Guide:Horizon/Advance: Difference between revisions

Horizon/Advance
Class Overview
Category	heavy cruiser / battle cruiser
Operational	2193-2297; Horizon (heavy cruiser): 2193-2219; Advance (battle cruiser): 2198-2219; Whorfin (battle cruiser/survey cruiser): 2210-2297; Indomitable (battle cruiser testbed): 2210-2212; Horizon Flt II (heavy cruiser): 2218-2249; Advance Flt II (battle cruiser):2218-2258; Essex (battle cruiser): 2222-2251; Archon (heavy cruiser): 2222-2263;
Constructed	40 total; Horizon: 13 (built 2190-2199); Advance: 10 (built 2198-2204); Whorfin: 3 (built 2210-2215); Indomitable: 1 (built in 2210); Horizon Flt II: 13 (upgraded 2218-2219); Advance Flt II: 9 (upgraded 2218-2219); Essex: 7 (built 2219-2225); Archon 7 (built 2219-2224);
Dimensions
Length	; 294.1 m (Horizon, Advance, Whorfin, Essex, Archon); 311.8 m (Indomitable);
Beam	; 117.1 m (Horizon, Advance, Whorfin, Essex, Archon); 193.9 m (Indomitable);
Height	; 46.0 m (Horizon, Advance, Whorfin, Essex, Archon); 53.2 m (Indomitable);
Mass	; 562,000 mt (Horizon, typical); 566,800 mt (Advance); 569,200 mt (Whorfin); 771,000 mt (Indomitable); 563,750 mt (Horizon Flt II); 567,750 mt (Advance Flt II); 578,500 mt (Essex); 574,500 mt (Archon, typical);
Performance
Cruise Speed	; w 3 (Horizon, Advance, Whorfin, Essex, Archon); w 4 (Indomitable);
Max Speed	; w 5.3 (Horizon); w 5.5 (Advance, Whorfin, Essex, Archon); w 5.1 (Indomitable);
Endurance	; 4 years (Horizon); 6 years (Archon); 3 years (Essex); 2 years (Indomitable, Advance, Whorfin);
Complement
Officers	; 35 (Horizon, Archon, typical); 32 (Advance, Whorfin, Essex);
Enlisted	; 278 (Horizon, typical); 268 (Advance, Whorfin); 289 (Essex); 294 (Archon, typical); ; ;
Tactical Systems
Beam Weapons	; Horizon: 2x laser emitters (1.2 GW) (twin bank) (fwd dorsal primary hull); 2x laser emitters (1.2 GW) (twin bank) (fwd ventral primary hull); 4x Type I phased particle cannon (900 GW) (single banks) (dorsal primary hull); 4x Type I phased particle cannon (900 GW) (single banks) (ventral primary hull); 2x Type H phased particle cannon (700 GW) (twin bank) (aft secondary hull); Advance: 2x laser emitters (1.2 GW) (twin bank) (fwd dorsal primary hull); 2x laser emitters (1.2 GW) (twin bank) (fwd ventral primary hull); 2x Type I phased particle cannon (900 GW) (single banks) (dorsal primary hull); 2x Type I phased particle cannon (900 GW) (single banks) (ventral primary hull); 2x Type I phased particle cannon (900 GW) (twin bank) (aft secondary hull); Whorfin: 2x laser emitters (1.2 GW) (twin bank) (fwd dorsal primary hull); 2x laser emitters (1.2 GW) (twin bank) (fwd ventral primary hull); 2x laser emitters (750 MW) (below secondary hull stern); 2x Type I phased particle cannon (900 GW) (single banks) (dorsal primary hull); 2x Type I phased particle cannon (900 GW) (single banks) (ventral primary hull); Indomitable: 3x laser emitters (1.2 GW) (triple bank) (fwd dorsal primary hull); 3x laser emitters (1.2 GW) (triple bank) (fwd ventral primary hull); 2x Type J phased particle cannon (900 GW) (single banks) (dorsal primary hull); 2x Type J phased particle cannon (900 GW) (single banks) (ventral primary hull); 2x Type J phased particle cannon (900 GW) (twin bank) (aft secondary hull); Horizon/Advance refit 2218/Essex/Archon: 2x laser emitters (1.0 GW) (twin bank) (dorsal hull centerline); 2x laser emitters (1.0 GW) (twin bank) (ventral hull centerline); 1x laser emitter (950 MW) (below secondary hull stern/amidships); 2x Type J phased particle cannon (900 GW) (aft hull); 2x Type J phased particle cannon (900 GW) (dorsal hull rim); 2x Type J phased particle cannon (900 GW) (ventral hull rim);
Missile Weapons	; Horizon: 2x fwd torpedo tubes (w/ 80 photonic torpedoes) (ventral primary hull); Advance: 2x fwd torpedo tubes (w/ 120 photonic torpedoes) (dorsal primary hull); 2x fwd torpedo tubes (w/ 120 photonic torpedoes) (ventral primary hull); Whorfin: 2x fwd torpedo tubes (w/ 120 photonic torpedoes) (dorsal primary hull); 2x fwd torpedo tubes (w/ 120 photonic torpedoes) (ventral primary hull); Indomitable: 4x fwd torpedo tubes (w/ 80 photonic torpedoes) (dorsal primary hull); Horizon/Advance refit 2218/Essex/Archon: 2x fwd torpedo tubes (w/ 55 photon torpedoes and 20 probes) (dorsal primary hull); 2x fwd torpedo tubes (w/ 55 photon torpedoes) (central primary hull);
Shields	; 1-layer conformal forcefield; Navigational deflector on primary hull bow; 2x auxiliary deflectors on secondary hull bow;
Laboratories	; Horizon, Archon: 1x GP; 1x astrophysics; 2x planetary sciences; 1x chemistry/life sciences; 1x linguistics; Advance, Whorfin: 2x GP; Indomitable: none;
Transporters	; 2x GP (3-pad); Mk I; 3x emergency evacuation (22-pad); Mk I; 1x cargo; Mk I; Select Advance, Whorfin upgraded to Mk II;
Auxiliary Craft	; 2200s, typical: 4x heavy shuttles; 10x light shuttles; 6x shuttlepods; Advance, Whorfin, Essex: 5x light shuttles; 6x sublight tactical craft; 2240s, typical: 5x light shuttles; 4x shuttlepods; 1-2x special environment craft (or 1 scout cutter);
Historical
Ships of Note	; USS Advance (NCC-1008); USS Archon (NCC-1370); USS Constellation (NCC-1017); USS Essex (NCC-1350); USS Guardian (NCC-1019); USS Horizon (NCC-1000); USS Indomitable (NX-1023); USS Meteor (NCC-1012); USS Republic (NCC-1371); USS Scotia (NCC-1006); USS Sentry (NCC-1010); USS Southern Cross (NCC-1376); USS Victoria (NCC-1013); USS Warrior (Advance); USS Whorfin (NCC-1024);
Canonicity
Design	SFC battle cruiser, ST: Legacy computer game Yorktown
Name	FSRC, SFC
History	FSRC, HCE, Timo
Delta Dynamics	SRM #296

