When the Eridonia Free Peoples' Fleet (also known as the EPF) stood upon its own two feet, establishing a real presence in the shadow of the Aquarius Cluster, it became clear that the 'Rebellion' would need its own, purpose-built warships, to be crewed by the influx of volunteers from the ISAR resistance in the Angel Reach, and worthy candidates conscripted from the populations of Old Bastion Star's own colonies.
By 4450 A.D, the EPF had transformed from a rag-tag collection of Freedom Fighters to an established faction with its own military forces, based out of the Angel Hook Nebula. The first of a series of new Heavy Frigates was developed by the EPF's engineers in Old Bastion Star - based on the now ancient 'Hammerhead-class' Heavy Frigate that had been in service with the Old Federation for more than a millennia before. While old, the hull was extremely reliable and importantly; cost effective to manufacture and deploy. While the EPF's resources were growing each day, supplies were still limited and the first run of purpose-build warships needed to be extremely efficient.
'Heritage'-class is carries the name sake of the original Hammerhead-class Frigate in service with the EPF since its formation. The classification's name pays an homage to the service of that venerable warship and her crew.
Heritage-class was developed to provide the EPF with a fast, agile combat platform with advanced sensors and electronic warfare capabilities, integrated Jump Drive Array and specifically; a fully flexible B-Type hardpoint capable of equipping standardised B-type modular weapon subsystems already being produced by the shipyards at Old Bastion's Star. This was an extremely tall order for even the EPF's talented starship engineering department; and the resultant warship had to make some significant compromises, but largely achieved the primary design goals.
Heritage-class Heavy Frigates are of similar size to the Hammerhead-class they are based on, but significantly more massive. The durable space-frame of the original hull design allowed surprising retrofits during prototyping, with an almost doubling of the power-plant output in electrical potential at almost half the size using the latest HBCF reactor technology available to the EPF engineers. The new reactor is of similar mass to the previous powerplant, but occupies less physical space - with twice the output. Despite the doubling of powerplant output, original Heritage prototypes had significant issues with the main grid being underpowered, with almost all of the new reactor output requiring to be focused to the Jump Drive Array - a module almost only found on larger, cruiser-class hulls throughout Aquarius.
As such, a new power management system was developed specifically for the Heritage-class: The integrated JDA is isolated from the primary grid and requires an extended charge time surpassing that of larger vessels, despite lower mass, due to the huge energy demands on the frigate's internal power supply. This compromise was deemed acceptable as the utility of being able to transit FTL independent of a larger, carrier-type ship was considered almost essential for EPF Frigates operating throughout the Angel Reach and beyond.
The new power management system also allowed a significantly upgraded shielding modulator, at the expense of parallel systems operation; for example, Heritage-class warships are unable to operate the highest level active sensor systems and charge their shield modulators to peak output simultaneously. Furthermore, charging the JDA requires both the Active-array and the shield modulator to be completely disabled in order to operate, leaving the vessel highly vulnerable and unable to make emergency escapes. This wasn't considered a major flaw due to the nature of how Frigate-classes are incorporated into the EPF's naval doctrine; focus on wolf-pack formations and highly flexible, semi-independent escorts for larger warships or civilian craft.
Despite the shortcomings, the Heritage class is a powerful warship able to 'punch above her weight' compared to contemporary frigates of the old UAS Federal Navy, and more comparable in capability to the Aquarian Imperial Navy's newer Eel-class Assault frigates, but with the added flexibility of an impendent Jump Drive Array. This highlights the design choice differences between the Imperial fleet and the EPF; the latter doesn't have the luxury of almost limitless and resources and ship-production capability.
The largest external enhancement of the Heritage's armament, over the Hammerhead-class design is the inclusion of a single, fully flexible B-type hardpoint on the dorsal side of the main stern compartment. The EPF deemed it necessary for their frigates to carry heavy firepower to allow them to engage larger cruisers at medium range when operating in wolf-packs, allowing them to route Imperial Patrol cruisers rather than being entirely unequipped to deal with them. The B-type hardpoint added considerable mass to the design, and contributed greatly to the energy requirements of the JDA; the weapon system and is ancillary systems account for almost 20% of the entire warship's mass. The hardpoint is fully compatible with ammunition based B-type hardpoints of standard design, such as MA-FIMD batteries or FIMD Autocannons. Due to the already overstrained powerplant, Heritage is unable to equip the heavier energy weapons such as the HAL series of Laser Cannon turrets due to the power requirements and strain on the power / capacitor distribution grid. However, she is able to utilise Solid State Laser Cannons with battery-capacitors if required.
The standard armament of the Heritage-class Heavy Frigate is a new weapon system designed by the EPF specifically for this platform, on the B-type hardpoint; the 'Archer' Missile System. Not an entirely new design, but based on project upgrades and enhancements to existing 'Hornet' missile systems that are widely deployed in almost all warships in Aquarius to some degree, but integrating a new, medium to long-range guided anti-capital ship missile system onto a flexible turret with self-contained targeting systems. The development of the Archer Missile Turret goes beyond just deployment on Heritage-class frigates, and is expected to compliment the HAL2/3 turrets deployed on most EPF Cruisers and Capital ships Currently. Archer would allow a high-impact long range anti-capital ship armament to be installed on a B-type hardpoint, allowing smaller ships to carry vastly increased firepower.
Although almost every aspect of the hull was touched upon, the last major upgrade was to the drive systems. EPF Engineers were challenged to upgrade the drive output inertia to compensate the almost 50% increase in mass, within the same size physical drive package. Upgrades to helium-fusion plasma recycler technology allowed for around 20% more drive inertia, but engineers ultimately achieved the same mass/force ratio as the Hammerhead by adding an upgraded cooling system under the ventral side of the rear compartment, with a pair of hardened solid-state radiators containing synthesisable liquid oxygen coolant to be exposed to the vacuum of space, venting heat build-up within the drive system and allowing a higher peak output. Due to the way drive plasma is recycled from operation of the HBCF reactor, the ship's drive output is largely unaffected by the new power management system, potentially even allowing further reactor output by venting waste helium plasma into space via the drive nacelles; increasing the speed of the ship during heavy loading.
Overall, Heritage-class is an ambitious design that attempts to incorporate many modules reserved only for cruiser-sized vessels and above, into a flexible frigate-class platform without compromising its mass/force ratio. Despite some compromises, EPF Engineers largely believe the design to be a success and Heritage-class frigates are expected to undergo first production runs by the middle of the 45th century.