Image too large - LY910 Shadowhawk
Specifications:
General characteristics:
• Crew: 1 (2 for –B )
• Length: 20.6m (20.9 for –B )
• Wingspan: 13.3m
• Height: 3.6 m
• Wing area: 102m2
• Empty weight: 16,970kg (17,270kg for –B )
• Loaded weight: 25,970 kg (26,270 for –B )
• Max takeoff weight: 31,000 kg
• Fuel weight: 7,500kg
• Powerplant: 2× Lughenti Aerodrome L-116 (160kN ea)
Performance
• Optimised Performance maximum speed: Mach 2.6+ (2,880 km/h) at altitude (RCS(F)0.0001~0.0002)
• Optimised RCS maximum: Mach 2.2+ (2,655 km/h) at altitude (RCS(F) of ~0.00008)
• Cruise speed: Mach 1.6 (1,706 km/h) at altitude
• Subsonic (long-range) speed: Mach 0.8 (980km/h) at altitude
• Combat radius: 1,680 km
• Ferry range: 5,660 km
• Service ceiling: 19,800 m
• Rate of climb: 190 m/s
• Wing loading: 254.6kg/m² (nominal)
• Thrust/weight: 1.28
Armament
• Bombs and missiles: 4,000 kg in internal bay (six points, each rated to 950kg), 4,000kg on 6 (optional) underwing (wet) pylons, inboard rated to 2000kg, middle rated to 1000kg, outboard rated to 500kg (not exceed 2000kg munitions per wing).
• LY108 ‘Gideonschild’ 25mm automatic cannon, starboard wing root
Avionics
AN/APG-94 ‘Huldra’ LPI Active Electronically Scanned Array
AN/ASQ-240 'Apsca' Advanced Polyspectral Combat Sensor Array
LWR
RWR
GPS/TFR/INS
Contrail sensor
Abstract
The LY910 Shadowhawk is a single-seat twin-engine fifth-generation air superiority fighter aircraft designed to utilise cutting-edge stealth technology and super-manoeuvrability. While designed primarily for the air superiority role, it has additional capabilities that include ground attack, electronic warfare, signals intelligence, reconnaissance and maritime patrol. Lyran Arms is the sole sales body, and Executive Command maintains oversight of the subsystems production and integration.
Background and Conceptualisation
In the early 1990s, the Lyran Protectorate began in-depth examinations of the likely requirements for achieving and maintaining air supremacy in a high-threat battlespace. Specific attention was given to the air-to-air role, and of the criteria for an aircraft to replace the LY907 ‘Goshawk’, of which the Protectorate had fielded nearly 25,000.
Dubbed the ‘Lyran Advanced Fighter’ (LAF) program, the research and development for the LAF became one of the most intensively scrutinised and manpower-intensive design efforts that the Lyran Protectorate has undertaken. With a variety of high-capability aircraft coming into service internationally, the edge that Lyras had enjoyed for so long was seen to be rapidly degrading.
Several different concepts were submitted by a multitude of design teams. Many concepts were common, partly through convergent evolution, and partly through specification demands. Common areas included signature reduction, short-field performance, agility, supercruise capabilities, and battlespace awareness. It was rapidly established that the final design would include many emergent technologies and leading-edge methodology. By 1994, requirements became more specific, with many of the common areas becoming written in as essential elements of the design.
The LY908 and LY909 programs, running parallel, made contributions to the emerging design, but also of great importance was the role of espionage. Simple bribery, in most cases, sufficed to provide details of a number of Lockheed Martin and Northrop design features submitted to the American Advanced Tactical Fighter program, along with lesser but still significant disclosures from Boeing, Pratt and Witney, General Dynamics and Sukhoi. Primary efforts of these espionage programs went into the respective contractors’ own submissions and research into 5th-gen fighter aircraft, but subsidiary systems and research platforms have also been targeted. The results of the extensive espionage program, while not complete, have provided the Protectorate with a great deal of resources for reverse engineering as well as accelerating theoretical knowledge. In conjunction with input from the Varessan Military Technology conglomerate, this has lead to advances in the LAF design progressing far faster than would be expected of a platform of its complexity.
By early 2005, the LY910 was taking shape, a shape that seemed remarkably like a modified YF-23. When pressed, Lyras has always insisted on the similarities being a remarkable example of convergent evolution. The evident success of Lyran Intelligence’s operations being evident has not detracted from the potency of the aircraft that has become the beneficiary of those efforts; the Shadowhawk is a unique and potent aircraft which, although displaying its influences, is quite different from other fifth generation aircraft. Counter-espionage attempts by several states, notably including Bigtopia, have thus far been foiled, and the exact thinking and methodology behind the Shadowhawk’s unusual design and extremely high performance have remained, for the most part, a speculative to the outside world.
Shadowhawk on the tarmac, Lughenti Aerodrome, 31 July 2010
Propulsion system
The LY910 is the first Lyran aircraft designed to supercruise, and it does so powered by a pair of Lughenti Aerodrome L-116 engines. Based heavily on the Pratt and Whitney F119-PW-100 that powers the F22, the L-116 is however not based on forty years of research, but is instead based upon 5 years of research, based in turn upon 2 years of well-executed espionage. Much of the L-116 is therefore very reminiscent of the F119, although, again, the Protectorate, when pressed, attributes this to convergent evolution. Similarity should not be mistaken for congruence, however, as the engines are very different, although to someone in the know examining an LY910, the ancestry of the L-116 would be quite clear.
