- 1 Tropes
- 2 Insystem
- 3 Outsystem
- 4 Astrogation Schools
Brachistochrone transfer is almost always used.
The GM will provide an utzig stand-in system to determine trip length; if an utzig stand-in is unavailable, or for destinations not conforming to the standard “slot” positions, travel time will be computed using the chart/formula on S132. Once given the distance and trip length (AKA “the math”):
- Compare the trip distance in AU to the SSRT (B550) “Linear Measurement” column in yards, and note the “Speed/Range” penalty—longer trips are more difficult to plot accurately
- Example: A trip distance of 29 AU equates to 20 yards on the SSRT, which indicates a penalty of -6 in the “Speed/Range” column
- To plot the course, the navigator rolls Navigation (Space) modified by the above, and any equipment modifiers (assumes at least a Basic Bridge ship module or equivalent equipment/software), and modifiers for Time Spent (B346; base time to plot a course is 30 minutes)
- To execute the necessary maneuvers, the pilot rolls Piloting (High Performance Spacecraft); do not add the spacecraft's Handling modifier (these are not high-stress maneuvers)
- To find the final trip length, compare the worst MoS-4 of the two above rolls to the SSRT (B550) Size column, and add the Linear Measurement as a percentage to the trip length
- Example: If the rolled MoS is +3, subtract 4 for -1; compare to SSRT Size (-1) to Linear Measurement (3 yds); results in +3% to trip length.
If both Piloting and Navigation rolls are made by the same character on a capital-size vessel, both rolls are made at -4. Trip length may not be reduced to less than “the math.”
The location of optimal jump windows for a given destination depends on distortion caused by local gravities and stellar activity along the line of sight. Minimum distance for a jump window is 3 AU+(Stellar Radius(AU)x2). Actual distance to the window can shift radically over a relatively short time for many natural reasons (check per week, for changes). To find the actual distance (in AU), roll 1d6; 1=2d4+1, 2=2d6+1, 3=2d8+1, 4=2d10+1, 5=2d12+1, 6=2d20+1
For human-made anti-matter pion torch drives: at full standard acceleration, 10hrs of continuous use per cf of fuel per space of maneuver drives (or 14.58 days/space of fuel/space of maneuver drives).
FTL travel is a complex four-dimensional process, and despite the best efforts of modern theorists, is still more "art" than "science", requiring a great deal of intuition on the part of the astrogator (not unlike using "Kentucky windage" for a long-range rifle shot). The vessel's current location must be accurately fixed, the destination must be acquired visually using specialized sensors, and a complex galaxy model program is used to aid acquisition and to predict needed adjustments based on distance and movement. To date, scientists have not been able to devise a computer that can astrogate automatically.
The size of the drive's aperture and the available power determines the reach of the drive. The farther away the destination is, and the more the star's light is obstructed or distorted by gravity, magnetics, uncharted stellar objects, etc., the greater the margin of error on arrival (the slightest inaccuracy can set the vessel days, weeks or even months away from the destination within the destination system). Correspondence drives can be difficult to control, and frequently will inexplicably lock-on obstructions near the LOS (especially nebulae and, more often, dark nebulae, for some unknown reason). This is always inconvenient, and can be dangerous. As a result of the inherent danger of miscalculation, most spacers will only use proven, well-checked, guild-certified courses. Spacer legends abound about careless spacers using unproven courses and never being seen again. A reliable from-scratch course may only be computed if the Astrogator has complete up-to-date charts of the region. Often-used and user-modified courses are kept on the astrogator's blackbox, which experienced astrogators keep a closely guarded secret. Astrogation skill is M/VH, and only taught to an elite few. Some accomplished astrogators sell their work for a high price, making some of them quite wealthy and famous.
Natural jump gates, or wormholes, are spatial anomalies that act like a magnifying lens, allowing much longer jumps at safer margins of error. Oftentimes, a course will incorporate several wormholes in a chain, to further increase the effect. Wormholes are relatively common, although rarely useful, and new useful wormholes are an exciting find.
It is possible for a single vessel to create a Holtzmann wave large enough to encompass other vessels along with it, for towing purposes and such, but power requirements tend to make it more efficient for each vessel to have its own stardrive (except in the case of some small or fighter-craft). A tandem-jump is generally only attempted when the vehicle being towed either has no stardrive, or its stardrive is non-functional; otherwise, the operation is performed as a parallel jump. Gearing up for a tandem-jump requires a Chk:Engineer(Stardrive)-1(±size mod difference); Fail=stardrive burnout.
