DY class (Delta Dynamics)

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Note: the image and the stats depicted in the sidebar represent the DY-100 interplanetary transport, the most numerous type within the DY sublight vessel series.

The following is a summary of the development of DY series of sublight and warp vessels over the Playground (pre-2063) and Incredible Expansion (2063-2130) periods. For more complete details, please access the relevant reports (links below).

Sublight types[]

DY-50 Experimental Transport[]

DY-50 et 3-ortho — The Chinese-adorned DY-50 experimental transport

The Dinyan-Yoyodyne Conglomerate was one of the most public representations—though not overtly so—of the enhanced intellectual capabilities of the Augments. It burst on the scene with a massively heavy and reusable lift vehicle (the DY-T) and two experimental heavy space craft (the DY-50), as test platforms for a full series of vessels that would quickly overshadow the achievements of the Americans’ 10-year-old orbiter fleet. The craft were fueled by a liquid hydrogen-oxygen propellant, mixed with a proprietary compound that significantly reduced oxidation while also increasing chemical reactivity, providing a thrust exhaust ratio—in a reaction engine that was also proprietary—that far exceeded any system manufactured elsewhere on the planet. The launch of the two vessels in quick succession from China’s Wenchang Launch Center shocked the other space-capable nations. Such a heavy craft launching to orbit with such a non-aerodynamic frame, more akin to a submarine than a launch vehicle, with such a small propellant section seemed simply impossible, yet it had been done. Yes, the craft could not get any further than low earth orbit at launch, but—equally amazingly—the automation of the DY-T rocket that had launched only 24 hours earlier provided all the necessary fuel for the first DY-50, the Shuguang (“Divine State”), to achieve high earth orbit (HEO), far in excess of any previous manned vessel not on a cislunar trajectory. As the Shuguang returned to LEO, the Shenzhou (“Divine Ship”) launched, refueled, and proceeded to complete a full cislunar flight path, with 4 orbits of the satellite, before also returning to LEO.

Neither ship could return to the surface of the planet, but they demonstrated a capability that had not existed outside of forty-year plans the more capable space agencies were only preparing. The ability to send a manned vessel to the moon at a delta-vee of 0.005c (~5,400,000 km/h) was quite simply earth-shattering. Over a period of mere weeks, concepts of lunar & Mars outposts, asteroidal mining, and even manned system exploration were advanced by decades. And despite the catapulting of the Chinese from a space-envious status to the premier space nation on the planet, Dinyan-Yoyodyne was not locked into that nation as its sole client. A production schedule was quickly and easily reached with the Indian Space Research Organization (ISRO), the nascent Korea Aerospace Research Institute (KARI), and the United States Air Force. Other nations held back, reticent to sign on to what was still (possibly) a dubious enterprise, then began rapidly investing in infrastructure that other organizations and corporations (most associated in one way or another with what would be identified as the Great Khanate) stepped up to provide. South America, Europe, Oceanic nations, and numerous regions of northern Africa began sprouting factories, laboratories, and training facilities to support the suddenly all-growth space industry. Craft production centers were built in India and the United States, with the Wenchang facility also exporting completed spacecraft for South Korean and other Eurasian use.

The DY-50s themselves remained active experimental platforms even as the first DY-100s launched onto their own missions a year later. The ships never hosted more than 4 Humans, and that only during crew turnovers, as they were very limited on creature comforts and life support. Unlike the later transports in the DY series, the ship never had the capacity to haul the familiar Type DY standardized cargo module, as it was only intended to prove the heavy launch vehicle concept. It did have an internal capacity for over 1,400 metric tons of cargo, accessible from a rudimentary area on the midsection, behind dorsal clamshell doors. Another difference between the DY-50 and later ships in the series was the interplanetary drive. Unlike the DY-100 and its succeeding classes, this CALT-Z5 drive section was a permanent installation. Those first launches in 1989 proved the hypothesis that the production ships would need one propulsion system for achieving orbit and another for transiting away from Earth. The Shuguang and Shenzhou would perform many Earth-Lunar flights, first as mission tests, and later in reconnaissance flights of potential landing zones on Luna. However, by 1991, the DY-Ts were no longer routed to the orbiting vessels for resupply services and at the end of the year, the final crews departed via the emergency escape capsules. The ships were maintained in stable orbits for another three years, before being de-orbited by automated routines on vectors to Earth’s spacecraft cemetery in the South Pacific Ocean Uninhabited Area.