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Latest revision as of 19:12, 14 July 2023

Background

Hobbyist's Guide

Although the heavy star cruiser was recognized as the mainstay of Star Fleet’s strategy of exploration and the de facto capital starship of the defense force early on, keeping the Fleet continuously supplied with even two dozen heavy cruisers of modern type seemed beyond the scope of the organization. In theory, resources would be very efficiently used in building these large, long range ships capable of independent action in all conceivable situations. In practice, allocating the required funds would beggar the rest of the Fleet, which still needed its destroyers, tenders and transports. Star Fleet had to strike an undesirable balance between quality and quantity, stressing the former to an unhealthy degree, and to keep hoping that circumstances would eventually allow for improving the latter as well.

In the 2180s, as the careers of the wartime capital ship classes began their inevitable downturn, it was again time to develop a heavy cruiser of superior attributes. Despite the problems with the dilithium-regulated powerplants, the basic designs of the preceding cruiser generation had proven completely satisfactory for both exploration and defense purposes. Yet there was a pressing need for more internal volume, which Star Fleet felt could no longer be provided by increasing primary hull size.

A new approach called for new blood. Invited to participate was the newcomer Chiokis Corporation of Andor, a junior partner at this point. Wartime shipbuilders still did a lion’s share of the work regarding both design and construction. When the first Horizon class heavy cruiser, NCC-1000, emerged from the dockyards in 2193, family resemblance to preceding capital ship classes was thus clear. Even to a casual observer, the two-hulled monster gliding out of the dock was obviously the old Yorktown battle cruiser – whether ‘slightly reworked’, or ‘finally done right’, opinions varied.

