The Gloster Javelin
The Gloster Javelin was the first British night / all-weather fighter designed specifically for the purpose. Although the development of the aircraft proved convoluted and it was not built in large numbers, it provided useful service for the British Royal Air Force (RAF) for over a decade. This document provides a history and description of the Javelin.
Gloster Javilin Origins
In early 1947, the British Air Ministry released two requests for proposals to the country's aviation industry. The first request was designated F.43/46 and specified a day interceptor, while the second request was designated F.44/46 and specified a night fighter.
The Gloster company submitted designs in response to both requests, with the day interceptor design given the company designation of "P.234" and the night fighter design given the designation of "P.228". The two designs could not have been more different: the P.234 day interceptor was a radical design by the standards of the time, a delta-winged fighter with a vee tail, while the P.228 night fighter was essentially an evolved derivative of Gloster's classic Meteor day fighter.
Other manufacturers submitted proposals. There followed a confusing shuffling of specifications and design submissions, the final result being that in early 1948, the Air Ministry ordered the construction:
- Three prototypes for a day-fighter requirement of the single-engine, single-seat Hawker P.1067 design, which would become the Hawker Hunter.
- Three prototypes for a night-fighter requirement of the twin-engine, two seat, radar-equipped de Havilland DH.110.
- Three prototypes for a night-fighter requirement of the twin-engine, two seat, radar-equipped Gloster "GA.5", which was an evolved version of the Gloster delta design concepts, fitted with a tee tail instead of the original vee tail. In reality, five GA.5 prototypes would ultimately be built.
The Gloster Javilin ProtoypesInitial flight of the first GA.5 prototype, WD804, was on 26 November 1951 with Gloster chief test pilot Squadron Leader W.A. "Bill" Waterton at the controls. The prototype was unarmed and otherwise not fitted with combat kit. It tended to buffet and flutter badly at high speeds, with the final result that it shook off both elevators on 29 June 1952. Waterton managed to get it back down on the ground without injury to himself, though the aircraft was totalled.
The second prototype, WD808, made its initial flight on 20 August 1952, but it spent most of the rest of the year on the ground while Gloster engineers worked on the buffet and flutter problems. It returned to the air in early 1953, but was unfortunately lost in a stall on 11 June 1953, killing the pilot, Peter Lawrence. The third prototype, WT827, performed its first flight on 7 March 1953; it was the first prototype to feature armament and radar. The fourth prototype, WT827, took to the air on 14 January 1954, to be soon passed on to the government Aircraft & Armament Experimental Establishment (A&AEE) at Boscombe Down for trials. The fifth and final prototype, WT836, performed its first flight on 20 July 1954.
Although the trials demonstrated a number of handling problems that were proving difficult to work out, a production order for the GA.5 had been placed in 1952, with the type to be formally designated "Javelin Fighter All Weather Mark 1 (FAW.1)". Initial flight of the Javelin FAW.1 was on 22 July 1954, with test pilot "Dicky" Martin at the controls. While many of the FAW.1s were used for test and trials, they were delivered in enough numbers to build up two RAF squadrons in West Germany in early 1956. There were still enough difficulties with the type to force the RAF to specify an unusual level of limits on the maneuvers that could be performed with it. 40 FAW.1s were built in all.
Gloster Javilin FAW.1
The Javelin FAW.1 provides a good baseline for description of the Javelin family. The FAW.1 was a very hefty-looking aircraft, built mostly of aircraft aluminum alloys with some steel fittings, with a broad fuselage, broad and thick delta wings, and a high tee tail with a swept tailfin and a triangular tailplane.
The wing featured hydraulically actuated flaps and ailerons. There were slotted spoiler-type airbrakes on the top and bottom of each wing; the flap was actually fitted forward of the airbrake under each wing. Although early prototypes had a "straight" sweep with a sweep at 25% chord of 39.5 degrees, a "kinked" wing -- retaining the original sweep on the inner portion of the wing but lowering the sweep to 33.8 degrees outboard, resulting in wider wingtips -- was introduced in development, improving stall characteristics. The tailfin featured 47.6 degrees sweep at 25% chord, while the tailplane sweep was 42.8 degrees at 25% chord. The rudder was hydraulically actuated as were the elevators, with the entire tailplane able to adjust incidence under electrical power, apparently for takeoffs and landings.
