Due to old forums shutting down (albeit not that soon) and since I made discussion topics about several jets there, it’s time to make a new discussion topic here.
But before this wall of text begins, I would just like to thank @BearHasLanded for posting Legacy Hornet topic.
McDonnell Douglas AV-8B Harrier II
AV-8B Plus and AV-8B (NA) in formation after refueling - Note the radome on AV-8B Plus (Foreground) which houses APG-65 radar
History:
Spoiler
Prelude: The AV-8A and AV-8C
AV-8A/C Harrier taking off from the deck of USS Nassau amphibious assault ship (LHA-4)
The AV-8A Harrier, used by the Marines, was a based on Harrier GR MK.3. Under the procurement restrictions imposed upon the USMC purchase of the Harrier, the machine was bought as an “in production, off the shelf” aircraft which required little or no change in order to go into service. Differences between USMC AV-8A and British GR MK.3 were few; a weight-on-wheel armament switch, take-off and landing checklist in cockpit, USN radio equipment with tactical VHF antenna mounted on the mid-upper fuselage, and permanently attached wing pylons for Sidewinder missiles. Flight testing of all USN ordnance was conducted in the UK and was found to be satisfactory.
Ordered with the MK.103 engine, the first ten AV-8As were in fact delivered (beginning February 1971) with the less powerful MK.102. However, these machines were subsequently retrofitted with the MK.103 engine. Requiring a simple and more easily maintained navigational /weapons systems, the FE 541 inertial nav-attack system was replaced by the simpler I/WAC (Interface/Weapon Aiming Computer) known as the Baseline System. From the 60th production aircraft, the AV-8A was delivered with a redesigned cockpit, and from the 90th production machine it was featured with US manufactured Stencil S111S-3 ejection seat replacing the standard British Martin Baker seat.
The Marine Corps has found the Harrier to be the ideal close support ground attack fighter and the fact that their purchase was slowly spread over five years says more about the financial string pullers than about corps enthusiasm for their Harrier. Given the Harrier’s unique ability to operate from the deck of assault ships as well as its ability to stay close to the ground forces by operating from just behind the front lines or from rudimentary bases within a beachhead, the AV-8A Harrier was in use by USMC for some time, only to be replaced by superior AV-8B Harrier II.
Always innovative the Marine Corps has written a new page in the air-to-air combat tactics manual by using the vectored thrust, not just for vertical take-off and landings but also during forward flight as well. Termed Vectoring In Forward Flight (VIFF) or VIFFing as the pilots refer to it, dates back to the first flight trials by Miller and Baker when Miller hit the nozzle selector, causing Baker to overshoot him, VIFFing provides an extraordinary rate of deceleration during level flight, and turning the nozzles downward during a rolling turn provides a very tight turn.
With AV-8B still in works, it was decided to upgrade existing AV-8As with LIDs (Lift Improvement Devices) developed for the AV-8B. Under the designation AV-8C and beginning in 1979, the first machine to be retrofitted with enlarged strakes and retractable air dam was BuNo 158384, the very first production AV-8A. Besides LIDs, radar warning antennas were installed in the wing tips and tail cone and chaff/flare dispensers were added to the rear fuselage.
AV-16A and YAV-8B Harrier II
Spoiler
The Harrier that wasn’t - AV-16/AV-8X
By 1975, the Harrier GR. Mk1 and the US Marines’ AV-8A were looking decidedly tired, their primitive avionics severely limiting operational capability. The addition of Ferranti LRMTS and a radar warning receiver to produce the GR. Mk3 was no solution to the underlying problems of lack of sophistication, range and payload capability. In the US, some people claimed that the AV-8A could not carry “a pack of cigarettes the lengths of a football field.” Using STOL techniques, the AV-8A could tote 1,500lb (681kg) over a 380nm (703km) radius, with a 1,200ft (365m) take off run - only 70nm (130km) short of the A-4’s normal radius, but with less than half of the Skyhawk’s 4,000lb (1814kg) payload. The Skyhawk did require much more of an airfield, however. Comparisons with the lightweight Skyhawk revealed that what was actually needed was a VTOL or STOVL strike fighter with the payload and range of aircraft like the F-105 or A-7, or perhaps even the F-111. The era of fast-jet CAS was coming to an end, and future jet fighter-bombers would need to strike further behind the front line.
