Technical Journal: FTL Travel

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by Andrew Modro

Travel between star systems at speeds greater than light is a staple of science fiction. Without the ability to transcend the speed of light, travel between even the closest stars takes years. In a place like the Frontier, FTL (Faster-Than-Light travel) is absolutely essential.

The STAR FRONTIERS game treats FTL in a very abstract manner, especially in the Alpha Dawn rules. Knight Hawks attempts to add a bit of flavor, but also confuses the issue when compared to Alpha Dawn. The purpose of this article is to examine interstellar travel and to provide flavor options for Alpha Dawn and Knight Hawks games that can be used without altering the rules as presented.


The Vast Deep

Space is big -- ask any Douglas Adams fan how big it is for an entertaining answer. Light, the fastest thing in the cosmos, takes years to traverse the cold dark between the stars. Galaxies are tens or hundreds of thousands of light-years across, and lie millions of light-years apart. The observable universe itself is many billions of light years wide.

Science tells us that nothing can travel faster than light. To travel from one star system to another would take many years. Even with incredibly powerful futuristic rockets, a slower-than-light ship would spend years accelerating ever closer but never completely up to the speed of light, then more years turning over and decelerating after the halfway mark. The "Inhibitor Universe" novels of Alastair Reynolds and Vernor Vinge's "A Deepness in the Sky" present excellent views of space opera in which light speed is never broken, and the consequences of that limitation.

But many are willing to believe that a way can be found to circumvent this cosmic "speed limit". Science fiction is full of faster-than-light travel of many wondrous varieties, from "warp speed" and "hyperspace" to "space folding", "wormholes" and "slipstream drive". Eventually we may discover a real-world method for getting around the limitation of light speed. In the meantime, we can dream.

The STAR FRONTIERS game touches on FTL only in brief. The Alpha Dawn rules only mention how fast FTL is, and do not describe how it is achieved. The Knight Hawks set does offer an explanation -- a unique method invoking the Void -- but does not sit easily with the Alpha Dawn explanation. This is more of an opportunity than a difficulty, however. Each GM is free to explain, in as much detail as she wishes, just how FTL is achieved in the Frontier.

FTL in Alpha Dawn

Alpha Dawn is quite specific about FTL. The rules state that travel between star systems takes one day for every light year of distance -- and that's all they say. What method are the starships using? Is it classic hyperspace? Space-time warping fields? Extra dimensional wormhole tunneling? Quantum foam sliding? We are not told. This leaves the door wide open for the GM's imagination and personal tastes. A few options are examined here.


The most classic FTL method in all of science fiction, hyperspace invokes a set of dimensions lying "parallel" to our physical universe. In this different space, distances between locations are warped or condensed, allowing a ship to traverse great distances in the real universe while moving much less in hyperspace, much like a grand cosmic "shortcut".

Hyperspace traditionally touches all points in our physical universe, but access can be limited by such things as gravity wells around large bodies like stars or giant planets, or by the necessity for powerful "jump gates" containing machinery much too large for starships to carry in their hulls.

Many variants of the hyperspace concept exist. For example, in some hyperspace concepts, ships can roam freely within the extra dimensional space, while in others they are restricted to prescribed routes due to navigational hazards (gravity wells, fluctuating distortion rates, strange alien inhabitants...) In some variants, "hyperspace" is a kind of infinite void in which nothing exists outside the ship.

Examples of science fiction using hyperspace are too numerous to encompass. The most famous is, of course, Star Wars, in which ships can cross an entire spiral galaxy in mere days.

Using hyperspace with Alpha Dawn is simple. The "one day per light-year" rule becomes an average cruising speed for ships in hyperspace. Some ships could be much faster, such as couriers and powerful small military warships. Some could be slower, such as heavy freighters or old junkers. Alpha Dawn games would likely use a version of hyperspace in which ships generally ply well established routes. Deviating from these explored courses could be possible, but would require great computational power and a lot of courage.