The L-116 is a very high thrust-to-weight ratio engine, and implements a number of features to improve performance and ease maintenance loads. It includes 40% fewer parts than most 4th generation fighter engines, and each part is designed with efficiency and durability (not initial unit cost) as driving factors. Computational fluid dynamics have enabled the design of the engine’s turbomachinery being unusually efficient, granting the engine more thrust with fewer turbine stages. These factors, coupled with the Electronic Flight and Engine Control System (EFECS) pioneered on the LY909, has cut requirements for support equipment and maintenance labour by 50%, a feature which itself also saves precious logistics space during wartime. It is estimated that the L-116 will require 75% fewer maintenance facility visits than its immediate predecessors or dissimilar analogues. The EFECS feeds information on airflow and power generation not only to the pilot-accessible cockpit controls, but also to the BMS, if present, simplifying logistics by keeping higher command and maintenance units appraised of the engine’s performance and readiness, and enhancing reliability and maintainability by a commensurate level. The provision of dual-redundant engine controls (in the form of two control units per engine, and two full-capability computers per control unit) together ensure virtually unmatched reliability in engine control systems.
Additionally, the EFECS is designed to provide real time data to maintainers on the ground, allowing them to troubleshoot problems and prepare replacement parts before the aircraft returns to base. According the Pratt & Whitney in regards to the F119 engine, this data may help drastically reduce troubleshooting and replacement time, as much as 94% over legacy engines. Lyran estimates are more conservative, and expect an 80% time saving, doctrinally.
Aircraft with these systems fitted benefit from a considerably lower incidence of unscheduled engine removal than did their un-augmented counterparts, a factor which leads to considerable savings in maintenance, and considerably higher readiness, both of which are highly appealing in a platform designed to operate in a high-intensity environment against the most capable of adversaries.
Both engines are buried within the Shadowhawk’s wing to conceal the induction fans and minimize their exhaust signature. The twin intakes are serpentine, and mounted in a conventional manner, ventral to the wing and on either side of the blended fuselage. The inlet mouths are variable, enabling maximum manoeuvrability, but certain high-intake configurations (automatically controlled by the EFECS) can compromise the platform’s signature reduction measures. Because of this, the variable inlets are, by default, locked in position, but can be manually activated to optimise aircraft performance.
In the same vein, the Shadowhawk uses two-dimensional thrust-vectoring nozzles, which can be deflected up to 30 degrees in the vertical plane. By default, these nozzles are locked to ‘0’, and thrust vectoring must be manually engaged, as the angled nozzles compromise the RCS and IR reduction measures for which the beaver-tail design is optimised.
When engaged, the platform’s variable inlets and thrust vectoring are employed to maximise performance in all regards, making the Shadowhawk more manoeuvrable, at the expense of marginally increased detection footprint. Doctrinally, Lyran Shadowhawks leave the hyper-manoeuvrability disengaged, unless engaging hostile aircraft at close range or engaging in a high-speed sprint. At the conclusion of the close range engagement, the nozzles are returned to ‘0’, and vectored thrust disengaged again.
The L-116 implements integrally bladed rotors, with disks and blades fashioned from a single piece of high-durability metal, generating improved fan performance and appreciably less air leakage, while simultaneously decreasing the likelihood of catastrophic failure along connection points such as weld-seams.
Wider and stronger fan blades have eliminated the requirement for the inclusion of an engine shroud, which has also served to push engine efficiency up by improving air flow.
One of the more blatant results of Lyran espionage activity has been the direct implementation of Pratt & Whitney’s high-strength ‘Alloy C’ titanium alloy in a number of engine components, including compressor stators, augmentors and nozzles, allowing the engine to run hotter and faster, permitting improved thrust, greater durability and improving engine efficiency still more. Similarly, the combustion chamber features thermally-isolated panels of high cobalt, oxidation-resistant material, which provides a similar downward pressure on maintenance, and improves overall reliability.
Initial problems integrating the components from a dozen different heritages were overcome by continual flight-trials, modifications and upgrades throughout the design and development stages, with the aircraft’s intentionally modular nature and very deliberate and methodical examination making the process of adjusting the engines for testing and evaluation considerably easier than would be the case for comparable aircraft.
Easy-access panels allow maintenance to be carried out on most of the engine without requiring a ladder, another feature for which maintenance teams are grateful. Further to this, the L-116 engine features all flightline-replaceable units (FRUs) no more than one deep, meaning that no parts need be removed to access FRUs. Each of these can be removed by means of one of five tools, all of which are provided in a commonly available flightline tool set.
Conformal fuel tanks can be fitted above each wing’s shoulder, flush against the fuselage, providing an extra 2,100L of fuel for enhanced range or station-keeping capabilities. These are optimised for modularity and ease of maintenance, and are not conducive to maintaining a low RCS, and thus can be easily removed should the mission not require their inclusion, or should they be needed elsewhere.