Any of these conditions can be made into a Technique.
- Existing Course: Assumes a guild-standard blackbox and guild training, and the vessel is at the recommended jump-off point. The attempt takes a base of 30min to lay-in the course. Each course description includes a difficulty modifier (how tricky it is to lock-in the system) and a "Malf" number (the presence of LOS obstructions). Chk:Astrogation ±[mods]; must designate a destination (planet, station, jump-off point, etc.) within the target system. Modifiers include +1 @>¼ Reach, -1 @½-¾ Reach, -3 @¾-full Reach, -5 @full-1¼ reach (max); if the vessel is not at the recommended jump-off point but is still in-system, -1 for 1hr, and a further -1 per doubling (-2 @2hr, -3 @4hr, etc.); standard Risk, Equipment and Time modifiers. Result(abstract)=final position in-system (relative distance (Pc)) x .001 AU from destination ±(result x10% (10% min)); cSucc=10%, regardless of actual result (other effects @GMD); cFail=see Astrogational Errors. If needed (@GMD), a single/double-clock check (1d12 (x2)) may be used to determine direction from destination. If the die roll equals or exceeds the "Malf" number, the vessel is diverted, regardless of skill. This is the basic skill, and cannot be improved as a Technique, although individual penalties may be reduced as individual Techniques, up to Default level.
- Parallel Jump: The Astrogation solution for a single ship may be passed on to other ships in a convoy. In such a case, the Astrogation check is made at a further -3, and all ships in the convoy must be close together (-3 to -5 depending on how spread out the convoy is). As a Technique, this cannot be improved above Default.
- Blind Jump: Blind jumps to a particular destination (when the destination is totally obscured) use pure intuition, and are at a base of -10, plus distance, Time and Equipment modifiers. Jumping blindly to "anywhere but here" is also at -10, but either the Astrogator or GM picks a random target (location/distance) and treats it as a "wrong system" result below. Blind jumps are at -2 Malf (for known courses) or a new (randomly determined) Malf. As a Technique, this may be improved no higher than Default-5.
- Diversion Recovery: If a vessel is diverted by a course-hazard, the course will have to be re-plotted, or a new course created. If the Astrogation check succeeded but was diverted anyway, the vessel is still basically on-course; treat as existing course at the current range. If the Astrogation check failed, the course must be created from scratch from the vessel's current position (at +2 for mFail).
- New Course: Assumes guild-training, complete charts of the area, a guild-standard black-box, and requires a base 100-(EffSkill x5)hrs. (Sct)Chk:Astrogation-10 ±[mods]; Result=course difficulty ±1 per ±3 result; cFail=cannot plot course; mods include -1 per 500Pc (or fraction), +2 for being on-site, and standard Equipment and Time modifiers. Starting Malf number is determined by GM (arbitrated or randomly determined (10+1d6)), and is improved separately. Once plotted, it is considered "untested" until it is actually used; the GM may say the Character has a good or bad feeling about the new course, but he won't really know until it's been tried. Once it has been used, the difficulty and Malf number is known, and it is considered "existing". Even a generally crappy course will still be usable, and it may be improved upon later. As a Technique, it may be improved up to Astrogation-5.
- Improve Course: Works generally like plotting a new course. Astrogator must choose to adjust either difficulty or Malf. When attempting to adjust difficulty, check as for plotting a new course; Succ=+1 improvement; xSucc=+2 improvement; cSucc=+2 improvement and +1 Malf; cFail=Astrogator cannot improve the course (or other result @GMD). Attempting to improve Malf by finding a better way around obstructions requires a check as for plotting a new course; Succ=+1 Malf; cSucc=+2 Malf; cFail=cannot improve the course.
Time-lost(abstract)/off-position on normal Fail, as described above; cFail=wrong system (GM arbitrates or determines new destination randomly using Grenade Scatter (distance in 100Pc); re-roll Astrogation check for system position, based on available destinations in target system), or must take evasive action to avoid hazard (danger-close to planet(oid) or comet, in the middle of asteroid field or meteor shower, in the gravity well of planet or black hole, etc.), the nature of which is determined by the GM (arbitrate, or determine randomly); if new position is not currently charted, a new course must be plotted. If the vessel is diverted, the GM may arbitrate or randomly determine the nature of the diversion. Once the immediate situation is dealt with, a new course must be set-in from the current location.