Hawker Siddeley had examined a plethora of advanced Harrier designs, most notably the P.1184 “Super Harrier” with increased thrust and wing area giving improved payload capability. McDonnell Douglas had explored an advanced Harrier for the US Navy under the designation AV-8C (later reapplied to a simple SLEP-type upgrade to USMC AV-8As). Finally, in 1973, Hawker Siddeley and McDonnel Douglas teamed to examine Harrier derivatives, primarily to meet the US Navy Air Systems Command HIPAAS (High Performance Attack Aircraft System) requirement for a new STOVL or VTOL strike fighter. The aircraft was also intended to fulfil and RAF requirement for a Harrier replacement, a US Marine requirement for a Skyhawk and first-generation Harrier replacement, and to serve aboard the Royal Navy’s new through-deck cruises and the US Navy’s projected Sea Control Ships. A Joint Management Board was established in 1972, with co-chairmen, project managers, financial and engine specialists from both countries. A 26-volume, jointly financed, eight-month project definition phase began on 12 April 1973 and was presented to the two governments on 13 December 1973. A Phase I specification was set out in 1974.
In 1969 McDonnell Douglas had been granted a license to manufacture the Harrier in the United States when the USMC placed its first order for the aircraft, and in 1971 Pratt & Whitney received a similar license for production of the Pegasus engine. In fact, the USMC’s 112 AV-8As and eight TAV-8As were all built at Kingston and were merely assembled by McDonnell Douglas. Although the option of building the Harriers in US was not exercised, the same agreement had provided for collaboration between Hawker Siddeley and McDonnell Douglas in future V/STOL and Harrier developments.
The aim of study was to produce a minimum-change, minimum-cost derivative of the harrier, taking advantage of the new 24,500-lb (108,99kN) Pegasus 15 engine and a new advanced wing design to produce what became known as the AV-16A Advanced Harrier. The unofficial AV-16A designation was applied to indicate the program’s objectives, which were to develop a Harrier with twice the payload/range capability. Specifically, the partners sought a VTO gross weight of 21,500lb (9752kg), or 25,000lb (11340kg) with a 320ft (97m) deck run, with a VTO payload of 2,000lb (907kg) over a 300nm (555km) radius, or 4,000lb (1814kg) over the same radius after a short take-off (STO).
The new aircraft was also known as the AV-8X. It would have a wider fuselage to accommodate the new engine, with its increased diameter fan (2 3/4in; 7cm larger), bigger intakes, a raised cockpit, strengthened undercarriage and new avionics. Although the Pegasus engine’s huge fan and “four-poster” nozzle configuration gave it a huge frontal area, factions in the US and the UK continued to press for a supersonic Harrier, although the aircraft’s inherently large frontal cross-section made such a development difficult, if not unlikely. A supersonic version, known variously as the AV-16S-6 or P.1185, was drawn up at much the same time as the AV-8X, incorporating Plenum Chamber Burning and relatively minor airframe improvements. An engine demonstrator using only the fan of the proposed Pegasus 15 had run at 24,900lb (110,74kN) in 1972, revealing that increased thrust, was quite possible. Similar McDonnell Douglas and Hawker Siddeley wing designs were evaluated and tunnel tested for the new design. Both proved to have superior drag and lift co-efficient characteristics to the original Harrier wing, despite their lower sweep, wider-span, extra hardpoints and thicker skins.
The AV-16A was finally halted in 1975, when the British government pulled out of the project, ostensibly because there was insufficient common grounds between the USMC, USN and RAF requirements, but also because the Pegasus 15 engine promised to be too expensive to develop, requiring, as it did, a new high-pressure section and an estimated $250 million (or even $500 million) R&D program. The overall costs of the AV-16A program were estimated at $31 billion or more, and this was simply too much for politicians in both countries to bear. It was a bad time for any advanced military program, with oil crisis in full flow, and with massive need for pubic expenditure cuts.
Attempt number 2 - YAV-8B
YAV-8B prototype taking off from specially built ramp
McDonnell Douglas continued to work on an advanced Harrier, although it, the AV-8A Plus (later AV-8B), was less ambitious than the AV-16 - to the delight of the US Marines, who wanted the Harrier to be kept simple, serviceable and survivable. The US Navy turned away from the project altogether, looking instead to the Rockwell XFV-12. Powered by Pegasus Mk 105 (derived from the Sea Harrier’s Mk 104, with a Digital Engine Control System), the new Harrier II combined the raised cockpit of AV-16 (itself developed from the raised Sea Harrier cockpit) with the McDonnell Douglas-designed, increased-span, increased-area, supercritical wing, of mainly composite construction, albeit with metal flaps, leading edges, pylon and outrigger attachment points. It was the largest single airframe component ever manufactured in epoxy resin composited and promised to be corrosion-proof, fatigue resistant and 400% stronger than an equivalent alloy wing. It demanded new construction techniques, in which laminated sheets were heated to 500°F (260°C) in an autoclave, under 200psi (1379kPa) pressure. The new wing was fitted with massive single-slotted positive circulation flaps, which lowered to 61° and added 7,600lb (3447kg) to STO lift.