Standing in for the original primary hull was a leaner and meaner Geering saucer 117.1 m across and 8 meters thick on the rim, with a dorsal bridge superstructure offset to bow, and with a ventral torpedo tube bulge. Courtesy of Chiokis, the secondary hull was significantly enlarged in depth and width but at the same time streamlined with sleek, curving shapes and a stern undercut. The two short and broad pylons on the connecting section now sloped down for an improved positioning of the warp engine nacelles.

Internal arrangement took full advantage of the double hull configuration. Ten decks within the command hull held improved accommodation, uprated laser and particle cannon weaponry, high-tech laboratories, two computer cores, and a powerful navigational deflector backed up by steerable twin auxiliary units on the engineering hull. Protected conduits distributed power from the engineering section to these systems. The main phase cannon had two single retractable mounts aft of the bridge and two more aft of the ventral bulge; the main 120/1.2 laser mounts were paired ahead of the upper and lower protrusions. A twin-tube torpedo launcher with magazines for 80 shots could sustain a high rate of fire from the classic location at the bottom of the saucer. Two shield generators were also nested inside the saucer; the Horizon was the first major Star Fleet vessel to be entirely protected by subspace/graviton fields and omitting armor altogether. The generators were of Andorian Raakuv LHH manufacture in the first three vessels to be built, but Hycor systems of Earth origin were introduced for all later units.

The secondary hull was organized much like the Yorktown one, save for the difference in scale; shuttle hangars, workshops, fuel tanks and reactor systems were in their familiar locations. The shuttlebay introduced precision tractor beams for approach control, yet the devices proved so unreliable at this point that their use was discontinued for flight safety reasons. The uncluttered landing deck, free of mechanical docking and securing aids, nevertheless represented a quantum leap in auxiliary craft operations. The extensive hangars and workshops allowed up to fourteen craft of various types to be operated from onboard the cruiser.

In addition to the thoroughbred Sternn augmented fusion main reactor of 10:1 m/am ratio and peristaltic feed, two slightly more mundane auxiliary powerplants were housed in the secondary hull. Total power production was increased almost twofold over the Achilles, 30% over the Yorktown. Fuel reserves provided an endurance of four years, and a theoretical maximum operational radius of some 400 lightyears. In practice, far longer missions could be mounted even in primitive fuel replenishment conditions, as the reactors were provided with filtering systems that could accept virtually anything from seawater vapor to gas giant upper atmosphere wisps.

The Scarbak GPM impulse engines cowled onto the lower secondary hull produced almost three times as much thrust as the contemporary Caracal impulse units, and avoided all the complications and compromises of the two-stage Enterprise arrangement. The gigantic (200,000 tons, 163 meters) yet sleek and smoothly cowled PB-18 nacelles represented another drastic increase in propulsive power. New flux guide systems enabled vertical off-axis control of the field, and facilitated the change in nacelle positioning. Large tubular intercoolers were mounted in pairs atop nacelle aft ends, powerful deflectors in turn at the center of the forward domes. Hemispherical plasma exhaust diffusers astern could be retracted for rapid purging. In a 2199 test run performed by USS Scotia (NCC-1006), maximum power enabled warp 5.9 for two minutes, although a more reasonable warp 5.3 was set as the official limit. The fact remained that the Scotia had grazed warp six, and would indeed have exceeded it with just a 5% increase in power output, rather than the at least 45% suggested by contemporary engineering experience. However, the state of the art at the time did not allow for such power levels, so the slight but sudden drop in power requirements near warp 6 was not observed.

The initial design was fielded in large numbers for a capital ship of this size, 12 more cruisers being completed after the prototype in 2196-99 and even more being planned. Independent exploratory deployments outside known space were typical assignments, even though the capable vessels were also called to perform various military duties. The Horizon herself had a distinguished career of exploration under the command of Captains Mann, Gatulla and Broderick. The three-year expedition under Captain Mann established first contact with no less than 12 civilizations, a feat no longer believed to be possible after the early days of Enterprise exploits on a virgin quadrant.

