The SpARC drive

(Pictured: a mid-class Mk.VIII 'whirlwind' Linear-type dual ring SpARC drive, a common choice on civilian freighters and cruise vessels.(Heckler-garret reactor cut-away for demonstration purposes))

"Most people take these big hunks of metal for granted. Gonna be honest, i do too a lotta the time. But without them, where would we be, really?...Probably using some sucky tachyon doohickey whatchamacallit engine invented by some alien shmucks.
Wouldn't nearly be as good as our old sparky's, things run like a dream and just give you a simple window from A to B, what a marvel.
-Harvey Kriste, renowned mechanic on the Jewelrind belt

Summary

Within the entire history of the empire, has no advancement ever been hailed as nearly as important as the SpARC drive. It is with most certainty, the main piece of equipment keeping the empire held together.
They are the primary method of FTL across every sector, used in countless thousands upon thousands of vessels due to their convenience, relatively low cost and general ease of operation. In every decently sized ship you're likely to find one of these drives, and they can range from small ones a mere few metres, to gargantuan multi-injector, multi-core constructs for use in all manners of uses and operative cases, including stationary permanent installations.
SpARC is an acronym, standing for Space-time Actuality Reconciliation Choke, named so due to its method of operation, which will be detailed somewhere below. Due th this operation though, these drives are perfectly capable of travelling vast distances of space to any distance depending on how much power you're able to pump into it, how large the drive is and how long you want to spend calculating in order to prevent a merge event.

Background

The SpARC drive was engineered almost accidentally a few thousand years ago as a result of the exodus project. During the journey of the city fleet toward their destination, a small population of scientists and engineers were kept awake to not only give Vulkan company, but also to develop new technologies in preparation for their arrival.
One of the investigations brought up were on Vulkan's own physiology and his relation to the universally mysterious dark matter. As it turns out, this lead down a path of discoveries in relation to the properties of space-time in relation to dark matter and to which conditions may allow for much easier reaction with fundamental forces and particles.
Of course, they weren't much closer to figuring how to achieve most of these specific conditions, and many of these pieces were missing, but what they did find was one application within practical reach, the amplification of space-time 'tangibility' via careful manipulation of hot particle fusion.
This would eventually lead toward the heralded invention of the first Heckler-Garret High frequency dark energy-fusion interaction proliferation Tokomak, a wonderful and highly complex piece of equipment which can be regarded as the main reason SpARC drives even function in the first place. This first reactor, created under a project led by two teams of scientists with their own heads, Terrison Heckler and Julian Garret, went through a large number of iterations and improvements before the theoretical drive was fitted around it and the first aperture, a mere 2nm wide was generated.
Now knowing the technology was safe and was perfectly capable of its function, it was quite quickly upscaled. Tests were performed on probes at first, then shuttles and animals, and eventually, a drive was constructed at a scale large enough to accommodate the transit of an entire cityship. Their preparation and resulting tests went astoundingly well, with the final large scale city transit transporting the entire spire 100km forward, thus absolutely proving its viability for long range faster than light travel.
A large chunk of material stockpiles were used, on top of a lot of recycling, in order to construct the SpARC drives for each of the largest city ships. Of course, a couple more years of tests and simulations were done before it was decided they were ready, and then in 2172, rough calculations were made, and the first large scale apertures were opened, cutting a journey of potentially thousands of years down into minutes.
Since then, it was immediately made more flexible and somewhat more efficient for use on smaller ships. Having FTL from the near beginning really bolstered early imperial colonisation across the Vulkania system, creating a massive ease in the realms of moving supplies and resources between planets and moons.
Like most imperial technology, it's been very carefully and consistently improved as time goes on, with countless variants, sizes and power brackets of drive for different ships, each having countless swappable components and modifications which can be applied depending on what the drive is needed for, and so in the modern day most ships come with recommended drive configurations to save buyers the hassle of inspecting every component, of course, full customisation is still an option.
Modern drives are additionally the most powerful and efficient that they've ever been, and so far it's hard to see a dead end to their development, and thus unlikely the drive will be replaced as imperial standard any time soon.

