F/A-352B Longsword

F-352B Longsword-class Starfighter The F-352B Longsword-class Interceptor (designated GA-TL2 in UNSC Air Force service) was the UNSC's primary atmospheric and exo-atmospheric superiority starfighter during and after the Human-Covenant War. The successor to the earlier F-352A Longsword-class Interceptor, The F-352B made a number of major and dozens of minor advances over its predecessor, largely focusing on better adapting to combating the Covenant. A capable multi-role craft with both atmospheric and exo-atmospheric capability, the Longsword, like its predecessor, was able to maintain speed and agility, powerful armament and strong armour in almost perfect balance, making it one of the few UNSC machines able to go toe-to-toe with it's Covenant counterpart and defeat it in battle.

Developmental History
In 2546 a need to replace, or sufficiently modify the F-352A Longsword was identified, as a result of rapidly increasing maintenance and replacement costs. However, it was not deemed to be a pressing requirement, and it was sidelined in favour of resource-intensive programs more essential to the ongoing war effort. It was not until 2554 that the need was re-evaluated, resulting in the introduction of the F-352B Longsword in 2561. The F-352B was designed for use with its own shield generator, however project budgets prevented this being included in the final production model. The Longsword saw numerous upgrades throughout its service life; the most major on its performance being the addition of a shield generator in the class' 2566 upgrade (which also included updated electronics systems). In 2569 the entire class saw an upgrade to its inertial compensation technology, whose effect was essentially reducing the Longsword's weight by 7%. In 2578, the F-352B saw its 50mm cannons replaced with XM502 Railguns in a lethality upgrade program, and additionally an upgrade to the craft's engines. Designed to be extensively modular in addition to versatile, its modularity allowed extensive upgrading and updating to the same basic design for decades after the Longsword's introduction. This allowed for the use of various Covenant-derived technologies either that the craft was designed for but not with, or that weren't even available at the time of its design. The majority of the Longsword's design elements, including the armour plating, weaponry and even internal space were modular. This allowed for a single craft to fulfil vastly different roles (though not simultaneously) through changing of modular sections, while the craft itself filled many similar roles resulting from its inherent versatility. The F-352B, through both its versatility and consistent upgrades, was not retired from front line action until well into the 27th century.

Operational History
The F-352B, as a result of its widespread nature throughout UNSC forces, participated in virtually every battle after its introduction, generally performing well against Covenant forces even when outnumbered. Longswords in particular played a major part in rapidly securing air supremacy for UNSC forces invading Bellerophon, allowing orbital reinforcements to quickly seize the planet.

In late 2568 the Covenant began a renewed assault on UNSC worlds, hitting several colonies in conflicts including the Battle of Hyperion, Battle of Ariel, Invasion of Whitefall and the Battle of Highgate. All this placed strain on the taxed UNSC Navy, which struggled to meet the demands caused by dozens of simultaneous, protracted engagements. The F-352B played an important role in these battles, engaging invading Covenant forces in space and preventing the vast majority of hostile troops reaching the ground, in conjunction with other UNSC Navy, Marine and Air Force units. The Longsword's dual atmospheric/exo-atmospheric nature gave it a distinct advantage when facing Covenant forces, as it could effortlessly transition between raging spatial battles and vicious land-based ones.

In late 2569, when the Covenant reached its peak of aggression against humanity, the UNSC executed Operation: CIRCUMVENT, which had been in planning stages for the previous nine months. The F-352B was critical in the operation's success, escorting several SPARTAN-III fireteams to the target, a Covenant resupply post, designated Sterling-5. The two Longsword squadrons then proceeded to draw most Covenant spatial forces away from the SPARTANs, who were forced to operate in vulnerable exoatmospheric conditions. The eight Longswords also managed to neutralise a significant portion of the Covenant's deployed single ships, destroying 27 Seraphs while receiving no losses in return. The Longswords then proceeded to successfully tie up Covenant reinforcements until the arrival of several UNSC Navy Battlegroups, following which they participated in the rest of the battle. Longswords also made up a large portion of the UNSC's encircling action, cutting off Covenant fleets from reinforcement and destroying them one by one.

