a true trainer at heart fitting only a pair of underwing hardpoints for fuel and practice ordnance.
The second operational USMC squadron became the VMA-231 in July of 1986, with operating strength reached at 15 AV-8Bs. Before the end of 1986, squadron VMA-457 was next brought online. These two squadrons were then followed into service by the VMA-513, which was incidentally the last operator of the original first-generation AV-8A Harriers.
The British took the American-modified AV-8B Harrier II and initially produced a pair of GR.Mk 5s that were fitted the Pegasus Mk 105 engine as well as British-based avionics, radio, countermeasures and applicable weaponry. First flight was achieved on April 23rd, 1985 and the first GR.Mk 5 went operational in July of 1987.
When all was said and done, the Harrier had evolved into a much more special combat platform. No longer tied to the notion of basic close-support sorties as its only forte, the Harrier II sprouted combat capabilities that made it a premiere ground strike aircraft with unparalleled attack helicopter-like capabilities no other conventional aircraft could match. The new Harrier could also defend itself through the use of internal cannons or externally-mounted short-range air-to-air missiles when armed as such.
McDonnell Douglas Corporation was absorbed as a subsidiary of the Boeing Company while BAe became BAe Systems. Each respective corporation now manages the current and future line of AV-8B Harrier IIs and Harrier GRs in service.
To the casual observer, it could be argued that the AV-8B changed little from her first generation Harrier/Sea Harrier days. However, closer study would quickly reveal the larger raised cockpit - a key identifiable feature of the newer Harrier - as well as a the larger-area wing and its additional hardpoints. The wings retain their noticeable anhedral and, despite being all-new, the nose cone assembly kept much the same shape as that of the Sea Harrier before it. The intakes are noticeably larger on the AV-8B and straddle either side of the cockpit. The fuselage tapers off at the rear to which a single vertical tail fin is affixed. The tail sports a pair of horizontal stabilizers, also with anhedral. The undercarriage remains nearly the same as in the early Harrier forms and is made up of a single-wheeled nose leg and double-wheeled main landing gear leg. The two outrigger legs that were originally positioned at the wingtips are now brought inwards to help provide for a better ground track. The AV-8B is fitted with a UPC/Stencel type 10B series ejection seat. The in-flight refueling probe is tucked away along the upper portion of the portside intake opening.
Avionics of American Harrier II consisted of a Collins RT-1250A/ARC U/UHF radio system, a Bendix RT-1157/APX-100 IFF system and a Litton AN/ASN-130A INS (Inertial Navigation System). Once the APG-65 radars became available to USMC McDonnell Douglas F/A-18 Hornets, several Harrier IIs also fitted the device, becoming known as "Harrier II Plus". The first Harrier II Plus entered service with the VMA-542 in 1993 and, by 2003, all other AV-8Bs in USMC service were also duly upgraded. It is expected that the Harrier II Plus models could very well last up until 2025.
The American AV-8B fields a standard armament suite consisting of a single 20mm General Electric GE GAU-12A "Equalizer" five-barrel Gatling-type gun inside of a portside underfuselage pod fairing. Approximately 300 rounds of ammunition are carried in a similar starboard side fairing. The British GR version originally fielded 2 x 30mm ADEN cannons in like- pod fairings under the fuselage.
The American Harrier II makes use of 7 hardpoints (6 underwing; 1 centerline) which can max out to 13,200lbs of ordnance. Options include the AGM-65 Maverick air-to-surface missile, the AGM-84 Harpoon anti-ship missile, up to 4 x AIM-9 Sidewinder short-range or AIM-120 AMRAAM medium-range air-to-air missiles, conventional drop bombs, laser-guided bombs, cluster bombs, napalm and Joint Direct Attack Munitions - the latter making lethal use of GPS guidance. Targeting and reconnaissance pods, as well as up to 4 x auxiliary fuel tanks, can replace armament.
External ordnance options for the Harrier GR are primarily made up of LAU-5003, BL775 and Matra rocket pods. Additional options include use of the American-made AGM-65 Maverick air-to-surface missile, the MBDA Brimstone anti-tank missile, CBU-87 cluster bombs and conventional or the Paveway family of laser-guided bombs (LGB) across 9 hardpoints. AIM-9 Sidewinder short-range air-to-air missiles are fielded in self-defense as GRs lack internal cannons. External hardpoints can also make way for auxiliary drop tanks for improved ranges and loitering times or reconnaissance pods as needed. Later GR models can self-designate their targets.
The YAV-8B designation was afforded to the two aforementioned developmental prototypes that made use of existing USMC AV-8A airframes (there was also a USMC C-model in the original Harrier crop). Consequently, production models followed with the "AV-8B" designation despite the Harrier II being essentially a "like-new" aircraft in many ways.