DY-100 Interplanetary Transport[]

DY-100 (unladen) 3-ortho — Unladen DY-100 interplanetary transport

In what would appear to have been a bit of brilliant marketing by Dinyan-Yoyodyne to demonstrate its open-market nature—in light of the sudden awareness of Chinese launch technology with the DY-50—the rights to the first DY-100 interplanetary transport were sold to the ISRO in 1989. The sale of the Sahasrara (Hindi for “Thousand Petals”) to the Indians was the kernel of a revolutionary business concept, where space was an international “sandbox” for commercial purposes, without the decades of intergovernmental competition that had stifled near-Earth development. Similar sales were made to the United States and South Korea, with their own ships being delivered in 1991 and 1992, respectively, following China’s own acceptance of the second and third vessels to be built. Between 1989 and 1996 (when the Great Khanate fell, taking most of Dinyan-Yoyodyne’s proprietary production facilities with them), 7 DY-100s (known as Kaitòuzhe) were built for the Chinese, 2 (Iskra) for the South Korean’s KARI, 4 (Vayu) for India, and 6 (Copernicus) for the American air force. The Great Khanate reserved one for their own use (built in 1994), for a total production of 20 first-run interplanetary transports.

With the initial vessels, the launch booster would be detached upon achieving orbit and allowed to burn up in the atmosphere. The ship would maneuver, on RCS thrusters, to mate with the DY-B series interplanetary drive—delivered to a shared orbit previously by a DY-T heavy launch vehicle—providing the DY-100 with the massive and capable fission power systems installed within the module. At this point, the 12-person crew had a complete vessel on their hands, with any destination within 6-months travel a possibility, and capable of achieving 0.01c, given enough time for acceleration and a minimum mass load. Most vessels engaged in early exploration and construction missions to Luna or resource scouting in the Main belt. In either case, the ventral bay on the bow of the DY housed an auxiliary craft appropriate for the destination: the lunar lander, reminiscent of the previous Apollo series (but fully capable of lunar surface launches), could carry 2 crew and 2 passengers to the surface. The asteroidal landers had grappling hooks on winches, to assist the minute but precise chemical thrusters in getting the miners secured to their target. Specifically for early lunar base construction tasks, the DY would deliver a lunar tug in place of one of the sixteen cargo containers; the tug was capable of delivering 4 of the containers to the low-gravity lunar surface. The tug would remain behind, shuttling cargo up and down between the base and future visiting transports.

Details on the final dispensation of the DY-100s are sparse, due to the extreme violence and levels of destruction the planet would suffer over the coming decades. “Salting the earth” was a repeated practice by the Augments when they saw their individual domains rapidly slip from their fingers, with the DY ship production facilities destroyed decidedly and with little chance of immediate recovery. This would set the Humans’ interplanetary capabilities back to almost 1988 levels. The scientists of Delhi had just perfected the first practical long-term cryogenic sleep technology to allow “safe” use by living beings; however, this went unannounced in the growing chaos, with the early achievement only realized when the SS Botany Bay was discovered lightyears downrange in the Mutara Sector, 270 years later. The remaining first-run DY-100s would serve various roles—generally military in nature—close to Earth, as the various competing nations seized what Dinyan-Yoyodyne assets they could.

It would not be until 2021 when the series re-entered production. Russia, the core member of the Eurasian Confederation, had uncovered D-Y production plans for the spacecraft in Baikonur two years previously, and ramped up the Eurasian Confederation Space Agency’s production and launch capacities precipitously. China was provided the plans in a trade agreement and by 2023, the United States—working with D-Y offshoot Yoyodyne Propulsion Systems—had them as well. No later than 2028, China had 5 additional DY-100s, the United States 12, and the ECSA operated 21. Ground-based production of large spacecraft had transitioned to the various space platforms in orbit of Earth, positioned at the trailing L-5 point, or above Luna and the less gravity-restrictive conditions had seen the introduction of vessels either directly descended from the DY-100 series, or working off entirely independent design concepts.