Yet this mode of heavy cruiser deployment brought up critique as well. The defensive commitments of Star Fleet were as much compromised by block obsolescence as the exploratory ones, and the feline Xindi unrest of 2196-97 made ‘Where Is Star Fleet?’ a burning question in mass media headlines. The Commission for Star Fleet had no choice but to reconsider its procurement policy, and several Horizon contracts were pre-empted in favor of a type optimized for hearth world security duty. On the positive side, the Council released significant funds for increasing the total number of cruiser hulls from eighteen to twenty-six, now evenly divided between exploratory and defensive types.

The Advance subclass (with a scatter-shot range of registries from NCC-1008 on the inaugural ship to NCC-1022 on the final vessel) made use of the Horizon design and even of some partially completed spaceframes, yet carried a completely rethought tactical suite featuring new targeting systems, a heavier particle cannon fit and additional dorsal torpedo launchers. Most of the laboratory facilities were displaced by the new weaponry, and the shuttle hangar was rearranged to accommodate a small flight of tactical craft. The battle cruiser designation could now openly be applied on this subclass, built in delightful quantity yet at a relatively leisurely pace as military threats once again receded. The type turned out to be something of a disappointment when finally pressed to battle; the loss of USS Sentry (NCC-1010) to newly belligerent Klingons in 2209 put construction on hold before numerous tactical shortcomings (mainly concerning secondary hull armament, protection and power routing) could be remedied for the final three vessels.

At the resumption of the Advance run, the flawed original hull NCC-1023 was left uncompleted, yet in practice lacking little else besides warp propulsion and tactical systems. She was the ideal subject for an experimental upgunning when the Klingon offensive began: not pulled off the front lines at a critical moment, nor hogging any of the capacity used in construction of modern combatants, yet offering promise of reinvigorating a design that existed in decisive numbers. Key to the Chiokis/Armscor/CWD upgrade was PB-19, a 180 m monster engine capable of pushing a Horizon to supercruise. Changes to exterior included longer, stronger pylons that held the nacelles far apart, beyond saucer width; three nozzles per pylon for the impulse system; and significant expansion of the secondary hull, to 140 m total length. The latter was an absolute prerequisite for the major internal change, the installation of two Mann-class SSWR-IX reactors in parallel. Power aplenty could now be used to fire up enhanced shields and an increased number of main lasers. Some secondary weapons were replaced by phase cannon, and two more torpedo tubes added.

The weapon upgrade was an unqualified success, at least in test firings. However, the Indomitable (as NX-1023) did not get the chance to try the deadly arsenal on Klingon vessels. Trials of the drive system gave disappointing results, not so much because of design flaws but because of the disturbing unreliability of the overcharged power system. Star Fleet dared not send the ship to the battlefield, even had the embarrassed powerplant provider relinquished her. Nevertheless, the steps forward in weapons integration proved useful in virtually all the following military ship construction and upgrade programs – including that of the Horizons.

In 2218-19, a thorough weapon system upgrade was performed on all members of the Horizon and Advance classes. The entire torpedo loader assemblies of the surviving ships were removed and replaced with ones compatible with modern forced-intermix warheads, for which the Horizons were priority recipients. Also, laser fire control was upgraded to Indomitable standard, and the particle cannon were given better surge suppressors for 20% overcharging.

New units were added to Fleet strength as well, the lead ships USS Essex (NCC-1350) and USS Archon (NCC-1370) of the respective battle cruiser and heavy cruiser batches becoming further salutes to acclaimed Daedalus ships in 2222. These newbuilds incorporated the PB-22 engine, a rather minimally improved direct successor of the now dated PB-18. Yet thanks to adopting a version of the Indomitable secondary hull, with its vast volumes for fuel and supplies, they enjoyed an endurance and range advantage over the converted older cruisers, and represented a higher standard of accommodation as well. They are thus often considered subclasses distinct from the upgraded Advances and Horizons, respectively. For a few glorious years before the full operational introduction of the Baton Rouge class, they actually formed the defensive strongback of Star Fleet. Yet when the more modern alternatives became available, production of both Essex and Archon types was cut short at seven vessels.

None of the armament changes would have transformed the venerable heavy cruisers into invincible fighting machines anyway, as power systems still were unable to feed terawatt lasers or rapid-fire particle cannon. Nor did the acceleration, agility, speed or range of even the latest Horizon variants quite meet modern military standards or ambitions. While the significant research capabilities of the Horizons did give them an edge against Klingon cruisers by providing high-quality intelligence and analysis of enemy tactics and capabilities, a further boost in power and propulsive performance was decidedly needed.

