Archive for the Intercept Category

November update

Posted in Intercept on October 31, 2018 by Anders Backman

Damage in Intercept is to simply take the weapons DAM value and subtract the targets DAB value. Use this number and add the highest of 2 D6 if a Very Good hit, 1 D6 if a Good hit and the lowest of 2 D6 if a Fair hit. Should be simple enough.

In order to simplify this a bit further I have precalculated DAM – DAB values for each predesigned ship in Intercept bundle and Designs. During play all you need is to determine your weapons DAM value and add the die roll to it as above, the damage result can simply be read from the damage table on each ship design.

Precalculated damage table

This damage table* tells us that we need to roll 23 or more to at least get a Scratch hit. A damage roll of 35 or more will destroy the ship if it was a Hull hit, otherwise it will destroy that location and by pass on damage cause Critical hit. A damage roll if 38+ will utterly destroy the ship wherever it hits.

Before checking what damage our damage roll caused we should check the box below the damage table. If the hit was a Partial penetration (meaning the PEN of the weapon was less than 4 above the ARM of the target) we go down one row. If the hitlocation was Surface or Thrust we go up one level. No effect is still no effect so no row shifts apply if the hit was No effect.

Free trader weaponry

Let’s take a look at the weaponry*. It has one 10 MW laser, a sandcaster and a missile launcher in each of its two turrets. The laser has a DAM of 24 so a roll of 1-2 give Light damage, a roll of 3-5 gives Severe damage and a roll of 6 gives Critical damage.

The old way of doing damage still exists of course, take your weapons DAM and subtract the targets DAB and use that on the damage table in the rulebook; same result.

As usual I have also added a bunch of smaller edits and updates in the rulebook.

*The damage table and the weaponry come from the Free trader design available from the downloads page.

That is all folks. Happy Halloween!

Sensors part 2

Posted in Intercept, Rules on September 25, 2018 by Anders Backman

Sensor_Operator

Stars, hide your fires; Let not light see my black and deep desires – William Shakespeare, Macbeth

We’re deep in space. Corner of no and where. You take extra care. ‘Cause we’re very much alone out here – Captain Malcolm, Firefly

In art and dream may you proceed with abandon. In life may you proceed with balance and stealth – Patti Smith

Intercept have four sensor types and five types of scans (Optical sensors can scan using Visual or IR). Each scan type in Intercept (Visual, IR, Radar, Neutrino and Mass) have their own strengths and weaknesses. To get a basic a basic understanding of how the different types actually work you should read Sensors part 1.

Scan modifiers

 

Visual

Location

Stay in the shadow columns of planets and asteroids or stay directly north of your target forcing him to scan with Sunglare. Have planets block the enemy scans of you if you know their location.

In shadow columns the Sun factor is 0 instead of the typical +6 but if your enemy is clever he will scan specifically in the shadow column using IR so, if approaching via the shadow column take your time and drift in with power off.

Approaching from the sun is another way of avoiding detection. Forcing your opponent to scan with Sunglare reduces his scan with the Sunfactor, typically by 6.

Self
Avoid thrusting unless absolutely necessary, drift instead.

Don’t thrust, specially if you have fission or fusion thrusters with their huge signatures, but even impulse or floater drives normally give off the same signature as your hull in sunshine.

Planet and asteroid sun and shadow columns

IR

Location
Approach from the sun and force the opponent to scan with Sunglare. Use fission or fusion thrusters as little as possible. Have planets block the enemy scans of you if you know their location.

Just as for Visual scans approaching from the sun will force your opponent to scan with Sunglare and IR scans too subtract Sunfactor from the scan, typically 6. This is your only option, the shadow column won’t help your IR signature at all.

Self
Turn off the powerplant using Silent running. Use fission or fusion thrusters as little as possible.

Silent running reduce every signature of yours except Visual. Your ship would only have IR(Hull) for IR, typically with the same low strength as your hull in shadows. Don’t use fusion and fission thrusters except when absolutely necessary, impulse and floaters are fine but you need to have the powerplant running to use them of course. Keep in mind that if your powerplant is off you need to power it up using your repair crew which on larger vessels can take a turn.

Sunglare

Radar

Location
Have the planet block radar scans. Keep distance to the enemy.

Radar is rarely used except when the enemy knows they are detected. Try to keep distance to your enemy as radar falls off much faster than other sensors by range. Radar is unaffected by Sunglare so coming from the sun won’t help you.

Self
Pop in to reduce signature. Works on any ship except Open frame ships.