DY-110 Apex Mission Spacecraft[]

DY-110 Apex ms (unladen) 3-ortho — Unladen DY-110 *Apex* mission spacecraft

The most that can be surmised regarding the intent for the DY-110 Apex mission spacecraft is the twelve ships were intended to actively progress the Great Khanate’s interplanetary agenda, which itself can only be theorized as to dominate non-Augment Humanity and push the species onto the interstellar stage. Few records exist to detail what the Apex took part in; only the ship names and destinations are available as complete documents. Naval historians naturally used the comparative method as a means of teasing out the truth: in what ways was the ship different than the DY-100 on which it was based? Very similar in silhouette, the Apex had a slightly more streamlined look on the conning tower. Most striking was the midsection: where the DY-100 had adhesion plates to accommodate 16 DY-style cargo pods, the latter vessel was limited to a maximum of 5. Instead, the forward dorsal pod space, as well as the aft 8 connections, made way for added craft superstructure that included about 16 more meters of length. These additions only saw a surprisingly meager 80 metric tons to the overall vessel’s dry mass.

To be certain, the crew size was doubled, and—as is understood well after the period of the Eugenics Wars—they were all Augments. A radar-controlled missile launch tube, loaded with 10 fragmentation warheads, was installed at the forward base of the tower and a space-modified defensive close-in weapons system—with 2,000 high-explosive rounds—deployed from a hatch on the mid-section, above the cargo pods. The vessels did not appear to be equipped with cryochambers; only Botany Bay was proven centuries later to have that technology. The Apexes never even ventured out as far as the Main belt, limited to round-trip voyages from Earth to Mars or Venus. Those voyages were prolonged by undecipherable loiter times on station to do what? Build permanent presences seems the most likely answer: it was Augments who first stepped foot on Mars in late 1993, immediately setting forth not on exploration, but the construction of a surface base and adding long-term features, such as a large fission plant.

DY-110 Apex ms (5-laden) 3-ortho — Fully loaded with 5 cargo pods

Manned Venus landings were, very surprisingly for the technological capabilities of the time, conducted in 1994. Unlike past Human endeavors, the Augments did not publicize either of these historic achievements, but did confirm them when their rumors were reported upon weeks later. However, maybe the Venusian landings can explain the modified form of the Apex, because there is little doubt the landing craft could not make a second trip to the surface without a tremendous degree of overhaul, as the excessive heat and crushing atmospheric pressure would take their toll. It is possible the ships had workshops that provided the overhaul capacity.

Two of the three ships that were in Earth orbit during the fall of the Great Khanate were destroyed in the attempt, while the last was so damaged in its escape that it could not decelerate upon its arrival at Mars, devastatingly impacting the surface at speed. Five maintained their positions above their respective planets (2 above Venus, 3 Mars), until well after the capability to support human life had passed, also eventually succumbing to destructive orbits as late as 2008. The remaining four never returned to Earth and it is presumed they were lost at any of a number of places, possibly including the Main belt.

DY-120 Brenton Rescue Cutter[]

DY-120 Brenton ms 3-ortho — ISA DY-120 *Brenton* mission spacecraft

Previous space agencies, in utilizing the DY-100s and -120s, had developed national agendas for their national assets, some of which dovetailed a little too nicely with some corporate agendas, while others—such as the ESA and NASA, did endeavor to use them not only for building orbital structures and industry, but also exploration and science. However, it was the ISA, founded by the New United Nations (NUN) in 2018, that saw a looming demand for a vessel to be used for search and rescue (SAR), as well as law and regulation enforcement. Subsidized not only by the NUN, but also corporations and nations that recognized the wisdom in being able to recover their expensive assets—and their spacefarers, of course—Yoyodyne assembled, starting in 2023, a variant of the civilian DY-120 transport for the ISA.

