Sensor/Stealth Test

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Sensor/Stealth interaction test

A sensor sweep is rolled at D10 + sensor power, rerolling and adding all 10s. Normally a sensor sweep rolls 1 dice at Long range, one additional at Medium and a third at Close. All targets with a stealth rating below the roll(s) must make a saving throw for each detection success made.


If the save is successful, the sweep has detected a 'contact' which can be further followed; if the save is failed there is sufficient accuracy on the sensor solution to enable weapons fire, though the target's Evasion may recieve a bonus. A ship may fire on a non-targeted contact by Blindfiring, however this is guaranteed to provide a substantial bonus to the target's evasion.

Sensors

Visual Detection

No matter how sophisticated a ship's sensors, there are some things for which a pair of eyes is best. At the very least, visual confirmation of an object can positively identify what it is and what its intentions appear to be. An enemy ship must roll twice in order to break out of targeting solution while within visual range. However, visual sensors are very poor at dealing with obscurants such as Starway weather, which are doubled in effect for Visual sensors.

Bridge Tower

A bridge tower doubles visual range of a ship but can be struck on a critical hit. It generally is an unacceptable compromise on ships designed for stealth but usually is quite useful for any ship.

Tech Sensors

TL1

+0 Mk.1 Eyeball
Sensor Power: +0
Sensor Ranges: 5/10/20
Passive, Visual

TL2

+1 Optical Rangefinder
Sensor Power: +0
Passive, Visual
An enemy ship within visual range will be automatically converted into a target if it ever becomes a contact.

+1 Searchlights
Sensor Power: +0
Sensor Ranges: 20/--/--
Visual Range: +10
Visual
Searchlights are the old fashioned method of picking up visual contacts.

death lights
blinders

+3 Etheric Discharge Detector
Sensor Power: +X
Sensor Ranges: 20/30/40
Passive
The Etheric Discharge Detector looks for energy reactions incidental to the operation of high technology and any form of magic. As such, the EDD increases in effectiveness the more high technology and magic is being used. The former tends to be easier to mask than the other. EDD's have great trouble finding ships running silent and may have issues prosecuting a sorcerous contact before spell signatures subside. Later versions provide more information with regards to the nature of the discharge.

+2 Acoustic Search
Sensor Power: +X
Sensor Ranges: 15/25/35
Sonar optimized for returns in deep sky. Works only inside starways and, ironically, nebulae.

+2 Magnetic Detector
Sensor Power: +X
Sensor Ranges: 15/25/35
Passive
Magnetic Detectors search for the magnetic fields of metal hulls. Its power against a ship is equal to its base MDP, but will not work unless it has Steel or Composite armor.

MRI

TL3

Radar
Infrared
Laser Rangefinder
Turbulence

+1 Basic Search Radar
Sensor Power: +X
Sensor Ranges: 10/20/40
Active

+3 High-Frequency Radar
Sensor Power: +X
Sensor Ranges: 15/25/35
Active

-1 Minehunting
Power +X
Range: -10/-10/-10

+4 Low-Frequency Radar
Sensor Power: +X
Sensor Ranges: 15/30/80
Active

+6 Over-The-Starway
Star Way Search +0.5 GL
Active

+3 Wake Detector
Wake detection time: 2 days
Passive

TL4

Full Spectral Sensor
Gravitometer
Particle Emissions

TL5

Quantum Flux
Psionic Detector


Permutations

High-frequency sensors; high sensor power but small medium/long ranges.
Low-frequency sensors; moderate sensor power with extended long ranges.
Towed sensor arrays; disabled if ship is forced to make an evasion roll.
Wake detectors; bonus for being in star ways.

More esoteric things

Over-The-Starway sensors; for detecting from star systems into star ways. Big, for use in forts and large warships?
Star Way cloud generators, for mobile concealment.


+0 Telescopes and Lookouts
Sensor Power: +0
Sensor Ranges: 5/10/20
Doubles all Star Way effects.