The new wing had a 4° reduction in a sweepback but had increased span and a higher thickness/chord ratio, going from 8.5% to 10%. This thicker wing provided increased internal fuel tankage, equivalent to 30 minutes more of on-station time. Portions of upper wing skin were detachable for servicing, but the whole lower skin was fixed. It was 330lb (150kg) lighter than an equivalent metal wing.
The new Pegasus engine for the AV-8B was developed from 1980 by Rolls-Royce at Patchway, with assistance from Smiths Industries and Dowty. The DECS was fitted to a GR. Mk3 (XV277) and successively improved systems and development engines were flown in the aircraft between 11 March 1982 and 1987. Software was refined and fine-tuned to solve the problem of slow throttle response, and the engine was able to reliably provide 100% thrust on take-off (on earlier Pegasus engines there was tendency for thrust to stagnate at 92%). An important by-product of the DECS was that it allowed engines to be changed without requiring full-power-run-ups, making engine changes in field easier to accomplish. A development Mk 105 Pegasus 11-21 with DECS was ready in time to be installed in the first development Harrier GR. Mk5, ZD318, which first flew on 23 April 1985.
The need to provide a “deck alert” capability made McDonnell Douglas determined to improve VTO and hover performance; the company designed a new retractable air dam which helped trap a cushion of air between the gun pods or newly designed ventral strakes. They were closely based on new Lift Improvement Devices (LIDs) designed by Hawker Siddeley (like the big flaps) but not adopted by the British company during the period in which increased thrust seemed to offer the best way forward. The LIDs trapped a cushion of air below the fuselage, and helped prevent the re-ingestion of recirculated air form the nozzles, adding equivalent of 1200lb (5.34kN) of extra lift.
Naval Air Systems Command demanded a “full-scale” wind tunnel model of the new AV-8B wing, and a simple boilerplate replica of the new wing, intakes and flaps (together with an instrumented Pegasus 3) were fitted to the grounded second AV-8A (158385) for tests in NASA’s vast 80 x 40-ft (24.4 x 12.2-m) wing tunnel at the Ames Research Center. These tests were successful , and flight-worthy examples of the new wing were fitted to two more AV-8As (158394 and 158395) which became the YAV-8B prototypes. The first made its maiden flight on 9 November 1978, and the second followed on 19 February 1979. The second aircraft was subsequently lost on 15 November, when the pilot ejected following a flame-out. As well as the new wing, the two YAV-8Bs were fitted with the new YF-402-RR-404 engine that featured distinctive extended zero-scarf forward nozzles, which were more fully enclosed and which prevented the jet efflux from “splaying outwards”.
The YAV-8B proved to be much “draggier” than the original AV-8A, even after modifications to the wing root fairing, intake cowl, and inboard underwing pylons. This made aircraft significantly slower, although it did have much better payload/range characteristics. The USMC could finally look forward to a Harrier which could fly more than a “20-minute sortie”. Brief consideration was given to retrofitting new wing to existing AV-8As, but this option was soon rejected, since it gave an unacceptable increase in tail plane loads. The new LIDs were incorporated in 47 AV-8As, which underwent a SLEP to become AV-8Cs.
The enhanced performance of the YAV-8B was sufficient to prompt the US DoD to fund a Full Scale Development batch of four Harrier IIs in FY79.
AV-8B Harrier II
Spoiler
First of the next generation - The Day Attack variant
A flight of five AV-8B Day Attack Harrier (Day Attack Harrier aircraft lacked FLIR of later Night Attack Harrier variant) aircraft of VMA-513 in formation
McDonnell test pilot Charlie Plummer took the first FSD AV-8B on its initial hover check on 5 November 1981, by which time the British had signed up to buy the aircraft so they all had British-built rear fuselages. These aircraft also introduced MDD’s entirely new nose and revised, extended center fuselage. The new forward fuselage was of composite construction, and weighed 25% less than the equivalent section of the AV-8A. The pilot’s seat and cockpit floor were raised, giving more internal volume for systems and equipment, while a new rear-view canopy covered the raised cockpit, with a wrap-round windscreen in front. The rear fuselage was extended to compensate for extra weight forward, and the tail plane was redesigned, with an aluminum leading edge and a detachable trailing edge of honeycomb construction. From second FSD aircraft, all AV-8Bs were fitted with the smaller 70% version of the British-designed LERX, although, interestingly, the larger 100% LERX eventually was adopted on later aircraft. Four of the seven pylons were plumbed for the carriage of auxiliary fuel tanks.
