Hawker Siddeley Harrier

The Hawker Siddeley Harrier and its British Aerospace successors served the Royal Air Force from 1969 until 2010. Across two substantially different generations, the aircraft combined a jet’s speed and weapons capacity with the ability to take off from short strips and land vertically. The familiar name concealed an extraordinary sequence of engineering changes: the original GR.1 and GR.3 were comparatively compact Cold War strike aircraft, while the later GR.5, GR.7 and GR.9 belonged to the extensively redesigned Harrier II family. Their shared defining feature was the Rolls-Royce Pegasus engine, which directed thrust through four rotating nozzles.

Harrier history is therefore more than the story of an unusual flying machine. It is the history of the RAF’s attempt to preserve tactical air power when airfields might be destroyed, its adaptation of land-based jets for the Falklands campaign, its shift to precision attack, and its integration with Royal Navy carrier aviation. The aircraft’s limitations were as consequential as its strengths. Vertical take-off severely restricted useful payload and fuel, demanding carefully planned short take-offs, tanker support, maintenance and forward logistics. The Harrier’s achievement lay in making that demanding system work in operational service.

Origins: P.1127 and the Kestrel

British work on a practical vectored-thrust aircraft developed during the 1950s through collaboration between Hawker designers and engine specialists at Bristol Siddeley. Ralph Hooper played a central role in Hawker’s P.1127 design, while the engine programme drew on the work of Stanley Hooker and his colleagues. Sydney Camm’s wider Hawker organisation supported the project. The decisive arrangement used a single engine with two forward cold-air nozzles and two rear hot-exhaust nozzles, all capable of turning to redirect thrust. Small reaction-control outlets helped the pilot control attitude when airflow over the conventional surfaces was insufficient.

The P.1127 first flew in October 1960, initially undertaking tethered and vertical trials before the programme demonstrated transitions between hovering and wing-borne flight. This was not a straightforward extension of ordinary jet flying. In the hover, conventional aerodynamic control surfaces had little effect, while the aircraft’s attitude, height and engine power were closely coupled. The pilot had to learn to manage nozzle angle and reaction controls as a distinct flying regime.

The Kestrel, which first flew on 7 March 1964, developed the concept into an evaluation aircraft. The Tripartite Evaluation Squadron brought together British, American and West German pilots to investigate its practical military value in 1964–65. The trials demonstrated possibilities for dispersed basing and tactical flying, while exposing the training, maintenance and handling demands of V/STOL operations. The production Harrier followed this experimental work. Its own first flight was on 28 December 1967. Those three first-flight milestones belong to different aircraft and should not be conflated.

How vectored thrust worked

The Pegasus was a turbofan with four swivelling nozzles linked so that the pilot could direct thrust downward, rearward or to intermediate angles. Pointing the nozzles down produced lift; rotating them rearwards allowed the aircraft to accelerate conventionally. During the transition, both the engine and wings contributed to lift. Reaction-control jets at the nose, tail and wingtips gave authority in the hover. These controls required specialist training and created handling characteristics unlike those of an ordinary fast jet.

A vertical take-off required engine thrust to support the aircraft’s full weight. That made it particularly restrictive when carrying substantial fuel or weapons, especially in hot weather. A short rolling take-off allowed the wings to generate lift and made better use of the engine’s available thrust. The aircraft’s operational value was therefore usually realised through short take-off and vertical landing, rather than routine heavily laden vertical departures. A hover also consumed fuel quickly, and the hot exhaust imposed demands on landing surfaces. Nozzle control could assist manoeuvring in forward flight, but spectacular air-show demonstrations should not be mistaken for standard combat tactics.

The Harrier could dispense with a long runway, but it could not dispense with fuel, ammunition, spare parts, trained engineers, secure communications or suitable operating surfaces. The RAF’s dispersed-airfield doctrine depended on an organised support system rather than the aircraft operating independently from any patch of ground.

GR.1 and the first operational squadrons

The GR.1 entered RAF service in 1969, with No. 1 Squadron at RAF Wittering becoming the first operational unit. The GR.1 entered RAF service on 1 April 1969; No. 1 Squadron flew Harriers in the London–New York air race in May. Its designation reflected the intended ground-attack and reconnaissance roles, not an air-superiority fighter mission. The original aircraft had no fighter-interception radar and relied on its pilot, weapons and tactical information to locate and attack targets. Its characteristic under-fuselage cannon pods housed 30 mm ADEN guns, while external stations could carry conventional strike stores.