Popping in will reduce the radar signature of your ship by 6 on all ships except open frame hulls whose signatures are unaffected by popping in. Note that if you pop in you can no longer scan (except with neutrino or mass sensor), you will also lose any tracks you have (once again except if you track using neutrino mass sensors) and finally you will lose any launched missiles, drifting decoys remain however.

Cloud chamber.png

Neutrino

Location
Stay north of the enemy forcing him to scan with Sunglare. Neutrino sensors are always subject to Sunglare, even when in planetary shadow.

Coming from the sun forces your opponent to scan with Sunglare. Sunglare reduces the scan by Sunfactor, typically subtracting 6 from the Scan. As neutrinos can travel straight through a planet Sunglare affects scans even when a planet would normally block (sun column, shadow column questions are ignored for neutrino scans).

Self
Turn off your powerplant using Silent running. This works with both fission and fusion reactors. Use fission and fusion thrusters as little as possible.

Neutrinos are only given off in detectable quantities from fission or fusion reactors and fission or fusion thrusters. So, turn off your powerplant using silent running and don’t use your fission and fusion thrusters. With these off your ship has no Neutrino signature at all and thus no chance of detection from neutrino scans whatsoever.

Elite Dangerous_20180624213851

Mass

Location
Stay away from known mass sensors, their falloff is as bad as radar so range alone might save you. Coming from the sun has no effect on mass scans, they ignore Sunglare.

Mass sensors fall off much faster than regular sensors because they rely on tidal force rather than gravity directly. Try to stay away from known mass sensors is about all you can do.

Self
Don’t use Impulse, Grav or Floater thrusters needlessly, fission and fusion thrusters work fine. Turn off floor field when drifting.

Thrusting using Impulse or Floater give off huge signatures, on par with fission or fusion thrusters for Visual and IR scans. Use them only when you absolutely must. Fission or fusion thrusters are actually fine and won’t show up on mass scans. When you are not thrusting your strongest signature comes from your floor field, turn it off when drifting. Your ship have a mass signature like a ship in sunshine when the floorfield is on and like a ship in shadow when the floorfield is off.

That’s all folks, stay cold, dark and inert.

Sensors part 1

Posted in Intercept, Rules, Science on September 20, 2018 by Anders Backman

Planet LOS in Star Wars

Space combat takes place at incredible ranges, tens of thousands of kilometers, and unlike in the movies, you won’t see anything through your window; a nuclear detonation for sure, fission or fusion thrusters as pinpoints of light maybe, the plume of a missile just before it hits you, the blinding flash from a laser hitting your ship, but aside from that nothing…

All ships carry sensors to see things around them and this is especially true of warships. All ships will have optical sensors seeing in visual and infrared wavelengths and most will also have radar. More exotic sensors such as neutrino or gravity sensors may be carried by larger or more specialized vessels.

Visual, infrared and radar sensors are mounted on the surface of the hull and can only be used when unfolded and extended, popped out as it is called in the game. Neutrino and mass sensors sees right through the hull so they can be used whether popped out or not. This make them especially suitable for military purposes as they can be used while still protected by the ships armor.

Visual

Visual scans are done with optical telescopes collecting light from visible wavelengths.

Light sources can be light from the sun reflected from the hull. How much depends on the strength of the sunlight, the area of the reflecting hull and how reflective the hull material is.

Light can also be directly emitted by a ships thrust, either the intense light from fission or fusion rocket plumes or the much fainter glow from impulse thrusters or floaters (that magic sci-fi blue glow).

The Inverse square law

The light falls off in strength as it spreads from its source, in both dimensions, if range doubles the intensity goes down as 1/2 times 1/2 or 1/4.

Infrared

Popular media usually depict space as cold but in reality the problem is the opposite, getting rid of heat is hard part and the only viable long term way of doing it is by radiating it away. Every object radiates heat, how much depends on its temperature.

Ships have optical sensors that can either look in visual wavelengths or in infrared to detect objects as they radiate heat to cool. Ships radiate enormous amounts of heat when using fission or fusion thrusters, less infrared is radiated from the power plant when running, ships also radiate a faint heat from the temperature of the hull itself.

The infrared light falls off the same way as visual light, by the square of the distance. A given ship is typically easier to detect visually than by infrared, at least when the ship is in sunlight or if the ship has a running power plant. If the ship is using fission or fusion thrusters it’s about as easy regardless of using infrared or visual scanning. What to use really depends on what you think you are trying to find, tricky.

