Glasic International Aircraft Goshawk

GIA Goshawk
Early artist's impression of the Goshawk

The Glasic International Aerospace Goshawk is a fourth generation combat and third-generation Advanced STOVL aircraft. Designed as a replacement for the Harrier the Goshawk was, unlike the relatively niche-marketed Harrier aimed at a much broader range of missions and customers. The type's main employment is that of a strike fighter in the air interdiction and close air support roles; the Goshawk is however also used for the counter-air and reconnaissance roles in support of other types..

Under the Joint Force Goshawk (Comhfhórsa Spioróg mhór) initiative, both the ARTG and CRG operate the Goshawk as part of the ARTG's Ordú Ionsaí (Assault Command), including deployments on board the navy's two ski-ramp equipped aircraft carriers. The Goshawk has made significant contributions in such the ongoing conflicts in Tír Tairngire and Artanor as well as continuing to be forward based elsewhere in Vinya. In Tír Tairngire and Tír an Crainn the type's main function has been as a deep and close air support platform; until 2013 they also served alongside Harrier IIs

Design and development

Origins

In late 1978 Michael Murphy the Technical Director at Glasic International Aircraft (as it then was) tasked the future requirements office finding new ways to overcome the problems encountered with the earlier P.1205 project, mooted to replace the Harrier. This included the detrimental effects of using a PCB-equipped engine on an aircraft such as the Harrier or 1205. It appeared that the only approach to solve these problems was through innovation in the airframe's layout. Additionally, it had been proposed to power the P.1205 with a developed Pegasus engine but Murphy was aware that the Pegasus had limited growth potential, so sought proposals for all-new engines from Morris-Foley and Hennessy Aerojet. These would not only feature PCB but the core would also run much hotter than the Pegasus, while not requiring the water-injection system of the latter to achieve maximum thrust. In late 1978 Morris-Foley provided GIA with details of its Advanced Vectored Augmented Turbofan (AVAT) engine. Murphy's view was that this engine would have suitable growth potential over the Pegasus to as be a suitable powerplant to base any future designs around. Hennessy Aerojet proposed an engine derived from that developed for the P.1154 but this being seen as old technology only managed to survive the initial design process as a fail-safe in case of the AVAT’s failure.

In order to explore possible airframe options nine different configurations were developed. By November 1978 these included versions with and without canards, those with proving problematic with regard to the transitional period between the hover and forward flight. Of the nine variants proposed it was that which split replacing it with a pair of booms mounted under a notched-delta wing, this meant there was no structure at all aft of the engine nozzle which in turn immediately removed the problems of rear-fuselage vibration and exhaust damage while allowing the engine nozzle to be moved to the aircraft's centreline reducing pitch-up problems during transition. As an aside, aircraft survivability was enhanced thanks to the booms masking much of the exhaust plume as well allowing widely separated, duplicated aircraft systems reducing the likelihood of a single missile or shell hit knocking out such systems. The booms held the main undercarriage wheels as well as fuel and avionics. Each boom had a tail-fin at the rear with the forward sections being used for conformal weapons carriage, the booms would also allow a reduction in supersonic wave drag, a significant issue for previous supersonic design studies.

The first twin-boom aircraft was given the project number P.1212, the baseline aircraft being the notched delta previously selected. Power would be provided by an TF.422-48 (AVAT) or PCB Pegasus 11F-38, A number of brief studies were undertaken during 1979 looking at alternative wing plan-forms such as canards, tailplanes on the outboard positions of the booms and even 'reverse taper' with the booms at their tips. These were extensions of the nine original design studies previously drawn up, none showed any advantage, neither did the forward-sweep or additional single-fuselage studies, these two later becoming P.1214 and P.1213 respectively. Whilst none of these programs progressed beyond the paper study stage a low-speed wind-tunnel model of P.1212-2 was built and tested during 1980, demonstrating that the use of elevons for both pitch and roll control on the notched wing would be inadequate, thus the solution was the addition of tailplanes, identical in size and shape to the vertical tail surfaces, with this P.1216 became P.1216 in 1980

Due to a lack of interest from the government, work firstly proceeded on the development of a less ambitious program to upgrade the existing Harrier fleet with a larger wing amongst other improvements. Two prototypes were built from existing aircraft and flew in 1978, the same time that studies were going on behind closed doors at GIA. The government was content to continue down this path unless a major foreign buyer was found. By 1980 no such buyer had been found so the decision was taken to upgrade the legacy Harrier fleet Their opinion was that modifications would suffice in service until a suitable partner could be found, thus the enlarged wing design was preceded with but with the incorporation of leading-edge root extensions. By 1982 it was clear that although as a stopgap the upgraded Harrier fleet would suffice it would not be sustainable in the coming decades thus GIA was approached as the designers and manufacturers of the Harrier to investigate replacing the Harrier with a new type. By this time a full-scale mock-up of the P.1216 had been constructed at GIA which had been inspected by Queen Katherine I during her tour of GIA during the summer of that year.

