A
starship's engine determines how fast the ship moves. The more efficient the engine, the faster it can move the ship-and the more expensive it is. In addition, certain low-tech engines burn fuel of some sort, increasing the operational cost. In space, fuel-burning engines rely on vector jets to adjust their course, using fuel only in short, controlled burns to increase momentum.
To build a
starship engine from scratch, a character must succeed at a Craft (mechanical) check (DC 30) after investing 120 hours in its assembly. A character without a mechanical
tool kit takes a -4 penalty on the
skill check. The character must also make a
Wealth check against the engine's
purchase DC.
Installing an engine requires a successful Craft (mechanical) check (DC 30) after investing 60 hours in the process. A character without a mechanical
tool kit takes a -4 penalty on the
skill check.
The various types of engines are listed below.
Minimum Ship Size: The minimum size the
starship must be to have this type of engine.
Tactical Speed Bonus: The bonus that the engine provides to the
starship's tactical
speed, given in feet and squares.
Thrusters can propel a ship through a planetary atmosphere and land it safely on a planetary surface. Thrusters also serve as secondary engines when primary engines fail or shut down. Common types of thrusters include the scramjet, chemical rocket, repulsion thrust, or powered airfoil, although the exact form doesn't matter.
A ship with thrusters as its primary source of propulsion must refuel after every battle or every orbital mission. Thruster fuel has a
purchase DC of 31.
Tactical Speed Bonus: +0 feet.
This engine consists of a fusion reactor with one wall of the magnetic bottle missing, directing the thrust in the form of super-heated plasma. The fusion torch is intended for space-only applications; its exhaust stream would melt anything it landed on and incinerate everything within a few hundred yards of ground zero; it also expels a tremendous amount of radiation. Many ships fitted with fusion torch rockets use thrusters for atmospheric travel. Otherwise, they must remain permanently in space, relying on shuttlecraft to reach a planet's surface. The fusion torch uses hydrogen for fuel.
A ship using a fusion torch as its primary source of propulsion must refuel after every three battles or interplanetary trips. Fusion torch fuel has a
purchase DC of 23.
Minimum Ship Size: Gargantuan.
Tactical Speed Bonus: +500 feet (+1 square).
The ion engine generates power to break down molecules of a fuel material to create ions, and then expels them by means of a magnetic impeller. It doesn't provide as effective a mass-thrust ratio as the fusion torch, but it's more fuel efficient, and its exhaust is not nearly as dangerous. Ion engines don't function in any kind of atmosphere, so most ships with this kind of power plant also come equipped with thrusters.
A ship using an ion engine as its primary source of propulsion must refuel after every five battles or interplanetary trips. Ion engine fuel has a
purchase DC of 29.
Tactical Speed Bonus: +500 feet (+1 square).
Photon sails are immense but extremely fragile foil structures only a few molecules thick. Light pressure from a nearby star (or laser drive station, when available) provides motive force. The sails' acceleration rates drop to half if the ship is beyond the edge of a
star system and drop to one-quarter if the only available light is starlight. The sails can be wrecked by minor
damage, but every ship equipped with photon sails carries at least three spare sets. Unfortunately, it takes 12 hours to replace damaged sails, though deployment or stowage of the sails takes only 1 minute.
the deployed photon sails and prevents the ship from
moving until
the sails are replaced. The sail-ship continues on its last course and
retains its former
speed until the sails are replaced. Accordingly,
most sail-ships carry a secondary propulsion system (such as thrusters
or an ion engine) for emergency maneuvering and sailing against
the sun. Photon sails are completely useless in atmosphere-in fact,
they're instantly destroyed by atmospheric entry-making a secondary
propulsion system a virtual necessity for most sail-ships.
Minimum Ship Size: Gargantuan.
Tactical Speed Bonus: None.
Hands-down the best engine available at this or any previous
Progress Level, the induction engine uses artificial
gravity to provide incredible thrust and maneuverability. The induction engine requires no fuel and produces no exhaust; it's ideal for atmospheric, orbital, or deep-space work.
Tactical Speed Bonus: +1,000 feet (+2 squares).
PARTICLE IMPULSE ENGINE (PL 7)
The particle impulse engine is the next evolutionary step of the PL 6 ion engine. It uses magnetic fields to produce a constant stream of high-energy particles, as well as to provide vectored thrust. The major advancement of the particle impulse drive over the ion drive is that the particle impulse engine uses a negligible amount of fuel, which it also manufactures. The drive's reaction is so efficient that the tiny amounts of matter present in interplanetary or interstellar space can be collected through weak magnetic fields and converted into a thrust medium. Better still, the particle impulse engine is capable of atmospheric entry. It causes some
damage to any surface close to its exhaust ports, but nowhere near as much
damage as PL 6 engines do.
Minimum Ship Size: Gargantuan.
Tactical Speed Bonus: +1,000 feet (+2 squares).
GRAVITIC REDIRECTOR (PL 8)
A refinement of the induction engine, the gravitic redirector creates a gravitic singularity-essentially, a sub-microscopic black hole-in the vicinity of the ship, producing a constant pull on the ship. By changing the location of the singularity relative to the ship, the pilot can change the direction of the ship's travel. The gravitic redirector is more powerful and more efficient than the induction engine, and at the height of the technology's heyday, virtually foolproof. A gravitic redirector does not operate within a planetary atmosphere, and most ships fitted with this kind of engine also have secondary thrusters or rely on shuttlecraft.
Minimum Ship Size: Colossal.
Tactical Speed Bonus: +1,500 feet (+3 squares).
INERTIAL FLUX ENGINE (PL 8)
By precisely controlling the quantum energy level of every atom on the ship simultaneously, the inertial flux engine assumes the inertial states necessary to produce motion in any direction. In effect, by operating the controls, the pilot chooses from instant to instant what vector the ship's atoms will next possess, and the inertial flux engine alters them simultaneously-along with everything else aboard, including the crew and passengers. An inertial flux engine does not operate within a planetary atmosphere, and most ships fitted with this kind of engine also have secondary thrusters or rely on shuttlecraft.
Minimum Ship Size: Gargantuan.
Tactical Speed Bonus: +1,500 feet (+3 squares).
SPATIAL COMPRESSOR (PL 9)
The most advanced engine available, the spatial compressor surrounds the ship in a field that "folds" or "wrinkles" the fabric of space in the direction the pilot wishes to travel. This results in a continuous series of micro-jumps in which the ship flickers into and out of reality, teleporting thousands of times every second.
Since the ship has no intrinsic velocity (it's stationary while it teleports), the spatial compressor can instantaneously stop or change direction and thrust vector without any maneuvering whatsoever.
However, the engine still needs to build up cyclic
speed to increase the frequency of its microjumps, so it accelerates normally. The spatial compressor requires a lot of power, but no fuel. It is safe for atmospheric flight.
Minimum Ship Size: Colossal.
Tactical Speed Bonus: +2,000 feet (+4 squares).
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