OPERATION

Imagine...getting a ball of solid rubber, and then shaking its molecules so fast it heats up and becomes soft. Then you scrunch that ball into a really small space and throw it at a wall made of the same rubber, causing the ball to expand and uh, dig a hole? sure...that's about the basics of how a SpARC drive works.
Yeah, I know.
-Prof. Kupffer Twinstar explaining the mechanics of SpARC drives in his book: 'Space-time through a camera lens' [Ch.2 pg.1]

Below is an extremely simplified diagram highlighting the basic vital components of a standard SpARC drive:

Purple: Power supply/Transformer array

Dark green: Cooling jet turbine

Yellow: Superconductive Mag-grav channelling ring arrays

Magenta: Heckler-Garret H-freq. dark energy-fusion proliferation Tokomak (HeG-MAK unit)

Orange: Inertial S-T hypercondenser

Light green: Pulse charge injection unit

Red: Primary reaction/expansion containment chamber

Pink: Hypercoil directional energy dispersal nozzle

[[!!warning: not-incredibly well thought science incoming!!]]
A SpARC reactor achieves FTL travel by projecting and stretching a small, dense pocket of space-time, sometimes mere millimeters in length, across a vast distance of many lightyears, often twisting over a singular focal point somewhere in space. The shape of this pocket is melded into a 'Hoeffel-hourglass' which results in a semi-self sustaining opening between its two ends, named Apertures.
The way it generates this specific field structure can be simplified into a number of important stages.
The first requirement to the process is of course, power, and plenty of it. A SpARC drive is often located very close to a ship's powerplant and usually hooked directly to its output transformers. This power is ran through the drive's own internal transformers to be distributed across all the equipment and components required for operation.
One such component is the air-jet turbine which is usually electrically powered and pushes a massive volume of air through the drive's structure to help keep the primary coolant loop at more stable temperatures. This turbine tends to be the loudest part of a drive when not active. Without the turbine, most drives will eventually overheat and cease function.

CONTENTS

Standard warning symbol designating SpARC operations

DESIGNATION:

Space-time Actuality Reconciliation Choke Long-range interstellar drive system

USAGE:

Immediate transportation of solid objects (ie.vessels) over cosmic distances via the use of hyper stretched space-time feedback tunnels.

FACTION:

The Royal Empire

BELONGS TO:

Royal Imperial institute of protected technologies

USE CLASS:

Any

INVENTED:

October 9th, 2132

INVENTED BY:

HProf. Terrison Heckler, HProf. Julian Garret

DISTRIBUTED BY:

Any government shipbuilding company

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SpARC teams

In order to not only maintain, but also upkeep the security of imperial technology, all viable ships are crewed with at least a singular drive team engineer. These specialised individuals can spend their entire careers learning the physics and inner workings of this technology and using that knowledge across any number of imperial vessels.
More prestigous engineers will be assigned to larger ships and more complex drives, but sometimes an engineer or a team may become too attached to their specific drive to work on another. They will often be quite quiet towards the rest of the crew, often mainly only interacting with other engineers and mechanics in charge of keeping drive systems integrated with the rest of the ship.
Additionally, as previously mentioned, these teams are in charge of drive security. They may call upon ship security, or be permitted to have their own equipment to deal with potential threats towards their drives and its pulse charges. It isn't very often that an issue like this might come up, but it has still come up many times, making it a necessary precaution. Exotic matter and nuclear material sells very well to the black market.

Military drives

Among the most powerful and sophisticated, military specialised drives can be extremely expensive and large. This is mainly because they are designed to be much more powerful than actually needed. This is to ensure that ships with damaged drives might still be able to evacuate a battle. It can also be for situations wherein other ships have inoperable drives and so a larger aperture can be used for multi-ship transit.
Military drives also 'burn' much hotter than other drives, a side effect of their field projection being far more rapid, causing a blue halo around the aperture instead of the classic orange. (see operations for a slight more detail)

Static drives

A peculiar phenomenon attained by having a sufficient inertial field generator positioned near an open aperture, and adjusting the shape of its field to correlate with the space-time structure of the window itself, Static drives are capable of keeping an aperture 'jacked open', feeding it with constant input energy while keeping a neutral balance of gravitational force in the space between it and the generator. This can allow the establishment of SpARC 'highways', permanent passages between systems which prevent the need for ships to use up exotic matter or pulse charges and making trade among the core worlds much much easier.
The major disadvantage to this drive is that the field generator needs to be huge, and even bigger for longer ranges. It eats up around the same power to sustain an aperture every minute than a drive of the same size does to generate one. This means facilities harbouring such a generator must have a massive dedicated power facility such as cold fusion or even low-end anti-matter powerplants to sustain it. A great example of this is the station of Dromidia orbiting Jade which sustains its cold fusion array using fuel taken directly from the gas giant it orbits.
SpARC highways are popular targets for pirates due to high volumes of cargo and civilian vessels, and so tend to be heavily guarded at either end. Additionally they can usually be switched off at a moment's notice by destabilising the inertial generator, preventing entry until re-established.

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