When the USMC procured its first-generation Harriers it did so on the basis that the aircraft was an “off-the-shelf” item, and while some systems were replaced during service to optimize the aircraft for its USMC role, others had to be retained until the advent of a “clean piece of paper” in the shape of Harrier II. They included the aircraft’s INAS (The Marines preferring to use TACAN) the use of LOX (instead of an OBOGS) and the need for a laser designator. The USMC was particularly keen to replace the Harrier’s twin 30-mm cannon, since they were logistically difficult to support (using ammunition which was unique in the US forces) and were not adequately protected against electro-magnetic interference onboard the ship. For the AV-8B, McDonnell Douglas replaced the twin ADEN guns with a single GAU-12/A Equalizer 25mm Gatling gun. The gun was housed in the port cannon pod, with ammunition (300 rounds of link less Oerlikon KBA) layered in the starboard pod, and supplied to the gun across the “bridge” which doubled as a lift enhancer. The new gun enjoyed a very high rapid rate of fire, being driven by engine bleed air at up to 9,000 rpm and firing 3,600 rpm. The new gun was optimized for strafing ground targets.
Unlike the AV-8A and the AV-8C, the AV-8B featured almost from the start the Hughes AN/ASB-19(V)-2 Angle Rate Bombing System, proven in the A-4M Skyhawk. It was optimized for dive attack profiles and was linked to the new AN/AYK-14 mission computer and the SU-128/A HUD. The first two FSD aircraft initially flew with “solid” noses and extended test instrumentation probes, but later aircraft had distinctive glass nose associated with ARBS. Inside the cockpit, the AV-8B was a very different aircraft to any of its predecessors. Whereas the original Harrier cockpit had been entirely analog (unkindly described by some as an ergonomic slum), the AV-8B used a cockpit based on that designed for the F/A-18 Hornet, which in the late 1980s was regarded as the benchmark modern fighter cockpit with its HOTAS controls and large MFDs.
The Harrier II was made easier to fly in an effort to reduce the high attrition rate. Advances in technology allowed the use of a sophisticated three-axis Sperry Stability Augmentation and Attitude System (SAAHS), linked to a Departure Resistant System (DRS), minimizing pilot workload in the hover and during the transition to and from the hover. The SAAHS even allowed hands-off vertical landings to be made, demonstrated by Bill Lowe in February 1983. A USMC report entitled “Frosty Nozzle” had addressed the EW and secure communications shortcomings of the original AV-8A, and as a result the AV-8C had incorporated a KY-28/TSEC secure voice radio, AN/ALE-39 dispensers, ALR-67 RWR, and provisions for the ALQ-126C DECM pod. These systems were used from the start by the AV-8B, which was also planned to use the troubled ASPJ jammer.
A pilot production batch of 12 F402-RR-404A-engined AV-8Bs was ordered in FY82, the first of which flew on August 1983, Like the four FSD aircraft, the pilot production AV-8Bs were originally delivered with a double row of suction relief doors on the intake lips, but they were deleted when the intake was refined to improve the airflow. Early aircraft were subsequently retrofitted with the new single row of intake doors. FY83 saw a limited production batch of 21 aircraft, towards a planned total of 328 aircraft, a number was soon reduced to 286, including the FSD aircraft and three aircraft transferred to Italy. The pilot production aircraft were fitted with F402-RR-404A engines, subsequent aircraft were (delivered from mid-1985) being powered by the F402-RR-406 (Pegasus 11-21). The F402-RR-406 cured early surge problems, and gave a longer life, with a hot-end inspection at 500 hours and a TBO of 1,000 hours. The engine had maximum lift rating of 22,800lb (101.40kN), though a combat rating gave a maximum rating of 24,500lb (108.96kN) in level flight. The new engine’s turbine section ran about 10°-20°F cooler, improving component life.