Even though the class was nowhere near the end of useful service life, Star Fleet thus began considering a significantly more extensive upgrade option, mainly as an economical alternative to all-new dilithium supercruisers. In this prolonged process, modern hardware was mated to Horizon secondary hulls, as USS Constellation and USS Republic went through a series of experimental refits to find the ideal way of replacing the command hull with a larger and stronger concave-type saucer, and the old PB-18 or PB-22 nacelles with significantly more capable PB-3X series solid-state units. These refits are discussed in the Constitution entry in more detail.

On this foundation were laid the plans for innumerable later generations of ships. The basic design philosophy of the Horizon class has endured for almost 200 years now, both within Star Fleet and among many foreign space forces. It is only fitting that no examples of the class survive in museums or surplus depots – the continuing influence of the Horizons on today’s starship designers is heritage enough for the venerable design.

Delta Dynamics

Horizon class heavy cruiser

In the 2180s, capital ships from the Romulan War—comprised of myriad designs from the founding states—entered periods of inspection and surveys, with expected results: they were tried, tired, and increasingly out-of-date. Star Fleet responded with a call for a new heavy cruiser design. While "quantity" was a constant demand for the expanding service, the requirement for destroyers, tenders, and transports meant that this new generation capital ship had to stress "quality" foremost.

Chiokis Corporation of Andor, a sub-contractor on previous designs, introduced as its first ever primary submission what was immediately declared to be an updated Yorktown battle cruiser. A monster of a ship (at 562,000 metric tons), it was comprised of two hulls and bracketed by nacelles of significance, the PB-18s. The ship's length was an impressive 294.1 meters, with a beam of 117.1 and a height of 46 meters. The primary saucer hull, the broadest part of the ship, had a thickness of 8 meters at the rim, allowing not only quarters and weapon emplacements in the impressive 10 decks, but also six high-tech laboratories. The secondary hull had a clear lineage with that of the Yorktown, though it was enlarged both in depth and length, providing a sense of streamlining with its curving shapes and the undercut stern. The two outrigged pylons slightly sloped downward in order to provide improved positioning for the nacelles. The PB-18s allowed the ship to cruise at warp 3 and attain a maximum velocity of 5.3. The massive Scarbak GPM impulse engines cowled onto the lower secondary hull avoided all the complications and compromises of the two-stage Enterprise/Columbia arrangement.

The ship itself was equipped to sustain its crew of 35 officers and 278 enlisted on four-year missions over 400 light-years, protecting them with 2 banks of dual laser emitters in the 1.2 gigawatt range, eight Type I phased particle cannons (900 gigawatts), and two Type H (700 gigawatts) covering the aft. Eighty photonic torpedoes were also carried in the primary hull, fired from the battery on the ventral side. The Horizon was Star Fleet's first capital ship to go out sans any armor, fully confident in the ship's reliance on two shield generators to wrap the crew with a blanket of subspace/graviton fields.

Thirteen cruisers of this initial design were fielded, with more planned. The ships were respected for their capacity for independent exploratory deployments outside known space, as well as their various military duties. The Horizon herself had a distinguished career of exploration under the command of Captains Mann, Gatulla, and Broderick. The three-year expedition under Captain Mann established first contact with no less than 12 civilizations, a feat no longer believed to be possible after the early days of the Enterprise exploits. However, shortcomings were identified, especially in regards to "hearth world defense," which would be addressed with the follow-on Advance subclass battle cruiser.

Advance subclass battle cruiser

The Horizon class heavy cruiser was immediately respected for the exploratory capacity provided to Star Fleet, but there was, no doubt, acknowledgment of some shortfalls that needed to be addressed as the ships ventured forth. The class had been designed in a holistic sense to be a cruiser; however, the design that sailed from the rails to the border addressed the exploratory nature of a cruiser over that of the defensive role. The defensive needs of the Federation had to be addressed (as highlighted by the feline Xindi unrest of 2196-97) and rather than design a brand new battle cruiser, it was decided to adapt the Horizon and build this subclass alongside. The Federation Council released additional funds to increase the total number of cruiser hulls to twenty-six, evenly divided between exploratory and defensive types.

The Advance battle cruiser maintained the dimensions of her matriarch, but internal changes were significant. The tactical suite was rethought, with upgraded targeting systems, aft phased particle cannons swapped out to match the strength of the forward suite, and four of the forward cannon replaced by two additional photonic torpedo launchers on the dorsal saucer rim. Very little of the scientific nature of the original was retained, as most laboratories were ripped out to make space for the heavier tactical package. The shuttlebay was also re-designed to accommodate a small flight of tactical craft.