The aircraft was fitted with hydraulically-actuated tricycle landing gear, with all gear assemblies featuring single wheels. The nose gear retracted backwards while the main gear pivoted from the wings in toward the fuselage. The FAW.1 featured five fuel tanks in each wing, plus two fuel tanks in the forward fuselage, for a total of twelve internal tanks in all. US Air Force pilots who had flown Javelin prototypes during development had been critical of the type's endurance, and so dual flush-mounted belly tanks with a capacity of 1,137 liters (300 US gallons) each were developed. These tanks were known as "bosom tanks" or "Sabrinas", the last being a nickname commonly applied to brassiere-like fixtures on British aircraft of that era, in reverence of a busty pinup girl who nobody seems able to remember now.
The pilot and radar operator were accommodated in a tandem-seat, air conditioned cockpit under an all-round vision canopy that slid back to open. It was actually a four-piece canopy, with the rear segment sliding back over the fuselage to allow the radar operator in the back seat to get in and out, and the second segment sliding back from the windscreen segment over a short fixed third segment to allow the pilot in the front seat to get in and out. Early prototypes featured a different canopy scheme, with a solid metal rear cover featuring twin small portholes on each side, on the basis that the back-seater would be able to see his radarscope better; radar operators replied that they would prefer to see where they were going . Both aircrew sat on Martin-Baker ejection seats.
The aircraft was powered by twin non-afterburning Armstrong-Siddeley Sapphire Mark 6 (Sa.6) turbojet engines with 36.9 kN (3,765 kgp / 8,000 lbf) thrust each. Original design concepts had envisioned Rolls-Royce Avon engines instead, but they proved not powerful enough. The round inlets of the engines were spaced far apart, but the engines were fitted at an angle and the exhausts were set next to each other in the rear to reduce thrust asymmetry if an engine failed. There was a little pointed "pen-nib" fairing between the upper exhausts; early production did not feature this fairing, which was introduced to reduce buffeting. The engines used pyrotechnic starters -- essentially what looked like a giant shotgun shell was inserted and ignited to produce gas that turned over an engine, resulting in a cloud of black smoke at startup. The pyrotechnic starters had an unfortunate tendency to cause engine fires every rare now and then.
The FAW.1 was fitted with Airborne Intercept Mark 17 (AI.17) radar and four 30 millimeter Aden revolver cannon, with two mounted in each wing. Early prototypes had a rounded nose radome, but this configuration was too subject to erosion and was quickly replaced by a pointed radome. Initial concepts had envisioned armament of two 30 mm Aden cannon and two 11.4 centimeter (4.5 inch) recoilless guns, but though the RAF was very enthusiastic for a time for this big recoilless gun, probably fortunately it was a passing fancy, with attention moving on to guided air-to-air missiles (AAMs). It was assumed from the outset that the Javelin would eventually have AAM armament, but aircraft development outpaced missile development and the FAW.1 relied on the four cannon for armament.
The standard color scheme for the Javelin through its operational life was a disruptive pattern of dark sea green and dark sea gray on top and medium sea gray underneath. Some photos show Javelins with a similar color scheme except for brown substituted for the dark sea green, but this may just have been a quirk of image color. Of course, trials Javelins were sometimes painted in gaudy high-visibility schemes.
Gloster Javilin FAW.2 through FAW.9
The next production version of the Javelin was the "Javelin FAW.2", which was fitted with American Westinghouse AN/APQ-43 radar, know as AI.22 in British service. The AN/APQ-43 was supplied to the UK under the Mutual Defense Assistance Program (MDAP). The FAW.2 featured a larger nose radome, which could be pulled out and hinged to the side to give access to the radar for service; the FAW.1's radome, in contrast, had to be unbolted and removed. The FAW.2 was otherwise hard to tell from the FAW.1. Some sources claim that the Sabrina tanks were introduced on the FAW.2 and not used on the FAW.1, but this is hard to confirm.
In practice, although the AI.17 had suffered from teething problems, after some time in service it proved reliable enough, and though the AN/APQ-43 was a more sophisticated radar set on paper, it actually didn't prove to be much of an advance. Initial flight of the first FAW.2 was on 22 October 1955, and 30 FAW.2s were built.
The "Javelin Trainer Mark 3 (T.3)" was a dual-control trainer variant, with an elevated rear seat to give the flight instructor a better view and an extended three-piece canopy. It was 1.12 meters (3 feet 8 inches) longer than the fighter variants, giving it a total length of 18.4 meters (60 feet 5 inches). Radar was deleted but the cannon were retained; the longer fuselage helped maintain the center of gravity after removal of the radar, and also permitted fit of two more fuselage tanks, for a total of 14.
The Javelin T.3 also featured an "all moving" tailplane, discussed below. The initial flight of the first T.3 was on 6 January 1958 -- in terms of mark numbers, the T.3 appeared out of sequence, with higher fighter marks being introduced before it. 22 T.3s were built.