Space Folding

This concept turns hyperspace on its ear. Instead of traveling through an extra dimensional space just as it would through normal space, a ship using folding tech breeches space-time to connect two distant points, making a temporary bridge with no real distance at all!

This concept is related to the idea of wormholes. Wormholes are a kind of "space subway tunnel", slipping through dimensions outside our own normal space to bridge two different points. Space folding can be considered a kind of controlled wormhole generation.

Examples of science fiction using space folding are Frank Herbert's "Dune" novels, in which powerful psionics bend space-time to jump great heighliners across interstellar distances, as well as the classic Americanized Japanese animation series "Robotech". The first series of "Robotech" even shows us what can happen when space folding goes wrong.

Alpha Dawn can also make use of space folding quite easily. The time of one day per light year becomes applied to the incredibly complex computations required to plot the "fold jump". No mere organic mind could possibly hope to complete the computations for a single light-year jump in less than a lifetime.


A major twist on the hyperspace concept, a hypercatapult literally flings a ship through extra dimensional space on a carefully-plotted route. The ship cannot control its flight until it reaches the end of its journey and re-emerges into normal space.

The requirement for a stationary device to fling a ship across the light-years poses interesting restrictions beyond the normal hyperspace concept. What happens if a ship arrives at a point where there are no catapults to send it back? Can catapults be carried with ships and constructed on-site? Can catapults be "aimed" or are they linked in pairs? Can ships be "armed" with catapults that they can use to fling other ships away?

The use of catapults in Alpha Dawn games introduces an element of complex uncertainty that the core game does not normally include. GMs wishing to keep the game light and simple will probably not want to use this technology, but those looking for deeper flavor may wish to investigate all of the possibilities.

Jump Gates

Or JUMP POINTS or FIXED WORMHOLES: These variants are notable more for the idea of a fixed and controllable "entry point" than for the actual method of FTL. In each variant, ships must journey to a set location to make use of the FTL technology.

Jump gates, such as those seen in "Babylon 5", and jump points, such as in the "Starfire" military space opera novels, offer fixed points of entry into hyperspace. Entry into hyperspace may (B5's more powerful ships) or may not (ships in the Starfire universe) be possible outside of these fixed points. Jump gates are actual constructions which tear open a hole into hyperspace, while jump points are natural rifts in space.

Fixed wormholes, such as those in David Weber's "Honor Harrington" novels (which also use "normal" hyperspace), provide fixed points of entry into instantaneous- transit wormhole "tubes". They resemble jump points, except transit through them is usually instantaneous.

FTL in Knight Hawks

In contrast to Alpha Dawn, Knight Hawks presents a concrete and rather unique method of FTL. The basic concept revolves around the Void, an infinite gap of nothingness through which ships may move at incredible speeds. The difference in KH's FTL method lies in how the Void is accessed.

In KH, ships achieving one percent of light speed (0.01c, or 299,792.458 meters per second) cross over from the physical universe into the Void, where their effective speeds are multiplied because the distances between points are contracted. Slowing below this speed drops a ship back into normal space.

We are not told how this happens, however. KH tells us this is a "unique reality of space", and nothing more. While this is perfectly acceptable for a light, simple space opera, it won't take long before inquisitive characters -- and players -- begin poking their noses into the matter. As well, GMs can always use more options, and an examination of the situation provides many possibilities.

This section deals purely with Knight Hawks, the Void, and the "slip" that occurs at 1% of light speed, giving possible explanations for why the slip occurs and what can be done with it.

Editor’s note: It always bothered me that in Alpha Dawn rules, any ship traveling at .01C was instantly transported to void-space. What about photons? They travel much faster, yet remain in this reality. This article is an excellent discussion on the topic, and I’m curious how YOU handle FTL in your campaigns. Send me an email and I’ll post your methods in the Questions & Answers article in an upcoming issue.

Strange Physics

This basic method utilizes the assumptions presented by KH and does not go beyond them. The "slip" is an unknown, almost totally unknowable event that will continue to baffle physicists forever. Ships reaching 1% of light speed slip into the Void, and that's that.