Role
As a Fighter, the Longsword was a craft that primarily focused on attacking and defeating other air/spatial targets, such as aircraft, exo-atmospheric single ships and enemy capital ships. While it was capable in a secondary role of ground attack, and was just as capable as its predecessor in this role, in reality it leaned more towards an air/space superiority starfighter, whose role it was to defeat enemy air/spacecraft and attain air superiority. This was resultant of its ground attack abilities being secondary to air-to-air combat, as the F/A-361 Scythe-class Interceptor was more focused on ground attack (but was similarly multi-role). The F-352B Longsword's primary role was engaging and defeating Covenant single ships, in both atmospheric and exo-atmospheric conditions. In addition to this, it could as a secondary role directly attack enemy warships and ground targets with reasonable success, lending itself to a multirole fighter designation. Most commonly deployed to directly counter Covenant spacecraft such as Seraphs and Banshees, its powerful and variable loadout, coupled with its compromise between speed and armour plating, enabled it to be used against a more diverse group of targets. As a result the Longsword was also tasked with ground attack missions, acting in support of allied ground units to defeat armoured threats. With a variable weapons loadout, the Longsword could be deployed against Covenant naval ships, usually after destruction of its single ship defences, using high yield conventional or nuclear munitions. This was particularly useful in downing a hostile vessel's shields, ahead of follow-up attacks by more capable UNSC assets. The Longsword was also regularly deployed as protective escort to either warships heading into a battlezone, or smaller craft assaulting a planetary body or hostile capital ship. When participating in defensive actions around a UNSC planet, the Longsword was launched from both existing ground-based facilities and present UNSC warships. Due to the craft possessing no internal slipspace drive of it's own, the Longsword was deployed into offensive action far from UNSC territory solely from UNSC warships, many of which carried large numbers of Longswords in their onboard single ship complements.

Layout and Flight
The F-352B, like its predecessor, featured a highly unconventional airframe dominated by its' arrowhead shape. Protruding from its highly backswept leading edge was its cockpit section, where the three crew were positioned. From the rear of the craft protruded two oversized engines, on either side of a large tail. With a large surface area, the Longsword featured dozens of control surfaces which, in conjunction with RCS points (Reaction Control Systems) and intuitive fly-by-wire systems, maintained the large craft as an agile one too. While the exterior of the Longsword was virtually identical to the F-352A, its interior was entirely different. The 120mm ventral cannons and their ammunition stores of the were removed, and replaced with two internal, retractable hardpoint bays. The formerly expansive interior corridors, cryo tubes and weapons lockers were all removed, the space instead used for improved reactors, internal shield generator, Covenant-derived inertial compensators and additional space consumed by the internal weapons bays.

The Longsword's highly unconventional airframe lent it a 'relaxed stability' in flight, meaning it was less stable than more traditional designs. The Longsword was unstable to a point where computerised 'fly-by-wire' or FBW systems were necessary to keep it in flight. The FBW system artificially created stability in the Longsword's flight using precision adjustments, allowing it to remain stable despite its inherent instability. The advantages of this instability were extreme agility in both high speed (hypersonic) and low subsonic speeds. The FBW system was quadruple-redundant, preventing catastrophic incidents stemming from FBW failure, and was highly intuitive in simultaneously following the pilot's inputs and maintaining a controlled manoeuvre. As a result of this system, the F-352B was notably more agile than its Covenant counterparts both in and out of atmosphere. The effectiveness of the craft was markedly increased when an Artificial Intelligence was present, as it functioned as a sort of interface between the pilot and fighter (more efficiently than the FBW interface did).

Primary Armament
The F-352B Longsword's primary armament was a pair of M9109 Autocannon, which were similarly employed with the F-352A. These large calibre, high rate of fire cannons were surprisingly effective against Covenant shielding and armour and could be used to good effect against most targets including fighters, dropships and ground targets. These cannon typically carried 5,000 rounds each, and were used against close and medium ranged threats in relative terms. As the Longsword was designed for modularity from the start, these cannons could be removed and replaced for another calibre, which involved changing the gun itself and its ammunition feeds. A larger calibre gave the Longsword more firepower but reduced rate of fire and the amount of ammunition it could hold, while the reverse was true of smaller calibres. Swapping out this armament was time consuming and not a routinely undertaken task. Later on in their service, the Longsword saw their cannon replaced by the same calibre railgun, which dramatically increased the range, accuracy and power of the F-352B's main armament. The weapons were recessed into the Longsword's airframe, located on the leading edge of its wings, and concealed behind inward-folding panels when not in use to reduce RADAR cross-section.