The "Javelin FAW.4" was an attempt to improve the aerodynamic characteristics of the Javelin. The main change was fit of the "all moving" tailplane mentioned above, in which the entire tailplane was shifted hydraulically to provide elevator action. The tailplane actually retained elevators, but they were only used for trim. Other features included sets of "vortex generators" -- little fins applied in rows to the wings -- that set up air vortices over the wings to prevent "dead air" at low speeds, plus a stall alarm system; one of the problems with the Javelin was not only that it tended to go into dangerous stalls, it did so with little or no warning.
The improvements helped matters, but official limits on what maneuvers could be performed were still imposed on the FAW.4. The FAW.4 used the original AI.17 radar. The initial flight of the FAW.4 was on 19 September 1955, with a total of 50 FAW.4s built in all, production being split between Gloster and Armstrong-Whitworth.
The "Javelin FAW.5" was an FAW.4 with a new wing that incorporated flexible fuel tanks in the outer wings to counter complaints about the Javelin's poor endurance. Some sources describe the FAW.5 as an FAW.1 with the new wing, implying that it did not incorporate the aerodynamic improvements of the FAW.4, but pictures show the wing to be fitted with the rows of vortex generators and presumably the FAW.5 also had the all-moving tailplane. Initial flight of the FAW.5 was on 26 July 1956, with 64 built, again with production split between Gloster and Armstrong-Whitworth.
The "Javelin FAW.6" was exactly the same as the FAW.5 but used the AN/APG-43 (AI.22) radar. Initial flight was on 15 January 1957 and 33 were built, all by Gloster.
All these marks featured the Sapphire Sa.6 engine, in the form of the Sapphire 102 or similarly-rated Sapphire 103. The next Javelin, the "FAW.7", was fitted with uprated Sapphire Mark 7 (Sa.7) / Sapphire 203 engines with 48.9 kN (5,000 kgp / 11,000 lbf) thrust each. It also featured an extended rear fuselage to reduce drag, with the pen-nib fairing deleted; a yaw stabilization system linked to the rudder; and, significantly, new armament of four de Havilland Firestreak (originally Blue Jay) heat-seeking AAMs, carried on four underwing pylons. The missile fit was very clean aerodynamically and did little to impede performance.
The FAW.5 and FAW.6 had actually been designed to carry the Firestreak, but missile development was delayed, and in fact early FAW.7 production was delivered without AAM capability, to be retrofitted later. Four drop tanks with a capacity of 455 liters (120 US gallons) each could also be carried on the pylons for ferry flights. AI.17 radar was retained as was Aden cannon armament, though in many cases two of the four cannon were deleted in the field. Initial flight of the FAW.7 was on 9 November 1956, though it took a year more to get the variant into service. 142 were built, with the production split between Gloster and Armstrong-Whitworth.
The last new-production variant of the Javelin was the "Javelin FAW.8", with Sapphire Mark 7R (Sa.7R) / Sapphire 204 engines, which were Sa.7s modified with a limited afterburning capability, providing the same level of dry thrust as the Sa.7 but 59.6 kN (6,075 kgp / 13,390 lbf) afterburning thrust each. The new engines also featured an isopropyl nitrate starter system that was supposed to be more convenient than the cartridge starter system, but it didn't turn out to be that big an improvement. Development of turbine auxiliary power units for later generations of aircraft would prove to be the real solution.
The afterburner could only be engaged at high altitude; due to the limited throughput of the fuel pump system, if reheat were engaged at low altitudes, it would actually cause a loss in thrust. Unlike earlier marks, the FAW.8 featured distinctive variable nozzles that extended from the rear fuselage. The FAW.8 featured the revised tail and Firestreak capability of the FAW.7 but used the AN/APG-43 (AI.22) radar. It also featured some aerodynamic enhancements, including drooped leading edges on the outer wing panels, an aileron pitch stabilization system, and an autostabilization system for the rudder. First flight of the FAW.8 was on 9 May 1958, with 47 built, all by Gloster. The last performed its initial flight on 8 August 1960. It was not only the last of 433 Javelins built, including the five prototypes, it was also the last Gloster aircraft built.