+0 Simple Magnetic Sensor Array
Sensor Power: +2
Sensor Ranges: 8/15/30

+0 Simple Search Radar
Sensor Power: +3
Sensor Ranges: 10/20/40

+0 Simple Gravitometer
Sensor Power: +4
Sensor Ranges: 12/25/50

+0 Simple Quantum Flux Detector
Sensor Power: +5
Sensor Ranges: 15/30/60


Stealth

All ships have a default stealth value, as well as a stealth coefficient which modifies the cost/space of stealth systems depending on the size of the fitted equipment. Many stealth systems also reduce the slots available for weapons/armor, on top of their cost in Option slots.

Stealth has two routes; Passive Stealth and Active Stealth. Passive stealth tends to have lower bonuses and inferior saves, however they are better at increasing effective range for enemy sensors. Active stealth has generally better bonuses and saves, but does not provide as much of a penalty to enemy sensor ranges. Also, some active stealth systems may interfere with the host vessel's own sensor systems.

Examples

+2X Simple Passive Stealth
Weapon/Armor reduction: X
Stealth +5
Stealth Save: 7+
Range Increase: +10 This adds to the actual range, making the stealthed ship act as if it were more distant
Evasion +1 Evasion bonus is doubled if the target is attacked with Blindfire.

+3X Simple Active Stealth
Weapon/Armor reduction: X
Stealth +8
Stealth Save: 6+
Range Increase: +5
Evasion +1

Etheric Countermeasures

Many ships are equipped with jamming equipment. A typical ECM jammer will have Range Decrease and will also decrease the Stealth rating of the jamming ship. However, ECM provides large benefits to other ships in the area and has lesser bonuses for itself as well by interfering with fire control. ECM systems are generally not affected by a ship's stealth coefficient.

Tactics

Running Silent

While as a matter of course warships at war minimize their emissions, stealth ships may go beyond this by eliminating all emissions as humanly and technologically possible and becoming 'holes in space'. This typically involves deactivation of shield systems, reducing speeds to limit scatter and relying solely on passive sensors. The upside of course is that this makes them even more difficult to detect, but a ship caught in this state is particularly vulnerable.
Running Silent allows stealth saves to be re-rolled, but halves speeds, deactivates any shield, ECM and other active systems and reduces all sensor rolls by 1 dice.

The Layer

The Layer is the colloquial term for the often shifting, stormy boundary between the relatively clear inner starway and the dense, stormy outer layer. As a general rule, it reflects and refracts energy, making detection across the Layer notoriously difficult.
Detecting targets on the other side of the Layer penalizes sensor rolls.

Pirate Sailing

While standard shipping routes and courses go through the middle of starways where the deep sky is clear and the sailing is fast, those with intent to stay hidden will sometimes travel through the stormy outer edges. Pirate Sailing halves speed but offers greater protection from being detected, as they are on the other side of The Layer from most shipping. Ships may only Pirate Sail along White or Blue lines.

Red Lines

Red Lines are routes with the paradoxical combination of thin ether and strong storms. This makes them difficult to sail in quickly, halving all strategic speeds and making detection difficult. Ships sailing along Red Lines are always in a state of Pirate Sailing.

Tracking targets

A contact that has not been successfully targeted but is tracked for consecutive rolls recieves a -1 cumulative penalty to its stealth saving rolls. A contact that successfully breaks contact removes all such penalties.

Biosignatures

The collapse of the Ether Storms and the subsequent migration of previously astrographically-limited space-living animals into known space has filled the skies with strange cries and sensor signatures. This has posed a problem for sensor operators, as canny opponents will often use flocks or individuals to mask their presence, concealing themselves as harmless sylphs or other deep sky dwellers.

Space Mines

While not strictly speaking derived from stealth technology, mine warfare is related, particularly in the use of extremely high-frequency (and thus high fidelity) sensors to detect mines. The small size of space mines (rarely significantly larger than a human in a bulky spacesuit) means that even relatively unsophisticated weapons can be difficult to detect.



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