Combat Frame Data: XCF-026 Grenzmark IV

Model number: XCF-026
Code name: Grenzmark IV
Nickname: Grenfour
Classification: prototype multipurpose high-speed combat frame
Manufacturer: BEC
Operator: UCP, MRV, PAX
First deployment: CY 99
Crew: 1 pilot in panoramic cockpit in chest
Height: 19.5 meters, 21 meters with outboard winglets
Weight: dry weight 64 metric tons, full weight 83 metric tons
Armor type: aerographene-infused titanium foam
Powerplant: x2 cold fusion reactor, max output 1600 KW each
Propulsion: integrated variable impeller: 410,000 kg maximum thrust; top speed 6500 kph; 180° turn time 0.40 seconds; legs: top ground speed 194 kph
Sensors: gravitic, radar, thermal, optical sensors mounted under radome “head”
Hand armaments: 80mm Grenzmark autorifle, 180 carbyne-coated tungsten rounds per magazine, stored on back rack, hand-carried in use; gravity axe, stored on recharge rack in skirt armor, hand-carried in use
Special equipment: flight control A.I. (centralized, XCF-026a; distributed, XCF-026b), ion field projector, TC/D drive

As the Ynzu War neared its fifth decade, the mass production One-series XSeeds mankind relied on began to show their age. BEC saw the disastrous Battle of Earth as proof that their flagship MCF-122 Emancipator couldn’t stay competitive on the evolving battlefield.

Browning Corp CEO Jael Red funneled the company’s vast resources into designing their lagging XSeed’s successor. Based on God Emperor Theodore’s suggestion, Jael fast-tracked a resurrected version of the venerable Grenzmark line.

The new Grenzmark initiative caught the attention of CF engineering prodigy Ehud Red. At their father’s behest, Jael grudgingly let her younger brother oversee a side branch of the project. The assistants Jael had tasked with babysitting Ehud instead reported that many of his ideas outshone anything her team had come up with. Jael swallowed the slight against her pride and directed her engineers to steal the innovations pioneered by Ehud’s B team.

Aware that ISBC had first mover advantage in terms of defense with their XSeed Angel King, and the UCP’s Cyclone had cornered the market on firepower, Ehud chose to carve out a new niche for BEC by going for raw speed.

Ehud took the previous Grenzmark model, the CF-016 Grenzmark III, back to the drawing board. To his surprise, he found that many elements of Tod Ritter’s century-old design remained relevant. The key to the breakthrough he sought lay in optimizing their placement. Keeping the classic Grenzmark body style, Ehud stripped out all internal components and started again from the inside out.

In an early masterstroke, Ehud replaced the CF staple main drive-maneuvering thruster combination with a single integrated system. Dubbed the Integrated Variable Impeller, or IV-I, the new EM propulsion system channeled energy from the unit’s core to every part of the CF using superconductive surfaces and wave guides. Though slightly less responsive than dedicated maneuvering motors, the IV-I made up for reduced nimbleness in dramatic weight savings. The resulting system attained performance approaching that of a gravity drive, producing 80% as much thrust as the XCDS-00M0χ XSeed χMetatron.

To meet his new propulsion system’s massive power demands, Ehud kept the original Grenthree generator and added a second. He tweaked both reactors to squeeze every possible drop of power out of them, and installed them in the new model’s shoulders. This touch not only boosted the unit’s total power output, it halved its chances of being incapacitated by a single hit.

With his propulsion problems solved, Ehud moved on to the new Grenzmark’s armament. In another nod to his father, and a further effort to minimize weight, the young genius once again looked back to combat frames’ early days. A variant of the august Grenzmark II rifle was chosen as the new model’s main weapon. Given updated targeting systems, the base Grento rifle was rechambered for 80mm carbyne-clad tungsten rounds and adapted from a firearm to a railgun. The final product resembled the MCF-121 Defender XSeed‘s linear autorifle but boasted 15% greater stopping power and almost double the ammo capacity. The structural reinforcement that enabled the weapon to endure the greater heat and pressure it was subjected to made it heavier. But stress tests indicated the gun could withstand being used as a club.

To head off the need for such a drastic measure, Ehud designed a “gravity axe” as his Grenzmark’s main melee weapon. Collapsible into a curved bar for storage in the CF’s skirt armor, the extended weapon resembled a boarding axe with a chisel-like head backed by a straight, tapered spike. Much like the lances carried by the Coalition’s Einherjar drones, the gravity axe utilized gravitons to weaken the molecular bonds of objects stuck with its blade. A multi-layered carbyne coating allowed the axe to parry plasma blades and even resist energy weapon fire for a limited time.

With such few, though potent, weapons, the new Grenzmark would need to afford its pilot supreme situational awareness. Ehud ditched the standard CF cockpit with its four multi-direction screens placed in front of the pilot. In its place he installed a spherical chamber with super high-definition screens covering its entire inner surface. The chair was placed in the middle, giving the pilot an unobstructed panoramic view. The net effect made test pilots feel like they were flying a chair through space at incredible speeds.

In fact, they soon came up against the novel problem of going too fast.

When simulator runs revealed that pilots had difficulty keeping up with the new Grenzmark’s blistering speed – almost 1,000 kph faster than the Metatron – Ehud realized that special flight assistance measures were needed. He started by adding a pair of winglets to the CF’s generator-swollen shoulders to improve stability. The short wings performed much like canards or strakes in an atmosphere, while in space they served as additional wave guides and EM thrust vectors. This simple addition gave Ehud’s design maneuverability on par with competitors’ Two-series CFs.

Yet the pilot reaction time problem remained. Jael’s team finally scored a coup by implementing an advanced flight control A.I. to assist the pilot at high speed. The solution worked, but Ehud’s studies of the Kazoku War and HALO Conflict alerted him to a potentially fatal flaw: The centralized A.I. would be easy for a savvy enemy to hack.

After all his inspired CF design innovations, it was a software problem that stymied Ehud. While researching old open-license CF designs, Ehud chanced upon the Wild Hunt. The integrated weapons platform featured multiple A.I.s working in concert. It occurred to him that if a handful of A.I.s could work together for proportionally greater results, why couldn’t hundreds cooperate on the same task? Ehud hastened to test his theory. It worked beyond his wildest expectations. The cluster of distributed A.I.s collaborated with each other and the pilot to provide light-speed precision flight assistance, even at the new Grenzmark’s top speed. Even better, hacking the system would require co-opting one node at a time. With the myriad remaining nodes fighting back, only a simultaneous cyberattack en masse could take over the flight control system.

With a blindingly high-performance yet easy-to-handle design under his belt, Ehud applied the finishing touches. He upgraded the Grenthree’s old Halo suite with cutting edge gravitic sensors. Closing the original grills gave the sensors extra protection, but Ehud paid homage to the Grenzie trademark with a set of overlapping “shutters” fronting the CF’s domed head. In accordance with UCP regulations, he included an ion field projector one-third more powerful than a One-series XSeed’s. And in line with MRV doctrine, he made the new Grenzmark TC/D capable.

Upon successful completion of simulator testing, BEC gave both competing XCF-026 designs the Grenzmark IV designation, with a and b variants. Both were originally painted in classic Grenzie olive green, but after allying with PAX, Ehud painted his XCF-026b red for his brother Jehu. The XCF-026a remained in BEC’s hands – and green – while its anonymous test pilot fielded the new unit against the free ExSols to devastating effect.

The white-knuckle dogfights of Macross meet the planet-hopping adventure of Star Trek

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