LY910 features extremely long range for an aircraft of its size and role, in part due to the fuel storage provided by the very large wing. The principle can be illustrated (and to some extent quantified) by the relationship between the F-22 and the hypothesised FB-22. The larger wing of the FB-22 provides for up to 80% more fuel than carried by the F-22, with a commensurate increase in range. On the LY910, this adjustment in design from trapezoidal wing with horizontal tailplanes to single large trapezoidal wing has been responsible for a commensurate range increase figure, up 20% without increasing drag.
As is what one would expect, an aerial refuelling probe is fitted, just behind the rear of the canopy, which can extend the aircraft’s range, theoretically, as far as pilot endurance allows. Deployment of the refuelling probe will adversely affect the aircraft’s RCS, but the probe has been specifically designed to offer minimal radar returns. It is likely that the radar signature of a refuelling Shadowhawk would be lost within the larger radar return of the presumably non-stealthy refuelling tanker.
Fuselage and wing design
The design of the LY910’s fuselage and wing borrows considerably from that of the YF-23 and X-44, and is designed around a large trapezoidal ‘flying-wing’ planform, featuring relaxed static stability and fly-by-wire technology to maintain attitude, while also allowing for very high aerodynamic efficiency, with commensurate range and payload.
The composites are molded by means of a process called ‘Resin Transfer Molding’, which differs from conventional compression molding in that the mold can be made from composites for low production cycles or with aluminium or steel for larger production. The differences between the two types being that metal has better heat transfer, hence quicker cycle times; metal lasts longer and deforms less, but at a higher cost. The main problem with this production route is that air can be trapped in mold and hence a method must be incorporated for allowing this air to escape. A number of solutions to the problem exist including extending one level of reinforcement beyond the cavity (with a 25% resin loss), appropriate vents and creating a vacuum in the mold (which also improves quality). Larger structures, better properties (less movement of fibres), increased flexibility of design and lower cost are some of the advantage this process has over compression molding due mainly to the low pressure injection. Given the very high amount of composite material on the LY910, this is an appreciable cost saving, if nothing else. Other benefits include rapid manufacture, capital (rather than labour) intensive production, ability to vary reinforcements easily or include cores such as foam and produce low and high quality products. RTM is used to fabricate more than 350 distinctive elements of the LY910, in areas as diverse as the engine’s intake rims and the load-bearing spars under the skin of the wings. RTM has driven down the cost of wing spars alone by 20 percent, and has halved the requirements for reinforcement parts within those spars. RTM is utilised to manufacture BMI, epoxy and carbon- or aramid-fibre components.
The Shadowhawk makes extensive use of thermoset composites (25% by aircraft weight), a percentage eclipsed only by titanium (55%). Of those thermoset composites, there is a 25/25/50 split between carbon- and aramid-fibres, epoxy-resin components, and Polybenzothiazole, which is a high-temperature resin obtained by reacting mixed toluides, sulfur and 4-aminophthalimide. Glass reinforced PBT resin composites have withstood temperatures over 500 °C for short periods and 350 °C for longer times. PBT was chosen over the next alternate, high temperature bismaleimide (BMI) composite materials, due to PBT’s better thermal tolerances. These materials have directly resulted in the high weight/performance efficiency the LY910 demonstrates. The skin, in particular, is almost entirely PBT, covered only by the RCS-reducing fibrous matting.
Titanium offers higher temperature resistance, and is stronger and lighter weight than most conventional aviation materials, while generally also being more demanding to produce and machine. This is somewhat offset by the traditionally extensive Lyran use of titanium, including in aviation grade on the LY909 Sparrowhawk, of which nearly half a million have been produced as of 29 July 2010.
Lyran experience with relaxed static stability made it an obvious choice, and computational oversight was brought over bodily from the LY909, a measure which considerably eased developmental workload. The high wing area has also served to bring about very low wing loading, a factor which contributes to the LY910’s unusually good agility. The fuselage and wing are only nominally different, with the fuselage itself providing considerable lift, particularly at high speed. As such the very low wing loading of 254kg per metre is, in practice, actually lower.
Both wings have a dual-spar structure with integral fuel tanks. Given the large wing area, these wing tanks grant the Shadowhawk considerable range, range far higher than the vast majority of ASFs in service.
Thermoplastic composites account for a little over 1% of the aircraft’s empty weight, and are also highly durable materials but, unlike the thermoset composites, thermoplastics can be reheated and re-formed; a feature exceedingly useful for items such as landing gear and weapons bay doors, where high damage tolerance is required. Also featured within the landing gear is Aermet 310 steel for high-shock areas, without significant weight gains. In addition to being harder and stronger than the Aermet 100 used on the F-22, -310, the similar composition is able to also benefit from the measures used to reduce landing gear corrosion, while also maintaining ductility and toughness.
Avionics and control interfaces
The Shadowhawk is at the very leading edge of avionics design. A wide variety of the most capable avionics that the Lyran Protectorate can produce have been implemented in the Shadowhawk.
The centrepiece of the avionics suite on the Shadowhawk is the AN/APG-94 ‘Huldra’. Sharing many similarities with the AN/APG-77 of the F-22, as well as the AN/APG-92 ‘Heimdall’ of the LY908, the ‘Huldra’ radar of the Shadowhawk is the Shadowhawk’s primary anti-air sensor. A very long range, multi-function, rapid scan system, the ‘Huldra’ is an active-element electronically scanned array radar, integrated into the airframe both physically and electromagnetically. Designed with low probability of intercept (LPI) capability at the forefront of the design, ‘Huldra’ is intended to provide pilots, and the wider battlenet, with detailed information about extant threats without allowing hostile radar detection of the parent aircraft, or the ‘Huldra’ radar emissions.