The AV-8B was the initial USMC production Harrier II model and was categorized as a daytime strike fighter. These served for a time before being replaced or retired altogether by the newer AV-8B variants. The Italian Navy was a recipient of similar AV-8Bs and it is believed that 15 of these are still in service as of early 2009 with the Gruppo Aerei Imbarcati. Italy took an initial batch of nine aircraft (including one trainer) through deliveries beginning in 1994.
The AV-8B(NA) "Night Attack" Harrier II variant (originally known as the AV-8D) began development in 1984 and implemented NAVFLIR (Navigation Forward-Looking Infrared camera consisting of a GEC-Marconi FLIR system mounted in the nose) for night operations. Additionally, GEC Cat's Eyes night vision goggles were provided to the pilot as well as a revised cockpit with new color MFDs, a wider field-of-view HUDs display, a color CRT digital moving map and complete "heads-down" operation capability. The FLIR is mounted on the top of the nose assembly which helps the casual observer in identification of the Harrier type in photography. The Night Attack Harrier II also sports four Tracor ALE-39 countermeasures dispensers along the top of the rear fuselage in addition to the two ALE-39 dispensers along the lower rear of the fuselage. The AV-8B(NA) also fields an uprated version of the Rolls-Royce Pegasus 11-61 (F402-RR-408) vectored-thrust turbofan engine. First flight of a modified AV-8B in night attack from was on June 26th, 1987. Deliveries to the USMC began in September of 1989 to VMA-214 at Yuma. Follow-up units based out of Yuma received their Night Attack forms by the end of 1992.
The AV-8B Harrier II+ (or "Harrier II Plus", also originally known as the AV-8E) incorporated the additions made in the Night Attack model but added the Hughes APG-65 pulse-Doppler radar system as found on the McDonnell Douglas F/A-18 Hornet (with the exception of the Sea Harrier, no previous Harrier model was fielded with a radar system) the "100%" LERX (Leading Edge Root Extension) and Beyond Visual Range (BVR) capability. Since the F/A-18 Hornet was due to be upgraded with the APG-73 series radars, the APG-65 would be in good supply. Considering cost measures for the time, the APG-65 was the economical choice despite the fact that the British Blue Vixen system was probably the right choice.
The United States, Britain, Spain and Italy all played a role in the new type's development. The Harrier II+ is now the primary USMC model and (as of this writing) is fielded with VMA-211, VMA-214, VMA-223, VMA-231, VMA-311, VMA-513, VMA-542, VMAT-203, VX-31 and VX-9. Additionally, the Harrier II+ was delivered to the Spanish and Italian Navies complete with AIM-120 AMRAAM capability. Performance specs for this improved variant include a reported top speed of 662 miles per hour, a range of 1,400 miles and a rate-of-climb equal to 14,700 feet per minute. First flight of the new Harrier II occurred on September 22nd, 1992. Deliveries followed to USMC units at Cherry Point.
The TAV-8B Harrier II became the tandem twin-seat trainer models of the AV-8B line. These fitted a second separate cockpit in a stepped arrangement just aft of the primary cockpit and provided redundant flight controls for the instructor. However, only two underwing hardpoints were provided for in these special Harrier models.
EAV-8B "Matador II" was the designation reserved for Spanish export Harrier II's. These were fielded by the Spanish Navy as part of their 09th Squadron. At least 13 AV-8B Harrier II Plus aircraft are still believed to be in service as of early 2009. Spanish Matador IIs began delivery in October of 1987.
British Harrier IIs
British Harrier IIs are known by their formal designation of BAe Systems/Boeing Harrier II (McDonnell Douglas Corporation had become a subsidiary of Boeing) and cover the GR.Mk 5, GR. Mk 7 and GR.Mk 9 production series. Though initially fielded by the RAF, the Royal Navy gave up use of their Sea Harriers and made use of GRs beginning in 2006 (first the GR.Mk 7 then the follow-up GR.Mk 9).
The GR.Mk 5 was the first second-generation Harrier to become available for the RAF. The Mk 5 featured British-inspired modifications that differentiated this model from the American AV-8B to a good degree and became the standard RAF Harrier since inception with some 40 examples produced. These were followed by the GR.Mk 5A in 21 examples and incorporated new features (such as FLIR) that would become standardized in the upcoming GR.Mk 7. First flight of the new mark was on November 20th, 1989.