Development of the P.1216 would continue at GIA until 1987 by which time second-generation Harriers had been ordered as yet another stop-gap measure. The design was frozen in early February of 1987 and the instruction to proceed was received by May. The first aircraft flew in 1993 with the type's first air-show appearance the following year. By 1997 production-standard aircraft were entering service.

Description and role

The basic layout of the Goshawk was dominated by the need to keep the fuselage structure and systems away from the highly-energetic efflux of the PCB-equipped engine. This resulted in a twin-boom aircraft with a central nacelle mounted underneath the wing. The aircraft was predominantly constructed of second generation carbon fibre composites with Super Plastically Formed / Diffusion-Bonded (SPF/DB) titanium used in high-heat, high stress areas. The Goshawk features a highly-swept wing with a 55° leading-edge sweep angle of low-aspect ratio and modest (6-5%) thickness/chord ratio. The wing design originated as a way to minimise exposure to PCB efflux from the side nozzles but also serves to reduce supersonic wave drag and allowed for high angle-of-attack flight as well as lowering gust-response in low-level flight. A degree of static pitch instability, enabled by the triplex-FBW system improved subsonic lift and reduced trim drag in supersonic flight. Low-speed manoeuvrability was further enhanced by large leading-edge-route-extensions which also improved turn rate as well as the automatic deployment and retraction of leading and trailing edge devices.

Further developments

Even before the Goshawk had entered service, it had become clear that alternations would be required for the aircraft to be more capable in the counter-air role thus the forward section of the aircraft was re-arranged around the highly capable Blue Vixen radar. Additional avionics incorporated during this re-design included a boom-mounted forward-looking infra-red (FLIR), night-vision capable cockpit and a more comprehensive electronic countermeasures suite.

Some Goshawks were fitted with up-rated Morris-Foley TF-422-60, these were correspondingly designated as GR.1As; these Goshawks possessed significantly improved take-off and landing characteristics, could carry greater payloads further and with the introduction of hydraulically actuated nozzles on all three of the engine's nozzles possessed substantially improved manoeuvrability. Eventually the majority of the fleet would receive the up-rated engine. From 2007 a limited number of LITENING targeting pods had been made available to the Goshawk fleet, initially flown on one of the boom stations they were eventually integrated onto the fuselage's unused FLIR station, eventually this went on to become a fleet-wide change, this also allowed the carriage of the RECCELITE reconnaissance pod on the same station due to the system sharing the same form-factor as the targeting pod. In response to difficulties communicating with allied air-forces during exercises abroad the Goshawk fleet were upgraded with a new communications suite identical to that being fitted to the Venom fighter-bomber then being introduced.

A further substantial upgrade commenced in 2012 with the Joint Update and Maintenance Programme (JUMP), completed in 2015 this significantly upgraded the Goshawk fleet's core avionics, communications systems and weapon-systems integration. The programme was carried out incrementally with increments for each of the three areas to be updated, firstly under Capability A the aircraft received a full re-wire and integration of a new mission computer, this necessitated the replacement of the MIL-STD-1533 bus with an IEEE 1394 one. MIL-STD-1760 was also brought to those stations not yet retrofitted with it allowing for smart-weapons carriage on all stations. Under capability B the aircraft received enhancements to their secure communications, ground proximity warning and navigation systems (TERPROM), integration of Mode 5 IFF as well as the replacement of the aircraft's Blue Vixen radar with a MOTS AESA and the integration of an infra-red search and track system mounted in the nose in space previously occupied by LRUs for Blue Vixen. Capability C, the final part of the programme consisted of the integration and flight trials of a number of weapon systems in use with other ARTG aircraft such as Brimstone and JDAM.

Capabilities D and E were implemented after the initial programme had been completed, Capability D included the integration of a Link 16 data-link, auxiliary civilian communications system and a Tactical Information Exchange Capability (TIEC) system allowing for information from elsewhere to be displayed on the aircraft's heads-down displays. Capability E is the most recent update to the aircraft and only applied to a few two-seater aircraft, it consisted of the integration of am emitter locator system in the wing and tail booms as well as coating the aircraft in a radar-absorbing and infra-red-reflective paint for the DEAD mission.