Based in large part upon the Lyran experiences building the ‘Heimdall’, the ‘Huldra’ is however a more capable and advanced system, with far lower likelihood of successful detection by radar warning receivers or EW aircraft, higher resistance to jamming, greater frequency agility and smoother power-throughput. The radar has very few mechanical parts (which are common to most other radars), improving reliability considerably.
Like the ‘Heimdall’, ‘Huldra’ utilises a separate transmitter and receiver for each of the antenna's finger-sized radiating elements. 1900 individual transmit and receive modules, situated behind each element of the radar, constitute the array. Each module weighs 15g, and has a power output of over 4W. The base-plate is polyalphaolefin (PAO) liquid-cooled to dissipate the considerable generated heat.
The AESA nature of the radar is also integral to its Low Probability of Intercept (LPI) capability. ‘Huldra’ defeats most RWR/ESM systems by virtue of being able to carry out an active radar search on RWR/ESM equipped fighter aircraft without the target knowing it is being illuminated. Unlike conventional radars which emit high energy pulses in a narrow frequency band, LPI AESA systems like ‘Huldra’ emit low energy pulses over a wide (often punctuated or non-continuous) frequency band using a technique called spread-spectrum transmission. When multiple echoes are returned, the radar's signal processor combines the signals. The amount of energy reflected back to the target is about the same as conventional radar, but because each LPI pulse has considerably less amount of energy and may not fit normal modulation patterns, the target will have a difficult time detecting the Shadowhawk. Each individual LPI pulse is only marginally above background radiation levels, a factor which further forces down the likelihood of successful detection of the ‘Huldra’ system.
‘Borrowing’ from the APG-79, copies of which were obligingly provided by a pair of moderately well reimbursed Raytheon employees (who are currently living under false identities somewhere in the Varessan Commonwealth), ‘Huldra’ offers simultaneous air-to-air and air-to-ground modes. This is achieved using highly agile beam interleaving in near-real time, providing the pilot (and datalinks) an extremely high degree of situational awareness and tactical flexibility. The system operates (primarily) in the X-band, and uses reciprocating ferrous phase shifters to allow beam positioning in a time-frame measured in tens of nano-seconds.
By implementation of Cromwell-backed system resource management, ‘Huldra’ automatically schedules tasks to optimise radar functions and minimise pilot workload, and, for that matter, to minimise data overload. Therefore, the radar can continue scanning while communicating with other aircraft and capturing ground imagery, and can simultaneously guide multiple weapons to multiple targets widely spaced in azimuth, elevation and range.
Non-Cooperative Target Recognition is also one of the ‘Huldra’ capabilities. Traditionally problematic, the AN/APQ-94 accomplishes this by generating an array of fine radar beams and generating a high-resolution image of the target by utilising Inverse Synthetic Aperture Radar (ISAR) processing. The targets own relative rotation generates a 3D image (by virtue of the doppler shift) of the target, which is then cross-referenced with a radar-picture database. Should this be insufficient, the details are cross-checked via the Cromwell system, although the onboard bank of radar images is very comprehensive.
Other ‘Huldra’ capabilities include high resolution synthetic aperture radar mapping (working in conjunction with other integral and external assets, this provides extremely detailed information concerning topography and surface conditions), multiple ground moving target indication and track (GMTI/GMTT), combat IFF, electronic warfare resistance and integrated ECCM, automatic target prioritising and more. The radar is able to reliably detect, acquire and track a 3m2 RCS target at 400km, and a target with a RCS of 0.01m2 at 90km. UAVs, cruise missiles and fifth-generation aircraft are thus all on the list of likely candidates for successful engagement by Shadowhawks.
‘Huldra’ is able to track 64 aerial targets, and engage 12 of them, eight if fired missiles are semi-active radar homing, rather than active. Previously a rarity in Lyran aerial warfare, the very low probability of intercept of the ‘Huldra’ has brought SARH back onto the table of options, and targets have sometimes been downed by radar-guided missiles without ever having realised that they had been detected, let alone illuminated, tracked, allocated a target priority, and fired upon.
Antenna Diameter 1400 mm
-Azimuth Coverage: 120 °
-Elevation Coverage: 60 °,
-Detection Ranges:
3m2 RCS: 425km
0.01m2 RCS: 90km
Track: 64
Engage: 12 (8 SARH)
As with the Warhawk and Sparrowhawk, the Shadowhawk uses a digital 'fly-by-optics' control system, with artificial stability control. The aircraft's design-inherent tri-axial instability (a feature also known as ‘relaxed static stability’ – RSS) allows for extremely high agility, to the point where manual operation alone is unfeasible. This situation changes as speeds increase, as the aircraft’s centre of gravity shifts rearward. Net neutral static stability, on the Shadowhawk, is at about Mach 1.3. For safety purposes, the stability control interfaces (as in the F16, LY908, LY909, and many other aircraft) are quadruple redundant. If combat damage has rendered all of these control interfaces inoperable, there isn't a plane left to control in any case, and the pilot will likely have long since chosen to eject, or have been ejected.