This wasn't quite the end of the story, since Gloster rebuilt 116 FAW.7s to "Javelin FAW.9" standard by fitting Sapphire Sa.7R afterburning engines as well as the drooped wing outer leading edge. The conversions followed production of the FAW.8 and were completed in December 1961. Apparently a good number of FAW.7s never flew in their original configuration, being stockpiled and then updated to FAW.9 spec before introduction to service.
|GLOSTER JAVELIN FAW.9|
|Wingspan||15.85 meters||52 feet|
|Wing area||86 sq meters||926 sq feet|
|Length||17.30 meters||56.75 feet|
|Height||4.88 meters||16 feet|
|Empty weight||10,900 kilograms||24,000 pounds|
|MTO weight||14,300 kilograms||31,600 pounds|
|Max speed||1,140 kph||710 mph|
|Service ceiling||16,100 meters||52,800 feet|
|Range||1,540 kilometers||954 miles|
|Crew||Two, pilot and radar operator|
|Engine type||Armstrong Siddeley Sapphire 7 turbojet|
|No. of Engines||2|
At least 40 FAW.9s were further updated with a long (6 meter / 20 foot) bolt-on refueling probe on the right side of the nose, to be designated "FAW.9(F/R)". The nose refueling probe configuration had been selected after earlier, unsuccessful trials of wing refueling probes. Top speed was restricted with the probe fitted. These machines were later further improved to "FAW.9R" standard by being qualified to carry four 1,046 liter (275 US gallon) external tanks.
Gloster Javilin in service
A total of 19 RAF squadrons flew the Javelin at one time or another, with the type operating from the UK, West Germany, Cyprus, and Singapore. Javelins operating from Cyprus often operated in very tense circumstances, intercepting Turkish aircraft penetrating Cyprus airspace. Egyptian aircraft performed similar probes once or twice, and Javelins also occasionally intercepted and escorted Soviet bombers and patrol aircraft flying through the eastern Mediterranean.
From 1963, there were border tensions between Malaya and Indonesia, with Singapore-based Javelins deployed to Malaya to perform border patrols. Ten Cyprus-based Javelin FAW.9Rs were deployed to Zambia in late 1965 after Rhodesia declared independence from Britain. They flew south with a full load of six external tanks, raising a protest from the Egyptian government when they simply overflew Egyptian airspace to get there. The deployment lasted well into 1966. Conditions were primitive, with one Javelin losing a Firestreak when a nest of termites crawled up the landing gear and ate the solid propellant out of the missile.
No Javelin ever fired a shot in anger. By the early 1960s, British home defence units were converting to the English Electric Lightning , with the last Javelin in front-line service in Britain phased out in 1964. Javelins continued to serve in Germany until 1966, in Cyprus to 1967, and Singapore until 1968. No Javelins ever flew in foreign service.
Pilots were generally fond of the Javelin, since it was sturdy and reliable, with a roomy cockpit, good field of view for the aircrew, and generally pleasant handling. Engine-out handing was regarded as very good, and it was one of the first RAF aircraft that could break Mach 1 (if only in a dive). Even in maturity, however, with the all-moving tailplane, control-surface stabilization systems, and stall-warning system, it couldn't be thrown around in any serious fashion, though pilots never seemed to express much concern about that issue, seeing it as a matter of simple pilot training and competence. Nicknames that have been recorded include "Flying Triangle", "Flying Flat Iron", "Ace Of Spades" (for its profile as seen from below), "Harmonious Drag Master" (for its distinct sound), and "Grovelin" (for reasons unknown, but it sounds unflattering).
In exercises, the Javelin proved an effective interceptor against contemporary combat aircraft. At altitude, it was more than a match for a Hunter, with the Javelin's big wings giving much more lift and its highly effective airbrakes quickly allowing a Javelin pilot to turn the tables on a tail pursuer. Some believed that the Javelin could have been retained in service longer had it been fitted with updated radar and missiles, using it as a "missile truck" to perform air patrols. However, aircraft development was moving rapidly in the 1950s, leaving the Javelin well behind the learning curve, and there was no interest in even evaluating the Javelin with the improved Red Top derivative of the Fireflash.
A goodly number of Javelins, in many cases FAW.1s, were used as test and trials platforms. One evaluated the Napier Gyron Junior turbojet, while another flight-tested the Rolls-Royce Avon RA.24R afterburning Avon. A few Javelins remained in service with the A&AEE well into the 1970s, sometimes being painted in eye-catching red-white patterns or bright orange overall. While no Javelins remain airworthy, about ten survive as ground displays.
There were a range of Javelin concepts that were not built. A strike aircraft based on the standard Javelin was considered, but given a thumb's down. In 1953, Gloster began design work on a "thin wing" Javelin, starting out as a standard Javelin with a new highly swept, thin chord wing for both interceptor and strike applications, gradually evolving to the more heavily redesigned Gloster "P.376" interceptor, with a thin steeply-swept wing, a stretched fuselage fitted with twin afterburning Rolls-Royce Olympus turbojets and featuring area ruling, and armament of cannon, two Blue Jay / Firestreak AAMs, and two Vickers Red Dean AAMs -- the Red Dean being an oversized AAM with an active radar seeker that never got beyond flight tests.