Training was unusually demanding. Pilots needed competence in conventional jet flying, low-level navigation, weapons delivery, hovering, short take-offs and vertical recoveries. The Harrier Conversion Unit became No. 233 Operational Conversion Unit in October 1970, building a specialist training establishment at Wittering. Two-seat T.2 and later T.4 aircraft enabled instructors to teach the distinctive handling safely. Training and conversion units were essential to the operational force, but they should not be counted as additional frontline strike squadrons.

The GR.1A and subsequent GR.3 introduced improvements to power and equipment. The GR.3’s longer nose housed the Ferranti Laser Ranger and Marked Target Seeker, while improved navigation and defensive systems supported more demanding tactical operations. The Pegasus 103 was associated with the mature GR.3. The changes mattered because a dispersed strike aircraft still needed to find targets accurately and survive increasingly sophisticated defences.

RAF Germany and the dispersed strike concept

Harrier squadrons in RAF Germany were intended to operate in the demanding environment of a possible Warsaw Pact offensive. Fixed airfields could be attacked by missiles, bombs or other weapons before aircraft could respond. Dispersal offered a way to complicate an opponent’s targeting problem. RAF planners examined roads, clearings and prepared short operating surfaces from which Harriers might launch and recover, supported by mobile engineering, fuel and armament teams.

Nos. 3, 4 and 20 Squadrons were among the units that operated the first-generation Harrier in RAF Germany. No. 20 Squadron’s original Harrier period ran from December 1970 to March 1977, after which its numberplate transferred to a Jaguar unit. That is distinct from No. 20 (Reserve) Squadron’s much later role as the Harrier conversion unit. Nos. 3 and 4 Squadrons continued the German Harrier commitment and subsequently transitioned to Harrier II equipment.

The aircraft’s tasks included close support, battlefield interdiction and attacks on enemy concentrations and communications. Flying from short sites near the anticipated battlefield could shorten response times, but also placed maintenance crews and aircraft within reach of enemy ground forces and artillery. Concealment, mobility and rapid turnaround were integral to the system. Exercises in Germany and northern Europe tested how far the concept could be sustained under difficult weather and logistical conditions. The Harrier was not a substitute for every conventional strike aircraft; it was a specialised response to a particular operational problem.

Norway, Belize and overseas readiness

Cold-weather deployments to Norway tested the Harrier force’s ability to operate with limited infrastructure in conditions very different from those of Central Europe. Snow, ice, darkness and severe temperatures complicated both aircraft handling and support. The deployments also reinforced NATO’s ability to move tactical air power to its northern flank.

In July 1977, six GR.3s of No. 1 Squadron deployed to Belize with Victor tanker support following a military mobilisation in neighbouring Guatemala. The detachment became No. 1417 Flight in March 1981 and remained part of the British garrison until its withdrawal in 1993. The aircraft’s ability to operate from relatively modest facilities was useful, although any sustained deployment still required extensive supporting personnel and supplies. Overseas detachments also gave aircrew experience of unfamiliar climates and long-distance deployment procedures.

After the Falklands War, the Harrier remained part of Britain’s South Atlantic air presence. No. 1435 Flight was re-formed in the Falklands with Harriers after the war and subsequently operated Phantoms. A separate No. 1453 Flight operated Harriers at Stanley from 1983 to 1985. The two flight numbers refer to different units and must not be confused. This post-war detachment must be distinguished from No. 1 Squadron’s combat deployment during the 1982 campaign.

The Falklands War: getting the GR.3 to sea

Argentina’s invasion of the Falkland Islands in April 1982 created an urgent requirement for combat aircraft thousands of miles from Britain. The Royal Navy’s Sea Harrier FRS.1 was central to fleet air defence, but the task force also needed additional aircraft for ground attack. RAF No. 1 Squadron supplied Harrier GR.3s. Although the GR.3 was designed primarily for land operations, its short take-off and vertical landing capability allowed it to be adapted for carrier use.