While this method offers little in the way of even technobabble, it is undoubtedly the easiest of all possible methods, and is still perfectly valid depending on the tone of your game.

Void Engines

This method comes close to altering the game, but also provides a ready explanation for the effect as well as the ubiquitous overhaul requirement for ships traveling between star systems. Rather than a physical property of the universe, this method implies the use of a special, expensive and cantankerous piece of technology called a Void engine.

A Void engine bends and then breaks space-time, violating understood physics to shift a ship from "realspace" into the Void. It requires phenomenal power, meaning it can only be mounted on a starship of a certain size, and demands exquisite care in the form of overhauls. The strange realities of the Void require that a ship be traveling at least 1% of light speed before the Void engine can push the ship out of realspace and into the Void itself -- the exact reasoning can be left up to you as a GM, if you have a mind for technobabble.

Void engines are expensive beyond the ability of any normal PC to purchase. This enforces the STAR FRONTIERS trope of characters requiring passage from system to system instead of gallivanting about the Frontier on their own.

Void Rifts

Combining the "strange physics" explanation with the concept of "hyperspace lanes", this concept posits that certain lanes of space-time between stars are weak. Ships traveling along these lines can actually break through into the void if they push hard enough, but they are restricted to these paths. The physics of the Void still "kick out" any ship traveling less than 0.01c. Perhaps the Void is misnamed and isn't really empty at all.

GMs wishing to keep the simplicity of the basic KH explanation while adding a bit of modern believability can easily make use of this method.

Combining Alpha Dawn and Knight Hawks

The most common setup used in games that combine Alpha Dawn and Knight Hawks rules utilizes the KH explanation that almost all the time required for a voyage is spent accelerating and decelerating. This directly contradicts the AD explanation that voyage time is based on distance, however, because KH states that only a few seconds are spent in the Void and it would always take the same amount of time to accelerate to 1% of light speed for a given ship.

Reconciling these two contradictory setting elements requires some creative tap-dancing, but is not impossible.

Warped Time

The simplest reconciliation between the two is that while a Void jump takes only a few seconds for those aboard the ship, in normal space the jump takes the stated Alpha Dawn time of one day per light-year. This presents a great advantage in shipping time-sensitive things like wounded or perishable foodstuffs, but does nothing for those waiting in realspace for the ship to arrive.

Be Prepared

In this variant the nightmarishly difficult calculations for a Void jump take days, even for the most powerful computers. Every light year adds many hours to the necessary calculation time for a safe jump. These calculations are begun well before the ship begins its acceleration and are usually completed just as the ship reaches "slip" velocity.

Hop, Skip and Voidjump

In addition to the torturous hyper mathematics necessary to plot a Void jump route, it could be that a single Void jump isn't nearly long enough to take a ship from system to system. Each jump could cover as little as a light-year, and calculations for each jump would have to be made "on the fly". The ship would spend most of its time on the route in normal space, hanging between the stars and cruising, making calculations for its next hop through the Void.

Inspirational Materials

The author recommends the following for those interested in various presentations of FTL travel in science fiction:

  • Babylon 5 (Jump gate hyperspace)
  • Star Trek (Space-warping allowing FTL motion)
  • Star Wars (Classic hyperspace, including laborious calculations)
  • The "Honor Harrington" novels by David Weber (multilayer hyperspace and wormhole tech)
  • The "Starfire" military space opera novels by David Weber and Steve White (jump point-reliant hyperspace)
  • Robotech (my introduction to the "space fold" idea)
  • Angelmass, by Timothy Zahn (my introduction to the hyperspace catapult)
  • The "Inhibitor Universe" novels by Alastair Reynolds (no FTL; an attempt to achieve FTL goes horribly wrong; cryosleep and time dilation ahoy!)
  • A Deepness in the Sky, by Vernor Vinge (more non-FTL space opera)
  • A Fire Upon the Deep, also by Vernor Vinge (an odd universe where FTL is possible only if one travels far enough away from the galactic core; technically the same universe as Deepness)