Plotting board

Radar

Everyone is familiar with radar works; you send out radio bursts that bounce off the target and get detected as it comes back.

One problem with radar is that it falls off much faster than visual or infrared does. Radar, although invented during World War II didn’t detect the planet Venus until 1961 yet it can easily be seen by the naked eye. Doesn’t radar waves fall off by the inverse square as visual and infrared does?

Of course they do. The problem is they fall off by the inverse square both going there and coming back again, 1/r^2 going there x 1/r^2 coming back again or, 1/r^4. If this sound weird and hard to grasp think about the following analogy:

You walk at night in a forest with a flashlight in your hand. The flashlight is a powerful maglite showing you the trees out to about 30 meters.

The flashlights range depends on the power of the flashlight but also the quality and focus of the lights parabolic mirror. The light falls off going out, bounces off trees and falls off coming back again, back to your eyes, your detectors, just like a radar.

Let’s say you decide to try your car lights instead. They must be a hundred times more powerful right? And now you can see trees out to about a hundred meters, three times farther or so. Three to the fourth power (3^4) is about a hundred (81) so that terrible range fall off of radar affects flashlights and headlights the same way.

t2kdetector-640x200

Two men in a rubber raft inspect the wall of photodetectors
of the partly filled Super-Kamiokande neutrino detector (Ars Technica)

Neutrino

Neutrinos are these strange subatomic ghost particles created in fission and fusion reactions. These particles really fleeting, reacting to next to nothing. Build a wall one lightyear thick and half of them still get through. How can one ever hope to detect them with something smaller than a solar system, smaller than a planet even, small enough to fit on a ship?

What you do is you amass an enormous amount of atoms, in the hope that one neutrino might interact with one of them and then surround the mass with super sensitive detectors hoping to catch that one interaction somehow. The first detectors used thousands of cubic meters of water or chlorine as the mass and after waiting a long time they got the first signal from the sun. Imagine that, it took this enormous tank lined with super sensitive detectors sitting for months to detect a single neutrino coming from this enormous fusion reactor we call the sun.

Neutrino detectors in Intercept appear at TL-11 and assumes that some breakthrough has appeared, some resonance to exploit or some other way to make the neutrino detectors much smaller and much more sensitive, still bulky but practical. Neutrinos created in fission or fusion thrusters and fission or fusion power plants are what these detectors see. As the neutrinos leave their source they spread out, just as the visible photons for the visual scans and the infrared photons for the IR scans so the fall off is the same.

Neutrino sensors can only detect fission and fusion thrusters and fission and fusion power plants. On the other hand when they can see targets on planets or right through planets as if they aren’t there at all. In fact, a ship in the planetary shadow scanning towards the sun will be affected by Sunglare as if the planet wasn’t there at all.

Gravity with Thrust

Mass

Detecting a nearby mass seems easy. Just measure its gravitational pull on you. Not so easy. Imagine you were locked inside a small box either being a hundred km above earth and falling towards it (let’s ignore air drag completely) or being a light year away in the depth of space.

How can you detect which is case it is? How can you detect how far away earth is and in what direction? In both cases the box and you would be at rest with each other, either falling freely towards earth or just drifting in interstellar space. You could peek out of the box but that would be cheating. There is one difference that you can actually measure, being near earth means you closest point, say your toe, would be pulled towards earth a tiny amount more than your furthest point, say your nose, the difference between these pulls could be measured as a very weak force and this force would grow weaker the farther away from earth you go, a light year away in deep space and you’d measure nothing at all.

This force is called the tidal force and pulls apart parts of objects in a gravity field. The ocean water closest to the moon gets pulled towards the moon relative the water on the other side causing two bulges that move as the earth rotates. Yes that is why there are two tides each 24 hours.

Tidal force falls off as 1/r^3, double the range and the tidal force is 1/2 x 1/2 x 1/2 or 1/8 the strength. This limits the range of mass sensors but on the other hand they can see right through planets and because of the 1/r^3 falloff can scan towards the sun.

Mass sensors detect the mass of a ship directly but usually they detect the much stronger emissions from the gravitic Impulse or Floaters and also any working floorfields. This means that older low tech ships lacking floorfields and relying on fusion or fission for thrust are actually the hardest to detect.

Well, that is all for now. The next article will deal with the practical use of these sensors in Intercept. How to use them effectively and how to avoid being detected by them. Keep the solar wind to yer backside folks!