Due to the continual adjustments to the aircraft’s trim brought about by relaxed static stability, the LY910, as with any other aircraft with this feature, is actually constantly on the brink of losing control. To address this tendency, the EFECS utilises a multi-channel fly-by-light flight control system. This system accepts flight-control inputs from the pilot, and feeds it into the EFECS, which then adjusts the aerodynamic control surfaces (and possibly the thrust vectoring settings) to produce the inputted course and attitude changes.
A BALCOTH-type data-interface, similar to the F-35’s helmet mounted display, provides the pilot with high proportions of essential information without forcing him to look within the cockpit.
Image too large – Rockwell-Collins’ HMD for the F-35
The helmet provides relevant flight information to the pilot, displayed on the helmet’s visor, rather than onto a fixed cockpit HUD. This allows for the use of extremely high off-boresight weapon cueing, and for more specialised use of the glass cockpit’s three full 8” x 20” Lyran InfoWar Colour Multi-function Head Down Displays (CMFHDDs) are used in far more specific roles than generally the norm. Although interchangeable, by default the left hand CMFHDD is the primary flight display (PFD), which shows radar and moving-map related information. The full tactical situation can be (and often is) displayed on this moving map, with the relevant information fed into it by the operating battlespace management system. The right hand CMFHDD is (again, by default) the aircraft systems display monitor, which presents information pertaining to flight systems, such as the engine, slat and flap settings, weapons status and fuel quantities, and any damage sustained. Separate inset diagrams provide at-a-glance details of similar information regarding wing mates’ aircraft.
All displays are compatible with the night-vision displayed by the helmet through the BALCOTH interface, with some early developmental mishaps pushing home this requirement.
The Shadowhawk utilises the ‘Laertes IV’ zero/zero ejection seat, built under license from Symmetriad Corporation of Vault 10, and this (and the pilot with it) is inclined at the slightly higher-than-usual angle of 22 degrees, selected to improve pilot tolerance to high-g manoeuvres, and particularly aimed at reducing the incidence of gravity-induced blackout. As with the Sparrowhawk, which featured the same ejection seat, at the same angle, this degree of inclination was determined to be necessary, and the provision of a high-quality g-resistant flight suit is also strongly encouraged for flight crew.
The canopy is jettisoned by two dual-redundant rocket motors. Due to the presence of the rocket motors, the seats themselves thus lack canopy breakers, a factor which provides that modicum of additional visibility, which adds to the visibility gained by the absence of a canopy arch.
Again sharing the Sparrowhawk’s interface, the Shadowhawk is flown by means of left-hand throttle and right-hand stick, a deviation from the standard left-and-centre layout of most aircraft that is brought about, again, from the high-g loading that the aircraft is designed to take. The stick has some play, although it is actually the pressure that transmits instructions to the fly-by-wire and fly-by-light systems, as fixed sticks generated a tendency to over-rotate.
Most of the important control elements for the aircraft have been moved to the throttle and control stick, providing a hands-on-throttle-and-stick (HOTAS) interface for enhanced pilot control during high-g operations, and for improved ergonomics.
The Shadowhawk’s extensive sensor capabilities are linked to the battlespace network, while also possessing substantial internal (multiple-redundant) computational facilities so as to handle required downloads from that network or its own aforementioned sensor systems. As is the case with most Lyran-built vehicles, the majority of gathered information is NOT displayed to the operators, being generally not worth their notice in a combat situation, but is nevertheless known to the battlespace system (and to the aircraft itself), which determines relevant information, and displays to the operator/s as appropriate, in order to mitigate data-overload.
Data-sharing is of particular import during close-in combat, where the body of the aircraft itself may obscure the pilot’s view. The BALCOTH-interface, coupled with data-input from friendly sources, can project the location of the target to the helmet’s display, even if the no direct line of sight can be drawn to the pilot’s eye. Note that this feature ensures the absence of the traditional 6 o'clock-low blindspot, as the operator/s are able to 'see' by means of the sensor suite, and thus take action accordingly, in a way that would be impossible for aircraft using more conventional electronics. As the operator turns their head, the view pans, and the image displayed can be either a direct projection of the ground, air and environs, as would be seen with the naked eye were the vehicle's hull not in the way, or various overlays, magnification and enhancements that can be applied or superimposed to highlight important elements (such as friendly ground forces – very important during a bombing run). This requires near-completely lag-free, high-luminance, high-contrast, low-fatigue and high-resolution picture with no viewing angle effect or parallax error. Further, the pilot helmet features ambient light sensors, with automatically compensating night vision systems (imaged without command input), mounted on the inside of the displays, providing high-clarity resolution in all conditions, and enabling unusually high levels of night-fighting capability.
‘Considerations’ granted to employees of a number of major aeronautical manufacturers are believed to have assisted in the implementation of this technology.
The Shadowhawk has the most robust communications suite of any Lyran-flown or -built fighter aircraft, to date. The Shadowhawk features a satellite communications capability that integrates beyond line of sight (BLOS) communications throughout the full spectrum of missions, both in its primary air-dominance role, and in its secondary profiles. The Shadowhawk’s provision for battlespace networks aims to accelerate the observe-orient-decide-act cycle, and in the process to increase operational tempo at all levels of the warfighting system, and as such contains the leading edge in tactical- and operational-level datalinks, which provides for the sharing of data among flight- and squadron-members as well as a wide variety of other platforms. The default system, Cromwell II, is designed for ultra-high speed networking, high integrity transmission, and permits transfer of a wide range of data formats, from a multitude of compatible sources.