While the addition of the Advance was appreciated for the strength it provided to the "hearth world defense," there was a notable amount of disappointment with its actual battle prowess. Though military threats receded a touch in the design's initial years, when USS Sentry (NCC-1010) engaged the newly belligerent Klingons in 2209, it struggled against the aggressors and lost. The final three hulls were put on hold until the shortfalls could be addressed. Therefore, the class was limited to only ten named Advances (the hull for NCC-1023 was deemed flawed well before completion, and would be commissioned in a different subclass in 2210).

Whorfin subclass battle cruiser

The Whorfin subclass battle cruiser was the result of the resumed construction of the Advance subclass, of which further production had ceased following the analysis of the loss of USS Sentry to Klingons in 2209. The external changes were limited; visual inspection of one (of only three) of the variants would often result in mistaken identification as an Advance or even a Horizon. Internally, however, the chance to improve upon the tactical effectiveness of the battle cruiser led to changes in the power routing (specifically the energy weapons), protection (shielding and electronic warfare systems), and sturdier internal structures. The aft-facing phased particle cannons were removed, with two laser emplacements added to the ventral side of the secondary hull.

While the original nine Advances would not see the same changes provided retroactively (they would receive technological overhauls in 2218), they were retained in their original "hearth world defense" role, with their three younger sisters joining them. The upgrades proved the meddling's expense in 2229, when the USS Whorfin herself survived a Kshatriyan ambush with only light casualties, continuing on in service to the Federation (as a deep space survey cruiser over three tours), until 2297.

Indomitable experimental battle cruiser

The USS Indomitable battle cruiser was the one-off experimental continuation of an Advance hull that was tremendously overdue because of flaws that had gone undetected until late in the hull construction process. When USS Sentry (NCC-1010) lost its battle to the three Klingon aggressors in 2209, construction on the remaining Advance hulls was halted, and only resumed when the Whorfin subclass plans were released. The hull on NCC-1023, however, was set aside for a special purpose: an experimental upgunning intended to specifically address the emergent Klingon threat. The Indomitable hull was a fleet-management godsend, after all: an existing design could be used to rapidly develop this new battle cruiser concept without hauling an active ship off the tip of the spear, when it would be needed the most. The hull's advanced stage of construction also meant that critical shipbuilding assets would not be tied up, right when Star Fleet was considering how to pivot.

The key to this upgraded heavy cruiser design was the enormous PB-19. The 180-meter long nacelle was envisioned to push the ship to supercruise speeds. The pylons to support the nacelles were made longer and stronger, and far outside the breadth of the primary saucer. The Scarbak impulse engines of the preceding sister ships were miniaturized, with all six staggered along the two pylons, while not providing redundancy so much as impulse-capable survivability. Often lost because of and behind the massive scope of the nacelles was the significantly-lengthened secondary hull; its 140-meter length was intentional, to allow for the installation of two Mann-class SSWR-IX reactors in parallel. The tremendous amount of power provided by the two reactors meant that not only would the nacelles see the required amounts necessary for supercruise, but that enhanced shielding and an increase in the number of main lasers would also be well-supported. All the critical spaces that typically reside in the engineering hull needed to be accounted for, and that required an extension.

The weapon upgrade was seen as an unqualified success: where most Star Fleet ships sported single or dual-bank energy weapon emplacements, the Indomitable was prepared to put six 1.2 GW lasers (in two triple-banks) on any vessel "crossing the t", managed by an advanced fire control system. Those same aggressors would also have to deal with four 900 GW phased particle cannons and four forward-embedded torpedo tubes; two additional Type J cannons covered the aft quarter.

Unfortunately, the ship could not pass its warp trials: the fluctuating output of the temperamental reactors threatened to overload the electroplasma conduits that fed the thirsty nacelles. As so much hope was being placed on the upgraded cruiser, its frequent emergency down-warping was a common end result of any one trial, as witnessed plenty of times by the tailing Texas-class USS Altay (NCC-911). Star Fleet could not risk fielding the class with such an unreliable power system.