Variants

GIA designations

Goshawk A

Single-seat aircraft with radar nose

Goshawk B

Twin-seat aircraft with radar nose

Goshawk E

Single-seat aircraft with laser nose, ostensibly export-orientated

Goshawk ET

Twin-seat aircraft with laser nose, ostensibly export-orientated

Goshawk G

Designation for ARTG CA.2Es

Aerfhórsa Ríoga na Tír Glas (ARTG) designations

CA.1

The CA.1 was the ARTG's first variant of the type. The GR1 considerably differed from the prototypes of avionics, armament and countermeasures.

CA.1T

The CA.1T were the original two-seat combat-capable trainers.

CA.1A

The CA.1A were CA.1s fitted with the more powerful TF-422-60 engine, the -60 engine provided some 4,400lbs of dry thrust more than the TF-532-08 and 4,250lbs more in afterburner.

CA.2

The CA.2 is is a substantial upgrade of the CA.1, focussing on the Goshawk's avionics and weapons. All CA.1 and CA.1As were upgraded under the JUMP programme

CA.2E

The CA.2E is a modification of the CA.2T for the DEAD mission. 16 were converted from CA.1Ts

CA.2T

The CA.2T are those trainers upgraded under the JUMP programme, all 14 remaining CA.1Ts were converted to CA.2T standard.

Operators

Tír Glas

• Aerfhórsa Ríoga na Tír Glas (ARTG)
• Cabhlach Ríoga de Tír Glas (CRTG)

Tír Tairngire

• Aerfhórsa Ríoga de Tír Tairngire (ARTT)

Tír an crainn

• Aerfhórsa Ríoga de Tír an crainn (ARTC)

Themiclesia

• Themiclesian Navy

Hallia

• Hallian Navy

Akeniran

• Akenirani Navy

Specifications

General characteristics

• Crew: 1 or 2
• Length: 55.88 ft (17.03 m)
• Wingspan: 34 ft (10.36 m)
• Height: 12.4 ft (3.78m)
• Wing area: 421.19 ft² (39.13 m²)
• Empty weight: 24,714 lb (11,208 kg)
• Loaded weight: 36,510 lb (16,560 kg)
• Max. takeoff weight: 34,847 lb VTO, 46,550 lb STO (18,804 kg VTO, 21,115 kg STO)
• Internal fuel: 11,795 pounds (5,350 kg)
  Boom fuel: 6,150 pounds (2,790 kg)
• Powerplant: 1 × Morris Foley TF.422-60 PCB vectored-thrust turbofan
  • Dry thrust: 31,400 lb (139.67 kN)
  • Thrust with afterburner: 44,600 lb (198.39 kN)

Performance

• Maximum speed:
  
  • At sea level: Mach 1.2 (920 mph, 1,480 km/h)
  • At altitude: Mach 2.0 (1,534 mph; 2,470 km/h) 40,000ft, 60% fuel, four MRAAM, four SRAAM
• Combat radius: 630 nmi (1167 km) with 2,500kg war-load on a hi-lo profile
• Ferry range: 2,310 nmi (4,278km) with drop tanks
• Service ceiling: 51,200 ft (15,606 m)
• Rate of climb: 60,000 ft/min (304.8 m/s)
• Wing loading: 88 lb/ft² (429.75 kg/m²)
• Maximum g-load: +9/-3g, +8 with fuel booms

Armament

• Guns: 1× LEX-mounted 23mm rotary cannon with 475 rounds OR 2x boom-mounted 23mm revolver cannon with 150 rounds each.
• Hardpoints: 4× under-wing, 2x wingtip-rails 12× conformal-boom and 1× centreline with a capacity of up to 23,000 lb (10,000 kg) of stores
• Rockets:
  
  • CRV7 70 mm rockets
• Missiles:
  
  • Air-to-air missiles:
    • Skybolt MRAAM
    • Viper SRAAM
    • Black Spear BVRAAM
  • Air-to-surface missiles:
    • Sabre
    • Spear
    • Black Spear Anti-Radiation Missile
  • Anti-ship missiles:
    • Skua
• Bombs:
  
  • BCT-450 Submunition dispenser
  • BCT-415 Submunition dispenser
  • BT series general-purpose bombs
  • BT-121 Guided Bomb
  • BT-122 Guided Bomb
  • Sagaris and Improved Sagaris series of guided bombs
  • Kesja and Kesja-L series of guided bombs

• Others:
  • ECM pods
  • LITENINGs, and RECCELITE reconnaissance pods
  • Up to 6 × 270 gallon drop tanks for ferry flight/extended range/loitering time

Avionics

• Blue Vixen or Bruxa