The GR.Mk 7 was an improved form of the GR.Mk 5 and is the equivalent of the night-fighting Harrier II. First delivery was in May of 1990 with operational status was achieved in August of 1995. GR.Mk 7's implemented the same GEC Marconi FLIR system for night operations as the USMC AV-8B "Night Harrier. Unlike the USMC, the RAF GR.Mk 7 fields the Ferranti Night-Owl night vision goggles. Like the USMC, this night-capable Harrier became the new British standard Harrier mount. Countermeasures consist of the Marconi Zeus ECM (Electronic CounterMeasure) integrated into an automatic-reaction countermeasures chaff/flare system that selects the appropriate defense based on missile tracking. The GR.Mk 7 was used concurrently between the RAF and Royal Navy with at-sea deployments beginning in 1997. The new variant reported performance statistics of 662 miles per hour in top speed, 2,015 miles of ferry range, a 50,000 foot service ceiling and a rate-of-climb equal to 14,715 feet per minute. GR.Mk 7s will eventually be upgraded to the GR.Mk 9 standard.
The GR.Mk 7A was an upgrade program of existing GR.Mk 7s to a new GR.Mk 9 standard. Theses GR.Mk 7As were fitted with a more powerful Rolls-Royce Pegasus Mk 107 series vectored-thrust turbofan engine. Weapon options have also been dramatically expanded. Some 40 upgraded GR.Mk 7s made up the GR.Mk 7A variant line.
As it stands, the GR.Mk 9 is the ultimate British Harrier II Mark standard and features upgraded weapons and avionics suites first implemented in the GR.Mk 7. The new Harrier has "smart weapons" capability which can utilized GPS for accurate targeting and engagement. Additionally, the aircraft supports the latest line of AGM-65 Maverick air-to-surface family of missiles, Brimstone anti-tank missiles and Paveway laser-guided bombs as well as rocket pods and conventional drop bombs as needed. The engine remains the Pegasus Mark 105 series but as more GR.Mk 9s are fitted with the newer Pegasus Mk 107 (of the GR.Mk 7As) they will take on the designation of GR.Mk 9A themselves.
The T.Mk 10 is the British designation of the base two-seat trainer that covers the systems of the GR.Mk 5 fighter. T.Mk 10s were a bit different from their American TAV-8Bs in that they included eight underwing hardpoints instead of two, retaining their full combat capabilities as well as night-attack systems. Though these replaced the outdated T.Mk 4s of the original Harrier set, the T.Mk 12 now replaces the T.Mk 10 in turn. The T.Mk 12 features the upgrades found on the GR.Mk 7 and GR.Mk 9 variants as well as student/instructor tandem seating with dual controls.
BAe Systems Harriers current serve only with the Royal Air Force and Fleet Air Arm as part of the Nos 1, 3, IV and 20 Squadrons as well as the Naval Strike Wing of the FAA.
Harrier IIs in the Gulf
An oft-forgotten fact is that the AV-8B Harrier II became the first USMC aircraft to be deployed in the Gulf in preparation for Operation Desert Storm. In 1991, Iraqi dictator Saddam Hussein had invaded the smaller, oil-rich country with what was then the fourth largest army in the world. Five of the total eight Marine Harrier squadrons came to the region and war proved all but inevitable.
Once the opening rounds of Desert Storm were over, this comprised of off-shore cruise missile strikes and F-117 stealth fighter attacks, the coalition of NATO nations unleashed hell on the occupiers in Kuwait. AB-8Bs were flown against Iraqi ground targets using rockets, air-to-surface missiles and bombs or various types (napalm, cluster). Sidewinder air-to-air missiles were utilized early on in a defensive role but this need all but dissipated with the death of the Iraqi air force meaning that the AV-8Bs could utilize their pylons for more offensive stores. At the cost of five AV-8Bs, the Harrier II flew in 3,380 sorties and totaled some 4,112 hours in 42 days. By war's end, an estimated six million pounds of ordnance had been delivered by the Harrier IIs against Iraqi targets making it one of the more important battlefield elements of the short-lived conflict.
The Future of the Av-8B Harrier II/Harrier II GR
Though still a serviceable machine, the Harrier II is expected to be replaced in time (possibly beginning in 2018) by the new-generation Rolls-Royce-powered Lockheed F-35 Lightning II - the end-product of the Joint Strike Fighter development program. Available in three options - an A-, B- and C- model - the F-35B (and, its integrated vertical flight system) will become the new Short Take-Off and Vertical Landing (STOVL) mount of the United States and United Kingdom. Other participants in the F-35 program include Turkey, Australia, Israel and the Netherlands.
Production of all new-build Harrier IIs ceased in 1997 though some were receiving new-build fuselages as recently as 2004.
As of 2010, all RAF Harrier GR.Mk 9 ground attack aircraft were mothbolled in a cost-cutting initiative.