The Harrier II attained its Naval Preliminary Evaluation in June 1982, opening the way for an Initial Operational Test and Evaluation (IOT&E) by VX-5. The AV-8B began to enter service in December 1983, initially with VMAT-203, the Harrier training unit, which received the first of the pilot production batch on 12 January 1984. The first of eight front-line (“gun”) squadrons, VMA-331, was formally commissioned on 30 January 1985.
Striking in dead of the night - The Night Attack variant
AV-8B (NA) Harrier II of VMA-311 preparing to land aboard the USS Tarawa (LHA-1)
The retirement of the Marines’ last A-6Es in April 1993 left the Corps without a dedicated long-range all-weather heavy attack aircraft. The Corps, did, however, enjoy a considerably expanded medium-range night/all-weather capability with its squadrons of F/A-18Ds, and with its night-attack-capable Lot 12 F/A-18Cs. The enhanced capability of the Harrier II placed increased emphasis on longer range and night operations, in just the same way that the RAF found itself requiring greater night-attack capabilities in its Harriers, and at much the same time. McDonnell Douglas was awarded a $2.1 million design definition contract for a night-attack Harrier in late 1985. This aircraft was originally known as the AV-8D, although it subsequently became the Night Attack AV-8B. A trial at NWC, China Lake, flew a podded GEC Marconi FLIR on a TA-7C, with the pilots wearing Cats Eyes NVGs. It was decided that the proposed Night Attack AV-8B should be similarly equipped.
In 1989, GEC Sensors received an initial £10 million contract for FLIRs for the new Harrier variant. MDD designed a neat installation for it above the nose, allowing the ARBS to be retained. The Hughes AN/ASB-19(V) ARBS is a daylight-only device, and is therefore redundant during night operations. The new US night-attack aircraft had a new expanded field of view HUD (20° azimuth by 16°, from 14° azimuth) to allow 1:1 correlation of the FLIR picture (20° azimuth by 13°) overlaid on the HUD. The aircraft also featured a new multi-purpose color display , and a CRT-based digital map display, which retrieved data from an optical compact disc in the Hamilton Standard AN/ASQ-194 data storage set. The pilot was provided with GEC Cats Eyes Generation III NVGs (with a field of view of 40° in azimuth by 30°) giving better peripheral vision, outside the 22° cone covered by the FLIR. The Cats Eyes NVGs featured prisms below the image intensifiers. No provision is made for NVG disconnect on USMC AV-8Bs, so use during take-off and landing is prohibited.
The Night Attack Harrier also took advantage of a new engine, the Pegasus 11-61, known in the US as the F402-RR-408. This engine was developed directly from Britain’s XG-15 engine technology demonstration program, which had been jointly founded by the British MoD and Rolls-Royce on a 70:30 basis. The new engine had improved fan aerodynamics, and single crystal turbine blades, among a host of improvements and modifications. The hot end inspection cycle was doubled to 1,000 hours, and lifecycle cost was asserted to have been reduced by 40%. Engine thrust was dramatically improved, with Rolls-Royce claiming a short lift wet rating of 23,800lb (105.85kN), and McDonnell Douglas claiming 24,500lb (108.96kN). The USMC rating was 23,400lb (104.07kN). Despite British origins, the 11-61 was not adopted for retrofit on RAF Harriers, though its testbed was a black painted GR. Mk5, ZD402.
Very significantly, the AV-8B(NA) was fitted with four extra Tracor AN/ALE39 chaff/flare dispensers above the rear fuselage, giving the aircraft a total of 180 flares or chaff cartridges, compared to 60 on standard, baseline AV-8B. The 87th single-seat AV-8B was built as the first AV-8B(NA) prototype, flying on 26 June 1987 and beginning a three-month evaluation at China Lake. The first production AV-8B(NA) was the 167th single-seater, the second FY89 aircraft. From then until the introduction of the Harrier II Plus, all single-seaters built were AV-8B(NA)s. VMA-214 was the first squadron to receive the Night Attack Harrier from September 1989, and all four Yuma-based units were re-equipped by September 1992. Only two units had started to transition to the variant by the time Gulf War broke out, and, with only about 15 delivered, it was not worth sending them to the theatre of operations.
AV-8B+ Harrier II
Spoiler
Long range missile slinging Harrier - AV-8B+ Harrier II
AV-8B Plus preparing to take off from USS Peleliu at night
The Harrier force was unlucky not to be able to field the more advanced AV-8B Harrier II Plus in the war, since the radar-equipped Harrier might have proved more versatile and might have silenced some of the critics, although all USMC fast jets in Desert Storm were used almost exclusively in the air-to-ground role, principally by day. Quite apart from its enhanced air-to-air potential, the Harrier II Plus was described by McDonnell Douglas as having a 74% improvement in day attack capability and a 31% improvement by night. One of the radar’s stated purposes was to feed slant range information to AN/ASB-19(V)2/3 ARBS, which was retained, although its nose-mounted TV tracked was obviously supplanted by the radar antenna and the radar. The radar could also be used for terrain-mapping, target location, acquisition and identification and terrain avoidance.