The deployment demanded nine-hour ferry flights and aerial refuelling to reach Ascension Island. Aircraft were then carried south aboard the merchant ship Atlantic Conveyor. They were protected against the marine environment before being transferred to the task force’s carriers. On 18 May the aircraft were redistributed, with the RAF GR.3s joining HMS Hermes. The squadron flew its first operational sortie on 20 May, after a brief period of work-up. The Royal Navy’s Sea Harriers had already been engaged in the air campaign.

These roles were complementary but distinct. Sea Harriers possessed radar and Sidewinder armament suited to fleet air defence; RAF GR.3s concentrated on offensive support, attacks on Argentine positions, armed reconnaissance and attacks on airfields. The two aircraft shared a basic vectored-thrust lineage, but they did not have identical equipment or missions. RAF pilots and maintainers had to master carrier procedures and operate under conditions for which their land-based aircraft had not originally been designed.

Falklands combat, losses and San Carlos

From HMS Hermes, RAF Harriers attacked airstrips, installations and ground positions across the islands. On 23 May Wing Commander Peter Squire led a four-aircraft strike against the airstrip at Dunnose Head, a mission described in the RAF Museum’s account of GR.3 XZ997. Operations demanded accurate navigation over open water, rapid attacks in poor weather and careful management of fuel for recovery aboard the carrier. The GR.3 carried conventional bombs, rockets and cluster weapons. Laser-guided bombs were employed very late in the campaign, with the RAF Museum recording four bombs dropped on the day before the ceasefire, two of which struck their pinpoint targets. These were a limited but historically important use of guided weapons, rather than the normal method of attack throughout the war.

Four RAF GR.3s were lost during the campaign. Harrier losses demonstrated the danger of low-level attack. Flight Lieutenant Bob Iveson survived the loss of his aircraft, evaded capture and was eventually recovered by British troops. Such incidents underline that a V/STOL aircraft was not immune to ground fire or the hazards of low-level combat. The limited number of available aircraft, carrier deck capacity and maintenance resources made every loss significant.

A temporary forward operating facility was constructed at San Carlos after British forces established a foothold. It provided an option for forward refuelling and recovery, although the carriers remained central to sustained operations. The improvised strip illustrated the Harrier’s flexibility, but also the engineering effort needed to make it usable. Following the Argentine surrender on 14 June, a fuller facility was established at Port Stanley. Following the ceasefire, a detachment moved ashore to Port Stanley on 4 July 1982, armed with Sidewinders for air-defence duties. The RAF maintained a Harrier presence at Stanley until 1985, when the new airfield at Mount Pleasant became available. The Falklands experience validated the aircraft’s expeditionary usefulness while also exposing the importance of naval integration, tankers, shipping and ground support.

The Harrier II: a major redesign

By the 1980s the original Harrier’s payload, range and avionics limited its usefulness against modern defences. The Harrier II was a substantial redesign developed through Anglo-American cooperation, not simply a GR.3 with a new engine. It incorporated a larger composite wing, revised structure and modernised systems, offering greater fuel capacity and weapons flexibility. British Harrier II aircraft followed the American AV-8B development line but received equipment and modifications to meet RAF requirements.

The GR.5 was the first British second-generation production version. Conversion work at No. 233 Operational Conversion Unit was underway in 1988; its first in-service GR.5 flight from Wittering took place on 30 March that year. No. 1 Squadron became an early frontline recipient. Because two-seat Harrier II trainers were not immediately available, conversion initially used first-generation trainers alongside the new single-seat aircraft. The transition required revised engineering procedures and flying techniques as well as different weapons and mission systems.

Later versions developed this new airframe rather than returning to the original GR.1 structure. For a combined RAF Chronicle history, the GR.5, GR.7 and GR.9 deserve their own account: they represented the later half of the RAF Harrier’s service and much of its post-Cold War combat career.

GR.7, night attack and precision weapons

The GR.7 brought improvements in avionics and night-attack capability, including equipment for navigation and targeting in demanding conditions. As the RAF moved away from the expectation of a single large armoured battle in Central Europe, Harrier units increasingly prepared for expeditionary deployments and multinational air campaigns. A useful strike aircraft now needed to operate with other NATO forces, identify targets accurately and limit unintended damage.