Available battlespace networks can utilise the Shadowhawk’s own systems, and those of other friendly platforms to autonomously locate and track targets, comparing the data received against known friendly positions, to avoid blue-on-blue engagements, and maximise speed of deployment of weapons against hostile forces. As a consequence, awareness and engagement speeds of the Shadowhawk are extremely fast, and all the more so when the agility of the platform is factored into calculations.
Targeting and display speeds are such that they allow real-time orientation and lag-free look-shoot capability, particularly when combined with high off-boresight-capable munitions. A single aircraft, without non-organic Cromwell-sensory system support, can independently track up to sixty-four aerial targets, and fire upon as many as there are weapons to release. When data-links from friendlies are able to handle more of the detection and processing load, the number of targets able to be tracked rises exponentially (assuming that load is not running at capacity, of course).
The Shadowhawk’s electrics are hardened and quadruple-redundant, and designed for ‘smooth degradation’, thus a system failure will result in the platform becoming, triple-redundant, then double-, before losing redundancy capability altogether. In testing, very little degraded broader system functionality to the point of loss of control or use of major systems, short of that that also destroys the aircraft itself (ie, direct damage).
High-grade hardening of computer systems and electronics is a Lyran norm, and the Shadowhawk is no exception. The immense potential of this as a feature of military systems was demonstrated in spectacular fashion during the Stoklomolvi Civil War, when Lyran warships not only saved the lives of countless Stoklomolvi civilians by defending them from nuclear attack on two separate instances, but also then, in both cases, were able to exploit the massive EMP side-effect the LY4032 'Rampart' counter-ballistic missile generates in nuclear defence. The result was a carrier battle group destroyed, to no Lyran loss (save the missiles fired to sink them). While not a land-based example, the lesson has been learned, and hardened systems are set to stay as a standard feature of Lyran electrics for the some time to come.
Present on the platform are a host of more standard avionics, with which (at least in general terms) most people familiar with the aerospace industry should be comfortable.
The primary passive combat sensor suite is taken directly from the LY908’s repertoire, and is housed on the aircraft’s underside, between the two engines. The AN/ASQ-240 Advanced Polyspectral Combat Sensor Array (APSCSA – normally referred to as the 'Apsca') features a 360 degree (ventral) scanning arc with multi-sensor, electro-optical locator/targeting system, complete with IR, low-light digital CCD TV, laser range-finder/designator, and laser spot tracker. The pod itself is 190cm long, 45cm wide, 205kg, and ranges out to 52km. The systems themselves are housed within easy-access area of the aircraft, however the relevant emitters and receivers are not so constrained. Differing systems are arrayed throughout the airframe, often within internally turreted sensor mounts to provide relevant coverage during for air to ground or air to surface operations.
Full-duplex Cromwell-datalink allows information to be processed and disseminated to friendlies, while it is received by the platform. The package, as a whole, dramatically increases capabilities for target detection, acquisition, recognition and engagement, and permits reliable all-weather, day and night engagement of multiple targets by a single aircraft, in a single pass. Further, the design is modular for ease of maintenance and upgrade, especially in the Sparrowhawk’s easy-access dorsal spine, and comes complete with a fair-wear-and-tear warranty for fifteen years, and technical support on-call to assist in maintaining it.
The Shadowhawk employs side-scanning functionality within the LPI ‘Huldra’ system to achieve the Lyran-standard terrain following radar capability, with inertial navigation and battlespace-network-backed global positioning systems operating in parallel, in order to minimise the likelihood of navigational error.
The Shadowhawk also carries the world-benchmark AN/ALQ-281 ‘Tiamat’ EW system as integral. By default, ‘Tiamat’ emitters are set to ‘off’. Should the Shadowhawk’s RWR systems determine that it has, in actual fact, been detected, ‘Tiamat’ provides world-leading EW capability as an option to enhance aircraft survivability and defeat radar-lock. AN/ALQ-281 'Tiamat' (Babylonian mythology – 'Dragon of Chaos') is a Lyro-Varessan electronic warfare system. The 'Tiamat' recievers are located in several points within the leading and trailing edges of the wings, while the transmitters are housed in the wing shoulders, and at the point of the aircraft’s rearmost ‘beaver-tail’. The system, when engaged, is capable of intercepting, automatically processing and jamming received radio frequency signals. The LY910's electronic attack capabilities involve using radiated EM energy to degrade, neutralise or destroy hostile force- or force-support elements. 'Tiamat' is one of the first EW platforms to use high-end solid-state emitters, coupled with dramatically elevated potential power throughput, and dynamic and pattern-probability frequency agile (PPFA) barrage and spot jamming to render all but the most potent radars impotent. Further, if the seeking radar is calculated to be capable of burning through the jamming, precisely timed utilisation of Cromwell-backed broad-spectrum DRFM (Repeater) jamming is implemented.