The first and most eye-drawing feature of the Brenton were the 18 bright-red Type T fuel cells adorning each perspective of the vessel. Just as with all other interplanetary craft preceding it, the SAR ships relied on the slow-but-faithful ion thrusters to achieve maximum range at considerable speed; however, due to the nature of their mission, the reaction control thrusters saw considerable use—even over-use—as the ships maneuvered within “walking” range of their target vessels, or otherwise negotiated around an obstacle or away from a particular threat (such as debris). The thrusters required reaction chemicals and had to be relied upon to operate when required. The T-cells provided in excess of 55 multiples of the fuel amount a standard transport could expect to use between destinations of call, but—statistically—only about 4 times what a Brenton would use on a patrol.

Another significant difference between the civilian DY-120 and the Brenton was the cargo pods: it had none. Instead, what appeared to be 15 DY-type cargo containers was one entire unremovable superstructure, with an added “cap” over the dorsal midsection serving as the equivalent to another manned deck. This structure provided the operational capability via mission spaces set aside for rescue and salvage equipment, additional storage for replenishment oxygen, berthing (and a brig) for rescued spacers, and common spare parts for vessels that just needed that “one” component in order to be mobile and on their way again. The midsection spaces also included a total of six cargo bay doors, four for typical pod access, one large one for oversize equipment, and a dedicated pod-sized hatch directly adjacent to the ship’s enlarged sickbay. The port and starboard would each have three re-chargeable light-scattering glass bead emitters added as defensive measures, when laser weaponry started to be encountered not only on military craft, but also on civilian ships that might not take too kindly to a ship of the law. The electronic counter measures systems expected of a militarized vessel were mounted on a steerable pod installed ventrally just aft of the bow, with an electronic counter-counter measures suite providing a nearly 360/180 degree field of view situated on top of the conning tower. The shuttlebay typically found within the bow of a DY-series was replaced by additional avionics and communications gear.

DY-140 Helsinki Rescue Cutter[]

DY-140 Helsinki ms 3-ortho — DY-140 *Helsinki* mission spacecraft

In late 2037, the ISA grandly announced the full funding of 12 yet-undeveloped future search and rescue vessels to gradually replace the aging and well-worked Brentons. Additionally, the contract provided a partnership with YPS that would jointly design a line of vessels continuing from the mission spacecraft production run into a commercial passenger transport utilizing the exact same hull and engineering layouts, loaning the prestige and confidence of the ISA to the ship builder. To the world, the NUN was proclaiming that it had enough faith in YPS—despite the very public blow to the company’s design reputation—to rely on a future DY series vessel for its astronautical safety agency and the lives of spacefarers throughout the inner system.

The investigation into the shiphandling failures of the commercial DY-130 transport very clearly shined a spotlight on two major contributing factors: the inadequacy of the reaction control system for a vessel of that size and the chaotic center of mass problem associated with hauling large individualized containers of asteroidal ore. With those issues in mind, the DY-140 Helsinki was built around the traditional submarine hull of the DY series with an extended structure—alluding to but not indicating actual standardized cargo containers—from the ventral and wrapping partially up along both sides. This provided additional work, living, and combat system spaces for the vessel, without allowing too much emphasis on cargo hauling capacity. The ship made use of a much more powerful ion reaction drive, necessitating a nozzle-like radiation barrier that guided the more dangerous particles astern.

Defensive weapons were limited to the standard glass beam emitters, four running along both sides of the hull extension with an extremely long emitter along the ventral; this provided a rather broad emission “curtain” when deployed. Ship commanders were instructed to focus their initial protective actions with the activation of this emitter first by rolling the ship, essentially creating a shimmering spectacle of laser-deflecting beads that confidently demonstrated the ineffectiveness of any anti-ship laser usage. The smaller emitters were secondary in nature, reserved for the time-intensive reloading period of this main bank. Offensively, the Helsinki was well-prepared. Three Roosevelt system rail guns, each with 25 rounds, extended from the cowl structure. Laser systems were initially considered, but it was felt too many turrets would have to be emplaced about the hull to be effective in the present era of reflective armor and anti-laser glass shield systems, and that would make the vessel more of a gunboat than a force for peace. The rail guns were also seen as rather provocative in their brutish presentation, but heat and size limitations prevented them from being any more embedded within the ship than eventually established. The use of three was also a debatable point, but in the end, it was decided that the long reload period and relative undependability of the systems meant having “one more” would be justified if one was already down for maintenance or repair when action was deemed necessary.