While the ship itself would not proceed to commissioned status, much less to subclass production, the weapons integration proved useful in succeeding military ship construction and in upgrade programs, including that of the various Horizon subclasses. The elongated secondary hull would also be adopted and adapted by the follow-on Essex battle and Archon heavy cruiser subclasses.

Horizon Flight II heavy cruiser

In 2193, the USS Horizon sailed from the rails, ushering in an era of serious contemplation by Star Fleet on the role of the heavy cruiser in both defense and exploration. Twenty-five years later, Star Fleet firmly understood the continuing importance the Horizon class (and its subclasses) had as a core component of the fleet. While not advancing as quickly as it would later in the century nor as fast as the Federation would have preferred, technological progress continued forward and the fleet captains for these heavy cruisers were able to successfully advocate for enhancing the capabilities of their ships. Specifically, this refit would focus on the weaponry of the original Horizon class, as well as the Advances.

Priority Number One was upgrading the hard-hitting torpedo systems. In the Horizons, the launch assemblies located in the neck bay were ripped out and replaced with an auxiliary control room (the previous, smaller, one located centrally in the neck was turned into a medical quarantine space). Now, instead of two co-located tubes, four additional ones were embedded into the primary saucer: two comprising one wide bay on the central command island and two additional ones on the forward rim of the hull. The introduction of modern forced-intermix warheads allowed for these separated locations to make use of specialized antimatter storage, rather than utilize the AM conduit that fed directly into the matter/antimatter reaction assembly in the engineering spaces. To make some room for these rim-embedded launchers, four phased particle cannons were removed; the remaining six were given better surge suppressors, for 20% overcharging (Type J). An additional 950 MW laser emitter was placed on the ventral side of the secondary hull, right below the hanger bay; the entire laser fire control was upgraded to the Indomitable standard.

To help the fleet managers differentiate the capabilities of the modified ships over those awaiting the refit, they were designated as Flight II Horizons.

Advance Flight II battle cruiser

In 2218, the Advance subclass battlecruiser, along with the primary Horizon class, entered drydocks for an upgrade period focused specifically on enhancing the tactical suite. For the Advances, that meant replacing the torpedo bay located in the "neck" of the ship with an auxiliary control room (the previous, smaller one located centrally in the neck was turned into a trauma ward). Space was cleared out of the command island for a newer torpedo bay designed around modern forced-intermix warheads, and the two individual bays already present on the saucer rim were also upgraded. The phased particle cannons were replaced by newer models (Type J) that made use of better surge suppressors for 20% overcharging. An additional 950 MW laser emitter was placed on the ventral side of the secondary hull, forward of the GNDN interface; the entire laser fire control was upgraded to the Indomitable standard. Interestingly enough, the main battery of lasers (forward saucer, dorsal, and ventral) were downgraded from 1.2 GW to 1.0 GW, for better heat management (which had been impacting the life span of the emitter coils and lenses).

To help the fleet managers differentiate the capabilities of the modified ships over those awaiting the refit, they were designated as Flight II Advances. This would be the last major upgrade before this subclass was fully decommissioned in 2258 (11 years after the last Horizon Flt II was retired).

Essex battle cruiser

Four years after the first of the veteran Horizon subclass heavy cruisers and Advance subclass battle cruisers received their Flight II upratings, newbuilds of even greater advancement were commissioned into frontline service with Star Fleet. The battle cruiser variant continued the homage to the hero vessels of the Daedalus class of the preceding generation with the USS Essex (NCC-1350), the first in this latest subclass. With the same weapons loadout of the Advance Flt IIs, as well as the same overall dimensions, a position paper about the ship would not appear to do it justice: the ship had a secondary hull design borrowed and modified from the failed Indomitable experiment, providing it an immense internal volume unavailable to its predecessors. This increased the ship's range and endurance, due to the enormous increase in fuel and supplies carried (when compared to the older, converted cruisers). The higher standard of accommodation was also appreciated by her crew. The PB-22 warp nacelle was a slight improvement on the PB-18, decreasing individual unit mass for the same performance characteristics, through more advanced (but smaller) primary buffer panels and an intercooler that maximized efficiency with increased length (but less of a physical footprint).