Design of a radar-equipped Harrier began in 1988, after a joint announcement from BAe and McDonnell Douglas in June 1987 that they intended to develop a radar-equipped variant, initially as a private venture. The US Marine Corps became increasingly interested in the new Harrier derivative, as did Spain and Italy, leading to the September 1990 signature of a tripartite Memorandum of Understanding between the four nations to develop a new variant. Alenia and CASA each gained 15% shares in the program. It was announced at that stage that the aircraft would use a Hughes AN/APG-65 pulse-Doppler radar, almost identical to the radar used by the F/A-18 Hornet, albeit with a smaller (24 x 28-in/60 x 71-cm) scanner to fit the Harrier’s smaller nose contours and 34-in (86-cm) diameter radome. The software was also modified, and a new circuit card was provided for the target data processor. Some black boxes were redistributed within the fuselage, but the installation was as much like that in the Hornet as was possible. The radar could provide range and bearing information for anti-ship missiles like Harpoon or Sea Eagle. The radar had a range of air-to-ground modes for ranging, moving target indication, mapping and navigation, and nine air-to-air modes. In essence, McDonnell Douglas hoped to transform the AV-8B into a STOVL clone of the Night Attack F/A-18C - an understandable desire when two of the initial three customers were already Hornet operators, and since the primary operator, the USMC, was increasingly relying on the Hornet. Anything which brought increased commonality between Harrier and Hornet was useful.
Had this not been a major consideration, it might have made more sense to adopt the GEC-Marconi Blue Vixen radar as used by the British Sea Harrier FA.2, a radar already being considered as an APG-65 replacement in some proposed F/A-18 upgrades. Blue Vixen was already integrated with AMRAAM in the Sea Harrier, with test firings beginning in March 1993. Addition of the new APG-65 radar added a 1,000lb (454kg) weight penalty, but this was relatively insignificant since all Harrier II Pluses were powered by the more powerful 23,800lb (105.85kN) F402-RR-408 (Pegasus 11-61) engine. Other changes to the II Plus included adoption of the RAF-type wing, with a 100% LERX and, most significantly, four pylons per side, including the dedicated AAM pylons on the undercarriage outriggers. The combination of uprated engine and LERX, in particular, improved performance by a significant margin. Inside the cockpit, the new variant has an additional MFD to allow the display of radar data.
The Harrier II Plus was based on the Night Attack AV-8B, and retained full night-attack capability and standard night-attack equipment, although the aircraft had a redesigned over-nose FLIR fairing (of more angular and more constant cross-section) which was reportedly more aerodynamically efficient and easier to manufacture. Like the Night Attack aircraft, the II Pluses had the 100% LERX, with twin Goodyear AN/ALE-39 chaff/flare dispensers on each side on upper rear fuselage and with a lengthened ram air intake at the base of the of the tail fin. The aircraft also had a new over-wing UHF antenna, which also served as the antenna for the AN/APX-100 IFF set. The second FSD AV-8B served as the aerodynamic prototype for the Harrier II Plus, and carried inert AIM-120 AMRAAMs. The aircraft was also intended from the start to operate with a BVR anti-ship missile - AGM-84 Harpoon being the obvious choice.
MDD modified the 205th single-seater (164129) to serve as the FSD Harrier II Plus after receiving a $20 million contract from Naval Air Systems Command. The aircraft first flew on 22 September 1992, a month ahead of schedule, in the hands of McDonnell Douglas test pilot Jackie Jackson. The aircraft was delivered to the NAWC-AD for testing, before transfer to the NAWC-Weapons Division at China Lake. It was joined by the first production Harrier II Plus from 23 April 1992. The second went to VX-5 for OT&E and the third to VMA-542 after briefly undergoing carrier suitability trials.
Sources:
Spoiler
- Harrier in action - Squadron/Signal Publications - Don Linn
- Harrier - The V/STOL Warrior - Osprey Military Aircraft - John Dibbs and Tony Holmes
- World Air Power Journal - Volume 32 - Aerospace Publishing Ltd
Thank you for reading!