DY-135 Black Mamba Regulatory Cutter[]

DY-135 Black Mamba ms 3-ortho — DY-135 *Black Mamba* mission spacecraft

By the time Yoyodyne Propulsion Systems was completing its first production run of their commercial DY-130 interplanetary transport (with the SS Black Mamba), the vessels' story appeared abruptly completed. Maersk had encountered several ship maneuvering problems from the immediate operations of their three ships: when even partially loaded, the reaction thrusters were proving incapable of maintaining positive control of the ship’s flight profile, most notably when approaching loading and unloading stations. A few allisions with minimal damage occurred in 74% of restricted maneuvering operations in the first 10 months alone, with any catastrophes avoided sheerly on the experience of the ships’ crews. Maersk threatened to sue for release from their 15-year contract and all interest from other commercial sources dried up within a few weeks. The ISA, operating under the mandate of the NUN, investigated. While their primary concern was in regards to the safe operation of spacecraft, they were equally concerned with the future of Yoyodyne, an otherwise trusted and critical shipbuilding partner for the agency and other governmental operations. During the investigation, the reaction control systems were proven to not only be extremely under-powered for the mass of a loaded ore hauler, but also poorly placed to handle a shifting center of mass problem, a common issue for loose ore under a dynamic speed delta. The two solutions—refitting an entirely new series of thrusters or redesigning a much smaller cargo component—were just not feasible, especially for a class of ship that had already been identified as a disaster-in-waiting. Instead, with a corporate-saving contract from the NUN, Yoyodyne Propulsion Systems went back to the drawing board to design a new interplanetary vessel, based upon the inquiry’s results. The ISA would guarantee the safety of this class (the DY-140) by being the first to take receipt of 12 vessels for modernized search and rescue missions.

However, that was not the end of the DY-130. The ISA, working with Yoyodyne, took possession of the Black Mamba and began a fully-subsidized refit that would incorporate the investigation’s suggestions of relieving the ship of its enormous and unstable cargo load and redesigning the thruster system. In place of the enormous Series Two container pods, a much less massive and permanent semi-circular superstructure was added onto the main hull. Though not as extensive or internally large as the same structure on the aging DY-120 Brentons, the six repurposed vessels did have two hatches for repair equipment and cargo access, an adequate medical bay, emergency quarters for rescued spacers, a ventral hanger bay for 3 Class A3 “Zent Mark II” EVA pods, and 8 Type T fuel cells.

For all intents and purposes, the ISA seemed to have designed itself a modernized search and rescue craft, but one that paled in comparison to the DY-140 Helsinki class that had debuted three years earlier. Instead, the six Black Mambas performed as up-gunned law enforcement vessels (in another of the ISA’s wide net of mandates), helping ensure that the small corporate flare-ups between asteroid miners or the smuggling/piracy operations of struggling independent tramp freighters, was kept in check. The DY-135s sported what was hoped to be a completely unnecessary Mark II nuclear missile launch system, with 36 warshots, and 4 forward-firing prototypes of the forthcoming Sorac 0.36, a 90-megawatt laser emitter that outclassed any other medium-powered spacecraft-mounted laser systems. While the prototypes proved to be about 20% larger than would be produced just six years later, and generated an enormous amount of heat, they could cause a respectable amount of destruction upon any spacecraft hull, as was very publicly demonstrated upon a target meteoroid of not insignificant-size.

Due to the tensions between the ECON and the Western Alliance-dominated NUN, the Black Mamba craft proved to be problematic due to their existence alone. The mounting of such overpowered lasers might have been forgiven in a law enforcement role, but the inclusion of nuclear weapons on the vessels proved ECON fears that the post-Swarm militarization of space was a credible threat to their interests. Regardless of the limited numbers of the mission spacecraft and despite its troubled origin, the ISA’s police vessels were consistently tracked and reported by all ECON-affiliated vessels as potential aggressors; anytime they showed up with the intent of conflict de-escalation, ECON defense forces elevated their response alert status. The vessels were priority targets in the infamous days of May 2053.