- Dust Clouds: The most common "unintended" destination, as they are sometimes difficult to see or predict. A vessel caught in any cloud may be blind (visibility anywhere from 10-1000km); some particularly nasty clouds are inhabited by asteroids, protostars or stellar debris that can damage or destroy a vessel. A vessel caught in a nebula will have to either wait for a "break in the clouds" or make a blind jump. Roll 1d6 per day (if the vessel remains still) or 4-hr period (if the vessel is moving); 1=pass through, 2=conditions ease (temporary break, thinning, debris clears), 3-4=no change, 5-6=conditions worsen (visibility reduced, debris increased). A vessel that is moving risks collision (avoidance is more or less difficult based on visibility and speed).
Execution of a jump requires three checks, as per GT119; Piloting and Engineer checks are treated as a standard (forced) Assist check for purposes of calculating the Astrogation result. There is a slight visual distortion around the ship at both the Window and destination simultaneously, as it winks out of existence and winks in at the destination. The signature is more pronounced when viewed on gravitic detection sensors, as a torus-type wave signature around the ship that expands at nearly the speed of light, continuing for many AU's before it dissipates. This gravitic signature is shaped differently for different types of stardrive, referred to as the drive's "fingerprint," and can be used to identify an incoming ship. The ship retains velocity and orientation through the jump (actual, not relative, as per GT119).
Microjumps are jumps within a given star system. Although covering much smaller distances than normal jumps, microjumps are not easier, due to mechanical constraints of stardrive technology, and depend as much on the (Stardrive) Engineer as the Astrogator. They still require a clear line of sight, which can be problematic near asteroids and such. Generally, the longer the stardrive's reach, the more difficult it is to perform microjumps. In addition to the normal Astrogation prep requirements, a microjump requires 30min of Engineering (Stardrive) work to re-tool the aperture. ETA result=normal ETA (figured as above) or remainder /(success result) or x(failure result). It is entirely possible for a microjump to take the ship farther from it's destination. Base difficulty for a microjump is -(ship's Reach/500 (round off)). Some smaller ships not meant to leave a system are built with stardrives that are only capable of microjumps, and their astrogators perform these jumps at +0, and do not require any Engineers' assistance. As a technique, this can be improved up to Default+3.
It is possible to tow another vehicle through a jump, by extending the threshold to encompass both ships. This requires a Chk:Engineering to successfully tune the stardrive for the jump; Fail=drive failure/burnout. As a result of power requirements, the effective Reach of the drive is reduced by the same percentage that volume is increased (by adding the two vehicles' displacements together).
It is possible to temporarily extend a ships reach slightly, at a higher power requirement and risk of burning out the drive; Chk:Engineering; Succ=result x2.5% (25% max).
Route descriptions should include a "Malfunction" number indicating its difficulty (e.g. 16 if course is completely unobstructed (rare), 14 if course goes through the core systems or 12 if course is obscured by nebulae or similar phenomena). If the die roll equals or exceeds the Malf number, the drive has locked onto the wrong target and the vessel will emerge in the wrong location (GM determines the exact nature, based on course description if available).
Guild members have a +1 bonus to all astrogation checks when in the Guild's (not the astrogators') home sector.
The Thaareh have a long-standing monopoly on all astrogational training within the CHW, though membership is generally open to all races. Members tend to learn at least some of the Qebish language during their training. Navigators are more familiar with hazards in the Human Sector; +1 Malf on all standard courses in the Human Sector. However, Navigators are cautious about unproven courses; -1 Plotting.
The Spacing Guild
Guildmen are more adept at avoiding astrogational hazards; Malf +1. However, their extensive calculations take extra time; +50% time for any Astrogation check.
The Brotherhood of Steersmen
Tohre-Chi astrogators are more seat-of-the-pants than the others, training Steersmen to use their intuition to maximum effect; +2 to Plotting and Blind Jumps. Their chaotic tendencies are passed on through their instruction; +500Pc to jump distance for purposes of calculating ETA for all jumps.
OKU pilots value long reach, and are more familiar in the Ozrahdi Sector and the Core Systems; ¾+ reach is at -2 (instead of -3). They are also more experienced with ultra-short range jumps; +1 to microjumps, only when using Ozrahdi equipment. However, they don't respond well to chaos; -2 Recovery.
Astrogators are sometimes illegally taught by (former) guild members, especially among pirate/smuggler crews or similar situations. In these cases, they are generally less precise and disciplined; +500Pc to jump distance for purposes of calculating ETA for all jumps. Without formal training, plotting new courses is dangerous; -4 Plotting.
Splinter groups of existing guilds, secret societies, or pirates might have their own specialties, @GMD.