This capability is second to none, and places ‘Tiamat’-equipped aircraft at the very top of known NS-combatants in the active electronic warfare role. The receivers can also be used to detect, identify and locate those signals, providing ELINT/SIGINT either automatically or manually. When emissions control (EMCON) is required (which is most of the time in the Shadowhawk) the 'Tiamat' transmitters can be turned off, which thus, as one would expect, cancels the EM broadcasting. Unlike the earlier AN/ALQ-99 series, the 'Tiamat' utilises power generated by the aircraft to function. Given the very high power output of the LY910's LY-116 engines (160kN each), this has not adversely affected performance in any appreciable manner.
Signature Reduction
The Shadowhawk is termed a ‘deep stealth’ design, with attempts to drive down the detection threshold of the aircraft being very central to the design and research carried out on the platform.
According to reports submitted in November 2005, the US Air Force states that the F-22 has the lowest RCS of any manned aircraft in the USAF inventory, with a frontal RCS of 0.0001~0.0002 m2, marble sized in frontal aspect, with the F-35 having an RCS of 0.0015m2, similar to the B-2, and half that of the F-117. The RCS of the MiG-29, an aircraft not designed for radar cross-section reduction, is about 5m2. However, the LY910 has been designed based upon Northrop’s YF-23, an aircraft that, during the American Advanced Tactical Fighter competition, had a lower RCS than its YF-22 competitor. It was from that starting point that the Shadowhawk’s signature reduction was implemented. Many of the features of the aircraft are thus very telling of the LY910’s role as an extreme-low-RCS ASF, with returns roughly equivalent to a 02-bore ball-bearing. The methods behind the generation of such performance is held very closely guarded by the Lyran Protectorate, and are multitudinous.
In the broadest sense, there are two primary approaches to the implementation of passive radar cross section reduction. They are;
1. Shaping, which adjusts shape to minimise the strength of returning radio waves to a detector, and
2. Coating, which aims to achieving absorption or cancellation of incoming, returning and outgoing emissions.
Both of these approaches have to be utilised coherently and in an integrated and whole-of-package fashion to achieve the greatest feasible low observable levels over the appropriate frequency ranges in the electromagnetic spectrum. The utmost care is exercised to ensure that there are no salient features to contribute to the platform’s detection. As in a blackout, the game can be given away by one chink of light. Fortunately, low observable technology has matured sufficiently that conventional or para-conventional aerodynamic configurations can be implemented incorporating low observability without considerably negative aerodynamic performance or increasing costs significantly in the production phase.
Intakes for the engine are submerged into the structure of the wing itself, dramatically lowering both thermal and radar cross section. The inlet paths are serpentine, by virtue of this, and conceal the engine and fan-face from radar, while simultaneously redirecting radar waves into the engine, rather than back to the receiver.
The LY910, as is visible at first glance, utilises a ‘flying wing’ design, which reduces the number of leading edges, which are generally one of the highest sources of reflected radar. Further to this, the trapezoidal wing design shows an axial symmetry which also furthers RCS reduction. The Shadowhawk also uses a completely frameless canopy, in order to reduce radar returns from the windshield arc, and is only the second aircraft in production, anywhere in the world, to do this, without negative effects on structural integrity.
In an effort to avoid radar-reflective materials being used on the crucial outer surfaces, the Shadowhawk has made a very extensive use of composites, with 30% of its weight, and nearly 80% of its outer surface being composed of such materials. Most of the structural composites are bismaleimide and composite epoxy material, both of which are also employed on the F-22.
Unlike the F-22 (and SR-71), however, the LY910 uses a far more durable, low-maintenance structural fiber mat, rather than the Raptor’s high-maintenance radar-absorbent metallic paint. The net effect is almost identical, but the fiber mat is far less maintenance intensive, and does not require such careful management to maintain its properties. Panel edges are serrated, in order to minimise returns from panel boundaries, a feature particularly visible on weapon bay doors and undercarriage.
In planform, the LY910 is an extremely unusual design. By implementation of a highly unconventional shape, the aircraft has a very high degree of tri-axial instability, but simultaneously maintains a high top speed. By using the same angle, (a design technique called planform alignment) on all flying surfaces (i.e. the nose, wing fronts, wing backs and engine exhausts), the low-observability factors are subsequently also increased.
Unlike the LY908 and LY909, the LY910 uses a ceramic-matrix RAM on the engine exhaust nozzles to reduce radar and IR signatures, and a very large amount of wide-band RAM is used structurally on the leading and trailing edges of the low-aspect ratio wing.
Contrail sensors are fitted to the rear of the aircraft, and advise the EFECS system of the likelihood of the aircraft generating a contrail, the formation of which can be catastrophic for attempts to reduce detection footprint. EFECS then makes small adjustments to engine output to reduce contrail likelihood. If contrailing becomes unavoidable, the pilot is notified by audio cue that he should change altitude. There is, after all, little point in investing tremendous resources in defeating a sophisticated radar network if atmospheric conditions make detection by Mk1 eyeball almost a certainty.
Armament
The LY910 is an air superiority fighter, and as such its armament is focused on this task. Munitions loadout can broadly be divided into internally carried stores, externally carried stores, and gun. Up to 8,000kg of missiles and bombs may be carried. Weapons carriage is as indicated below, with internal carriage bays being indicated in light blue, and locations for external hardpoints in red.