Harrier II aircraft served during operations associated with Iraq and the Balkans. The Harrier II subsequently took part in British operations connected with Iraq, Bosnia and Kosovo. The aircraft’s contribution to the 1991 Gulf War should not be conflated with later operations against Iraq. In Afghanistan, GR.7 aircraft deployed in September 2004, followed by GR.9 aircraft later in the campaign. These campaigns should not be reduced to a claim that the Harrier performed an identical role in every conflict. Operational conditions, basing arrangements, available weapons and coalition tasking changed from one theatre to another. In the Balkans, aircraft faced the demands of coordinated air operations and the need to distinguish military targets in complex terrain. During the Iraq campaign of 2003, Harriers supported the wider coalition air effort.

Precision strike capability developed through targeting equipment, navigation improvements and compatible guided weapons. The GR.7 was a significant step beyond the original GR.3’s simpler sensors, but modern targeting also demanded detailed intelligence, communications and strict procedures. Harriers were part of a larger air system rather than independent weapons platforms.

Joint Force Harrier and the Royal Navy

The RAF’s Harrier II force became increasingly integrated with Royal Navy carrier aviation. Joint Force Harrier was established in 2000, bringing RAF and naval squadrons into a shared organisation. This followed the Royal Navy’s earlier use of the Sea Harrier, a separate aircraft developed from the first-generation family. The distinction matters: the Sea Harrier was optimised for fleet air defence, whereas the RAF Harrier II and the later naval-operated GR.7 and GR.9 were principally strike aircraft.

Joint operations allowed aircrew, engineers and aircraft to support land and maritime missions through a common force. RAF Cottesmore became a principal base, while HMS Invincible and HMS Ark Royal provided carrier operating experience. The naval component eventually included 800 Naval Air Squadron flying the GR.9. Carrier operations still required specialist deck procedures, aircraft preparation, weather assessment and coordination with the ship’s flying-control organisation.

Joint Force Harrier was not simply an administrative arrangement. It represented a change in how Britain organised its remaining fixed-wing carrier strike capability and shared expertise between the two services. The Harrier’s original dispersed-basing concept had developed into a system that could operate from land bases and aircraft carriers, although the aircraft remained constrained by fuel, weapons load and the need for robust logistical support.

Afghanistan and the final GR.9

In September 2004, six GR.7s of No. 3 Squadron deployed to Kandahar after a British government decision to provide coalition close air support. Afghanistan became one of the final major theatres for the British Harrier force. RAF and Royal Navy personnel operated Harrier II aircraft in support of coalition land operations, often with the challenge of identifying fleeting targets near friendly troops or civilians. Close air support depended on communications with forward air controllers, accurate situational awareness and carefully controlled weapons employment. The aircraft’s ability to carry precision weapons and operate in demanding conditions was important, but sorties also relied on tankers, intelligence and airfield support.

The GR.9 and GR.9A represented the final British development standard, with improved mission systems and integration of additional weapons. The GR.9A designation distinguished aircraft fitted with a more powerful Pegasus engine configuration. The changes extended the Harrier II’s usefulness in contemporary operations, but they could not remove all of the aircraft’s inherent limitations. Hot-and-high conditions affected performance, while increasing demands for sensors and weapons placed pressure on available payload.

British Harrier squadrons returned from their sustained Afghanistan commitment in 2009, after five years of operations. The type’s later service therefore combined its original advantage of flexible basing with the sophisticated mission planning and precision-strike procedures of modern coalition warfare. By this stage the Harrier was far removed from the relatively simple GR.1 that had entered RAF service four decades earlier.

Squadrons, conversion and evaluation

No. 1 Squadron was the first RAF Harrier operator in 1969 and continued through the transition from GR.1 and GR.3 to Harrier II variants. Nos. 3 and 4 Squadrons operated the type in RAF Germany and subsequently flew Harrier II aircraft. No. 20 Squadron’s first Harrier service, from December 1970 to March 1977, must be distinguished from No. 20 (Reserve) Squadron’s training role beginning in September 1992. That reserve squadron succeeded No. 233 Operational Conversion Unit and continued until March 2010, when the conversion role passed to No. 4 (Reserve) Squadron.