The F-352B could accept the following weapons:


 * M3706 Autocannon- The M3706 was a belt-fed rotary cannon with an extremely high rate of fire. This made it reasonably effective against hard targets in addition to lighter threats. Equipping a Longsword with the M3706 gave it substantially better rate of fire but reduced its firepower per hit.
 * M3911 Autocannon- The M3911 was a 30mm belt-fed cannon that was commonly used as a lighter alternative to the standard 50mm gun. This increased the rate of fire over the 50mm cannon as well as the overall ammunition capacity, but reduced damage per hit as a result of its decreased calibre.
 * M9109 Autocannon- The standard primary armament of the Longsword, the 50mm M9109 was a compromise in terms of ammunition capacity, rate of fire and damage, making it the most commonly used primary weapon. The M9109 accounted for more than 60% of primary weapons utilised by the Longsword, a reflection of its balanced nature that made it the most effective weapon for the F-352B.
 * M4421 Cannon- The M4421 was a 90mm heavy cannon that could be mounted as the Longsword's primary weapons. Though it had considerably increased firepower compared to smaller calibre guns, its rate of fire was substanially lower and it could overall hold a smaller amount of ammunition.
 * M1105 120mm Cannon- The M1105 was a 120mm heavy cannon that was compatible with the Longsword. As with the M4421, it benefited from higher damage dealt as a result of its larger calibre, but saw a drop in rate of fire. Although powerful, its negative aspects made it less effective in combat than the 50mm calibre and was far less popular.

In 2578 the Longsword underwent a lethality upgrade program, among other things updating its weaponry to new railgun-based weapons. The range of cannon available to the F-352B was similar although overall much more effective as a result of increases in muzzle velocity, range and accuracy. With the introduction of railguns, smaller calibre main weapons became more popular; they had the advantages of a smaller round (rate of fire, ammunition capacity) while maintaining damage qualities similar to much larger calibre conventional, chemically-propelled weapons.
 * XM490 30mm Railgun
 * XM502 50mm Railgun
 * XM511 90mm Railgun
 * XM521 120mm Railgun

Secondary Armament
The Longsword's secondary armament was a variable load of guided munitions, stored in two large hardpoint bays that stored missiles in a cylindrical fashion, and retracted into the ship's hull when not in use. These made use of space freed up by the removal of both the F-352A's 120mm cannon and most of the ship's redundant internal space. These hardpoint bays could be fitted with a variety of ordnance, allowing the Longsword to fulfil many roles with very little effort, giving it an additional versatility over the original Longsword. These launchers deployed through two hatches on the ship's underside, either side of it's central 'spine' and between the engines. These could hold a variable amount of guided munitions depending mainly on their size and combination, and could be easily configured for all standard UNSC ordnance.

The Longsword could hold ordnance as follows:


 * Medusa-II Missile- (16) The Medusa-II was an update of the Great War-era Medusa Missile. Designed for launch from small mobile platforms such as starfighters, it was most effective against Covenant single ships such as the Seraph-class Starfighter, being capable on most occasions of destroying it with either a direct hit or a close proximity detonation. The Medusa-II featured several homing systems to prevent it being jammed by enemy countermeasures, and an advanced HEAT tandem warhead with kinetic energy penetrator. This was most effective at destroying targets with a direct hit but could heavily damage them even with a near miss. The Medusa-II featured both contact and proximity detonation systems, meaning it was more likely to damage a target that was taking evasive action.
 * Scorpion-IV Missile- (10) The Scorpion-IV Missile is an updated iteration of the earlier Scorpion-II Missile. Operating exclusively as an air-launched ground attack missile, the Scorpion-IV was a hypervelocity contact/proximity detonated missile; although lacking in agility, its speed and high accuracy virtually guaranteed a direct hit against slow and medium moving ground vehicles and stationary structures. Using the same tandem HEAT/kinetic energy penetrator warhead as the Medusa-II, the missile featured multiple types of both primary and backup target acquisition sensors, enabling it to thwart most active and passive countermeasures.
 * Longbow-XII Missile- (8) The Longbow-XII Missile was a small antiship missile designed for launch from fighter-sized platforms such as the Longsword. The Longbow featured a comparatively small thermonuclear warhead, although it was encased in a lithium triteride shell, which magnified the blast hundreds of times and gave it strength roughly half that of the much larger Shiva-class Nuclear Missile. The advantage of this was that it allowed a single ship to carry munitions capable of more than just denting Covenant vessel's shielding and armour.
 * Shiva-class Nuclear Missile- (1) the Shiva-class Nuclear Missile was a starship/starfighter-launched missile with a variable yield thermonuclear warhead, designed primarily for antiship purposes. The power of the weapon was such that a direct hit would disable a fully protected CCS-class Battlecruiser's shields and deal moderate damage to its hull. Although rarely deployed from Longswords, its extreme firepower lent them an optional tactical advantage when facing Covenant warships.

Shielding
The F-352B was designed relatively shortly after the Human-Covenant War, and not long after the Sangheili agreed to share technology with the UNSC. As a result it was one of the first mass-produced Human-designed vessels to feature Covenant technology, featuring protective shielding and inertial compensation systems. Although cost initially prevented the Longsword from receiving shield generators, a later update provided this among other upgrades. While not comparable in strength to the shielding employed by larger warships, its strength was on a par with that of the Covenant's Seraph, protecting it from a fair volume of fire before actually exposing the Longsword to harm. The shield envelope conformed tightly to the ship's hull, minimising surface area and therefore maximising strength.

In terms of armour, the Longsword was comparatively well armed for a starfighter, featuring multiple layers of strong, resistant yet lightweight materials that lent it increased resilience to both directed energy and conventional weapons. The Longsword's armour, like many of its integral systems, was modular, allowing for damaged armour to be removed and replaced, appliqué armour to be added or base armour removed to reduce weight.

Outer Layer
The outer layers of the Longsword's armour were focused more on withstanding plasma attacks, with lower layers offering anti-plasma and anti-ballistic protection. The outer layer of the armour was an energy-ablative superconductive layer composed of variable property energy-reactive regenerative nanomaterials. This nanomaterial absorbed most of the energy from plasma assaults and used it to increase its own strength, its properties changing according to the amount of energy it recieved. This technology was an evolved form of the plasma-refractive coating used on MJOLNIR Powered Assault Armour, though benefiting from advanced metameterials to turn incoming energy attacks into a defensive ability. As a result the Longsword was able to survive a direct hits from comparatively heavy plasma weapons and remain operational.

Modular Armour
Underneath this somewhat unconventional armour was more traditional alloy/composite armour, which provided excellent protection against ballistic and plasma weaponry. This protection used both modular and fixed armour to provide light weight of transport, while still offering full protection from battlefield threats. Though designed as primarily to counter kinetic energy threats, it had excellent chemical energy protection qualities that were further augmented by the implementation of fifth generation captive ERA. It was also considerably more resistant to plasma attacks than previous composite armours.

The outer layer of the composite modular armour assisted in holding the outer armour together, and allowed some slight flexibility yet superior density to engage various threats. Resin impregnated Aramid fabric was wrapped around the composite armour to allow the best protection and structural strength. Below the outer layer was the primary KE and plasma defence, a single piece poured Ceramic DCP plate.

The Ceramic Plate was sandwiched between two plates of CVT (Chromium Vanadium Tungsten) and Austenic Steel alloy. The whole assembly then underwent a hybrid DCP/Triaxial-prestressing method in which the preformed, porous ceramic material was soaked in a bath of molten metal, resulting in super-dense material. As the metal cooled the composite of three plates (one of ceramic, and two of alloy) compressed, increasesing both the density and compressibility of the composite dramatically. This process worked at relatively low temperatures and therefore was more economical than previous production methods. The resulting compound could be molded into complex shapes and offered improved protection at significantly lower weight. This by itself was rather effective but was supplemented by several other materials.