In its primary air-to-air role, the Shadowhawk would carry a solely internal payload, composed of two short-range AAMs, and eight AMRAAM-sized weapons or six AIM-220 ‘Velvet Glove’ missiles, for medium-to-long range and long-to-extreme range engagement, respectively.
The Shadowhawk has the capacity to mount six wet underwing pylons, with the inboard pylons rated to 2000kg, middle pylons to 1000kg and outboard to 500kg. Each wing, however, is only rated to 2000kg in total, so applying the maximum loading to both inboard and outboard pylons will exceed the aircraft’s design tolerances.
Although designed as an ASF, the LY910 is more than capable of carrying additional weapons, including PGMs, JDAMs, or BGM-109s (or analogs). Some of these weapons can be carried internally, although many will exceed the size specifications for the internal bays. An example of a weapon that doesn’t would be the AGM-88 HARM, which many LY910s have carried. Further, the chart above is in no way exhaustive. The LY910 is expected to be compatible with just about any weapon system, with minimum effort. In most instances, only minor software adjustments are required to mount and fire air-launched weapons.
Note, many weapon systems having divergent software requirements, and as such it may not be possible to mount certain combinations. This is a limitation of weapon systems, not of the platform itself.
External pylons (and/or their stores) can be jettisoned in flight, which will, of course, return the aircraft to its clean, ultra-low RCS configuration.
The Shadowhawk is also the second Lyran aircraft to be equipped with the LY108 ‘Gideonschild’ 25mm automatic revolver cannon. Named after the commander of Lyras’ Aerospace Forces, High Marshal Walter Gideonschild, the LY108 was developed by the Protectorate Research and Development Commission to meet the requirements of the LY909 program, and with an eye to export and implementation in future Lyran and Lyran-aligned aircraft. Gideonschild is a single-barrel, gas-operated, linkless-feed system, breech-cylinder system, based heavily upon Mauser’s BK-27 weapon. Like the BK-27, the LY108 is a selective fire weapon, which employs fire at 1000rpm, 1500rpm and 2000rpm settings.
The LY108 fires 25x150mm projectiles, with an average weight of 255grams, and can appear in many variants, including (but not limited to) armour-penetrating, HE-Frag, HE(I) and tracer. Standard loadout is 400 rounds of HE-Frag, with 1:5 HE(I).
Recoil springs and a floating buffer make for very limited felt-recoil stresses upon the airframe, which improves accuracy and flight performance, and lowers maintenance burdens.
Ammunition is mounted laterally, and positioned adjacent to the feed mechanism, generally on the right-hand side of the barrel. Spent cartridge cases are ejected rearwards, and held in a collection bay for removal upon reloading. The weapon is air cooled, and is assisted by automatic ram air which is forced into the weapon and collection bay during and immediately after firing. This process also serves to purge both of any uncombusted propellant residue which may contribute to fouling. This improves weapon reliability, and further serves to reduce maintenance footprint.
High accuracy was a very important priority for the weapon, and steps were taken right from the design outset to obtain this. Aiming is provided by both a radar sight and a helmet-mounted predictor. It is compact, simple and rugged in construction, features implemented for maximum reliability and operational lethality.
Undercarriage
The LY910's undercarriage is a fairly standard, although naval-grade ruggedised, retractable tricycle type, with two wheels on the nose, and two single-wheeled legs just rear of the trailing edge of the wing, mounted on the fuselage. All tires are 'run-flat' variants, enabling the aircraft to continue to roll, even if one or more tire were to burst, and saving damage to the undercarriage, although control will doubtless suffer. Shock absorbers are fitted, as is a considerable amount of suspension, enabling landing on short and rough or unprepared terrain, and to conduct naval operations from most aircraft carriers. An arrestor hook can be fitted between the rear undercarriage legs for this purpose, and a bay is provided so that the arrestor does not compromise RCS-reduction measures.
Amenities
The Shadowhawk’s pilot sits semi-reclined, which serves to minimise g-force effects in-flight, which can be quite severe, due to the aircraft’s exceptional agility and high acceleration. Water is available for consumption, in flight, and relief bags allow pilots to vent their bladders, if required, without risking any of the sensitive equipment in the cockpit. The various control interfaces allow access and adjustment without removing hands from the left-hand throttle or right-mounted control stick, and the provision of the data-linked Laertes IV automatic ejection seat allows pilots to focus completely on the mission, without having to worry about when to time their ejection.
Export
The Shadowhawk comes in two variants, the LY910A single seat aircraft, and the two-seater LY910B trainer variant. The –B variant is 30cm longer and 300kg heavier, but is otherwise identical. Both cockpit stations of the –B model are identical, and control functions are interchangeable. The –B variant, it must be stressed, is otherwise no different from the –A, and is fully combat capable.
LY910A NS$205m
LY910B NS$207m
DPRs to the two marks together are available at NS$2.05trillion, which is equivalent in price to 10,000 aircraft. If less are required, numerically, purchase of aircraft on a per-unit basis is suggested in most instances.
At present, the LY910 is considered the absolute leading edge of MT military technology, or, if not the edge itself, within a very short distance of it. As such, due to the possibility of compromise of high-value technology, the LY910 Shadowhawk is only available for purchase to states signatory to the Bredubar Covenant. Discussions pertaining to this can be entered into via telegram to Lyran Diplomatic Command.
All queries and purchases can be lodged through Lyran Arms.