No. 233 OCU had been central to training since 1970 and was responsible for introducing pilots to V/STOL operations and later the Harrier II. Specialist units and flights also formed part of the story: No. 1417 Flight in Belize, Nos. 1435 and 1453 Flights in the Falklands, and test-and-evaluation organisations including No. 41 (Reserve) Squadron. These should not all be presented as equivalent frontline squadrons. Royal Navy units, including 800 Naval Air Squadron, joined the later joint force and are best identified separately from RAF formations.

No. 1435 Flight was re-formed after the Falklands conflict, while No. 1453 Flight separately operated Harriers at Stanley in 1983–85 and No. 1417 Flight was associated with Belize. The Harrier’s squadron history thus spans changing numberplates, locations and roles. A simple count of five squadrons is misleading without defining whether it means frontline RAF units, conversion units, specialist flights or naval squadrons. The aircraft’s service history is more accurately conveyed by identifying each unit and its role.

Withdrawal and final flights in 2010

The Strategic Defence and Security Review of October 2010 led to the decision to retire the British Harrier force. The withdrawal was earlier than many in the services had expected and ended the United Kingdom’s operational Harrier capability. On 24 November 2010, four Harrier GR.9 aircraft made their final launches from HMS Ark Royal, about 40 nautical miles off Newcastle. The Ministry of Defence recorded the aircraft departing the carrier off northeast England, bringing an important chapter of British carrier flying to a close.

On 15 December 2010, sixteen Harriers flew a final formation from RAF Cottesmore. The participating aircraft represented No. 1 Squadron, No. 4 (Reserve) Squadron and 800 Naval Air Squadron. The event marked forty-one years of RAF Harrier service and the end of the combined RAF and Royal Navy force. The retirement date for the entire British Harrier family is therefore December 2010, not 1990, which refers to the disappearance of the first-generation RAF aircraft from frontline service.

The decision had consequences for carrier aviation and for the experience accumulated by pilots, engineers and support personnel. It also demonstrated that even a successful and distinctive aircraft could be withdrawn for wider defence-policy reasons. Preserved examples now document the contrast between the early GR.1, the Falklands GR.3 and the much larger Harrier II.

Variants, performance and production

The principal RAF single-seat versions were the GR.1 and GR.1A, the improved GR.3, the redesigned GR.5, the night-attack-capable GR.7 and GR.7A, and the final GR.9 and GR.9A. Two-seat trainers included the first-generation T.2 and T.4 and the later Harrier II T.10 and T.12. Naval Sea Harrier FRS.1 and FA.2 aircraft belonged to a related but distinct Royal Navy development line and are included here for context rather than confused with RAF ground-attack marks.

Technical data must be attributed to a specific version. The GR.3 used a Pegasus 103, conventionally quoted at approximately 21,500 lbf thrust, while later Harrier II aircraft used different Pegasus standards. The original GR.3’s wingspan, weight and weapons arrangements cannot stand in for those of the larger GR.9. Likewise, a quoted range may mean ferry range with external fuel rather than combat radius with weapons. The Harrier’s most important performance characteristic was not its top speed but the relationship between thrust, fuel, weapons, temperature and available take-off distance.

Production figures need equal care. Totals for first-generation Harriers, Sea Harriers, American AV-8 aircraft and British Harrier II production describe overlapping but different populations. The previous unqualified total of 278 should not be treated as the number of aircraft in the whole family. For this combined RAF history, an unqualified single production figure would obscure the distinction between generations and naval derivatives.

Historical significance

The Harrier was one of the most original aircraft to enter RAF service after the Second World War. It proved that a jet strike aircraft could operate without a conventional long runway, provided the aircraft was supported by the right training, engineering and logistics. In RAF Germany, that meant dispersal and survivability; in the Falklands, it meant putting land-based strike aircraft aboard a carrier at short notice; in later conflicts, it meant integrating a versatile strike platform into multinational operations.

The Harrier’s forty-one-year RAF career also reveals how much an aircraft family can change while retaining a common name. The GR.9 was not merely a polished GR.1. Its airframe, avionics, weapons and operational context were markedly different. Yet the fundamental problem remained the same: how to bring effective jet air power to places where conventional basing was difficult or vulnerable. The answer was never effortless vertical flight. It was a demanding combination of aircraft design, skilled crews and carefully organised support. That is the Harrier’s enduring place in RAF history.