Below the outer plate were several overlapping ceramic 'chevrons'. These chevrons forced any round that was able to penetrate the outer plate to then penetrate the chevrons at a much higher oblique angle than the outer plate. This increased the armour's effectiveness not only by changing the penetrator's vector, but by increasing the thickness plasma had to penetrate. These chevrons were suspended in an plasma-resistant elasticised rubber-like polymer that reduced the shock to the overall plate and transferred much of the impact energy outwards, reducing the stresses on the impact plates. it was also capable of reflecting or absorbing much of the damage caused by directed energy weapons. This material also helped break up penetrating HEAT jets and KE penetrators by causing the chevrons to move around under the force of impact and degrading its overall performance.

Backing the composite matrix was a second composite Alloy/Ceramic plate forcing the plasma or penetrator to again punch its way through at a different vector, forcing the round to fold or break up before it can defeat the final plate. The whole composite was then sealed in a wrap of plasma resistant treated aramid fibres to absorb any remaining spall or plasma splash and attached to the base armour of the Longsword's hull in sections for easy replacement.

Base Armour
The 'Monolithic Armor Plate' (MAP) for the F-352B was produced using a process in which sets of inexpensive, thermodynamically compatible ceramic powders (Boron Carbide (B4C) and Titanium-Carbide (TiC)) were blended with thermoplastic polymer binders and then co-extruded to form a fibre. This fibre composite was first braided then woven into the shape of the desired component. The fabricated component was then stacked and pyrolysed to remove the polymer binder and hot-pressed to obtain the base preformed ceramic material for final processing.

The preformed ceramic matrix was still rather porous, and though extremely hard and ductile, was still rather fragile compared to a composite plate. The DCP process avoided extensive shrinkage in the processing of dense ceramic parts, worked at lower temperatures than conventional methods, did not require the use of high pressures and eliminated the need for post-process ceramic machining. The preform was then soaked in a liquid metal alloy bath. The preform absorbed the liquid metal like a sponge; the liquid metal then reacted with the ceramic powder to form a new ceramic compound that filled in pore spaces. The result was a part with a larger internal solid volume, but the exact same external shape and dimensions as the original preform. The DCP method required reaction temperatures of only 1,300C, compared to the 2,000C required for traditional methods, to form very high melting point, covalently-bonded ceramics. Because the final part maintained the shape of the original porous ceramic, post-process reshaping was eliminated. This translated to cost savings for manufacturers, allowing for more armour to be produced.

The finished Composite was extremely dense, lightweight and ductile enough to resist severe impact stress, while providing excellent anti thermal, kinetic and plasma properties and being easy to manufacture and replace when installed in a modular system.

Engines and Powerplant
The main engines of the F-352B were two linked Mark XXVIII TEMPEST Fusion Reactors. Here, atomic nuclei fused to form a denser nucleus, accompanied by a net gain of energy. These reactors jointly provided energy for the ship's systems; additionally the fueled the engines by expelling confined plasma at super-high velocities, producing thrust. These engines had exceptional thrust and acceleration, though the craft's top speed of 318,960 kph (Mach 267) was rarely reached in combat. Its speed and agility, though more the former, were substantially affected in atmosphere, although it still maintained its effectiveness. The engines were capable of vectored thrust through numerous control surfaces manipulating the exhaust flow, making up an aspect of the craft's FBW systems and contributing to its agility at both low and ultrahigh speeds.

The Longsword made use of dozens of control surfaces on its exterior to manoeuvre in atmosphere, though they were useless in spatial environments. These, coupled with dozens of RCS points that made the F-352B capable of both taxing manoeuvres and microajustments, helped the Longsword maintain staggering maneuverability for a craft of its size.

The F-352B also operated Covenant-derived inertial compensators, which negated the effects of extreme g-force on crew and enabled them to perform acceleration and manoeuvres previously unheard of. It also effectively reduced the craft's weight somewhat, improving acceleration and other performance characteristics.