While the Baton Rouge class was also first commissioned in the same year (2222), the operational history of the Advance subclass allowed for instant familiarity for the Essex and her sisters, meaning the ships were at the forefront of Star Fleet's strategic defense policy for a few of their early years. However, as the more modern heavy cruisers increased their numbers and operational responsibilities, the production of the subclass was quickly slashed to seven (from the envisioned twenty). In the end, these newest of the Horizon series still failed to provide the expectations of acceleration, agility, speed, or range to meet modern military standards or ambitions. Hence, Star Fleet would consider how additional upgrades could provide boosts in power and propulsive performance, in a direct impact to what would eventually result in the Constitution class heavy cruiser of the 2240s. The last Essex would be decommissioned in 2251.

Archon heavy cruiser

Four years after the first of the veteran Horizon subclass heavy cruisers and Advance subclass battle cruisers received their Flight II upratings, newbuilds of even greater advancement were commissioned into frontline service with Star Fleet. The heavy cruiser variant, like the concurrent battle cruiser variant, continued the homage to the hero vessels of the Daedalus class of the preceding generation with the USS Archon (NCC-1370), the first in the final Horizon subclasses. With the same weapons loadout of the Horizon Flt IIs, as well as the same overall dimensions, a position paper about the ship would not appear to do it justice: the ship had a secondary hull design borrowed and modified from the failed Indomitable experiment, providing it an immense internal volume unavailable to its predecessors. This increased the ship's range and endurance (6 years, specifically), due to the enormous increase in fuel and supplies carried (when compared to the older, converted cruisers). The higher standard of accommodation was also appreciated by her crew. The PB-22 warp nacelle was a slight improvement on the PB-18, decreasing individual unit mass for the same performance characteristics, through more advanced (but smaller) primary buffer panels and an intercooler that maximized efficiency with increased length (but less of a physical footprint).

While the Baton Rouge class was also first commissioned in the same year (2222), the operational history of the Horizon subclasses allowed for instant familiarity for the Archon and her sisters, meaning the ships were at the forefront of Star Fleet's strategic forward defense policy for a few of their early years. However, as the more modern heavy cruisers increased their numbers and operational responsibilities, the production of the subclass was quickly slashed to seven (from the envisioned twenty). In the end, these newest of the Horizon series still failed to provide the expectations of acceleration, agility, speed, or range to meet modern military standards or ambitions. Hence, Star Fleet would consider how additional upgrades could provide boosts in power and propulsive performance, in a direct impact to what would eventually result in the Constitution class heavy cruiser of the 2240s. The last Archon would be decommissioned in 2263.

Gallery

Master Sheets

Horizon
Advance
Whorfin
USS Indomitable
Horizon Flt II
Advance Flt II
Essex
Archon

Other Images

USS Indomitable above
USS Scotia

Supporting Documents

Notes

Numerous surplus secondary hulls were constructed, as noted in Guide: Constitution and Guide: Achernar.

Jumped the completion of USS Horizon to 2193, to match the operational dates. The initial construction year was also changed to 2190.

Construction of contracts 1023-1025 were halted with the loss of USS Sentry in 2204. NCC-1023 would be re-tasked in 2210 as the NX-1023 USS Indomitable following damage during initial production, while construction on NCC-1024 & -1025 would re-start as the first two Whorfin classes. A third Whorfin (NCC-1029) would be finally ordered in 2212.

The original Spaceflight Chronology image for the Horizon has been replaced with the current style of images.

The construction of Guardian and Warrior is detailed in Guide: Byrd.

Text suggests only one dorsal torpedo launcher was added for the Advance, suggesting a single one only or the addition of one to match an existing one. However, the sidebar suggests the Horizon only had ventral tubes and that the Advance had 2 dorsal ones (n addition to the ventral), so the text has been amended.

The PB-21 nacelle was re-designated as PB-22, because of the very different design with the same designation in use with the Burke class.

Timo says the final Advance subclass had a registry of NCC-1029, but I've changed that to NCC-1022 (USS Warrior).

After some careful thought and a good deal of reluctance, I've raised the Advance production run to 10 (from 9), in order to fill in some empty NCCs left unexplained.

I arbitrarily determined the Essex class had an endurance of 3 years, primarily due to its enlarged secondary hull.

USS Essex comes very close to sharing the same commissioned period as the USS Essex of the Indianola subclass. Recommend the Indianola one not get converted/re-commissioned until after 2251.

Following decommissioning, the secondary hull of USS Southern Cross (NCC-1376) was used for USS Sirius (NCC-Txxx), one of the export heavy cruisers of the Achernar class.^[1]

References

↑ Guide: Achernar

[Achernar-1] Guide: Achernar

[1]