Intercept rulebook update

Posted in Intercept, Rules on July 6, 2018 by Anders Backman

Elite Dangerous_20180701172211

I have updated the rulebook with some minor changes mostly for readability. There is also a step by step example on how to achieve stable orbits added, on page 21. As always you get the rulebook, ship designs, map templates to print, ship data cards etc here, and as always it is free of charge.

Landed or docked

Posted in Intercept, Rules on July 2, 2018 by Mr Backman

Landed on planet with atmosphere

Space is empty and very hard to hide in as your ship will stick out like a beacon against all that black. Sure, getting far enough away from any sun, painting your ship the blackest of black and not using any  thrust might make you harder to see against the black but what about infrared? Sure, you can turn off your powerplant and distribute the remaining heat radiating from your ship more evenly via stealth tech, and of course not using any rocket thrust but that black space around you is only 3 degrees Kelvin, so what to do?

The best way to avoid detecting is staying away from space altogether. Dock with something big, land on an asteroid or a planet, preferably with a thick atmosphere, or hide hovering inside the swirling clouds of a gas-giant. These rule will teach you how to scan for landed or docked targets, scan while being landed or docked and finally how to perform combat between landed ships and space, in both directions. The updated Intercept rulebook including these rules can be downloaded here.

A landed or docked ship is either in the Sunside illuminated by the sun or the Darkside hidden in the shadows, both sides have their pros and cons.

Scan for landed

Landed LOS

Sunside The planet or asteroid will block half your view so you cannot see anything farther from the sun – but on the other hand those farther from the sun cannot see you either. You are lit up by the sun by so is your surroundings. If the planet has any kind of atmosphere you cannot see out at all using Visual or IR sensors, Neutrino and Mass sensors completely ignore planets and asteroids. If there’s no atmosphere you can scan using Visual or IR into any square equal to or closer to the sun than you, if there is an atmosphere you cannot scan at all (neutrino and mass scans can always scan of course). Being in the Sunside also means having to worry about staring into the sun, make sure that your Scan doesn’t touch the Sunglare column as your opponent will happily remind you.

Darkside The planet or asteroid will block half your view so you cannot see anything equal or closer to the sun – those equal or closer to the sun cannot see you either of course. You are in the shadows cast by whatever it is you are docked to or landed on, good for you. At night the atmosphere is dark so you can actually scan using Visual or IR sensors. Your surroundings will be heated from the sun so your ships infrared emissions will be harder to pick up. As usual Neutrino and Mass ignore the planet, asteroid or docked ship and can scan as if nothing was there.

Scanning for landed or docked targets

When scanning for docked or landed targets you must tell your opponent that you wish to do so and what side you scan, Sunside or Darkside as you cannot do both with the same scan. Scanning for docked or landed makes your Sense task harder, how much harder depends on what you scan but the Sense roll will always be harder so don’t scan for landed or docked willy-nilly.

Reveal your Scan as usual, strength, size etc, tell the opponent that you want to scan for docked and landed too, tell if you Scan for Sunside or Darkside. Opponents ask you the usual questions:

  • Does the Scan touch Sunglare? Works as normal, subtract Sun factor from your Scan strength the Scan touches the Sunglare column, but not if your ship is in planet or asteroid shadow.
  • Does the Scan touch Suncolumn or Shadowcolumn? Works as normal. If it touches Suncolumn you must say if you are in the shadow column or not, and if it touches Shadowcolumn you must say if you are in the Suncolumn or not, if it touches both you must say if you are in either.
  • Is part of your Scan blocked by the planet? Works as normal. Note however that you can only scan squares for Sunside of they are equal to or closer to the sun than you and you can only scan Squares for Darkside if they are farther from the sun than you.

Then roll a Sense task, use the highest target number for all applicable targets within the Scan. If both a planet and an asteroid are inside the scan you must roll 9+ if you wish to look for landed on both but you only need to roll 8+ if you only search the asteroid.

  • Sense 6+ If scanning normally for ships in space
  • Sense 7+ If scanning for docked ships
  • Sense 8+ If scanning for ships landed on asteroids
  • Sense 9+ If scanning for ships landed on planets
  • Sense 10+ If scanning for ships hovering in gas giant atmospheres

Ships in space (ie not docked or landed) reveal Contact info if the Signal is 0+ as usual, landed or docked ships however, never reveal Contact info, either you saw nothing or you get a Tracked result.

Landed or docked Signatures

Landed side These effects only apply to the ship landed or docked.

Landed side

Atmospheres These effects apply when scanning from the planet as well as to the planet, both directions reduce the Signatures. Note also that ships landed in the Sunside of a planet with atmosphere cannot scan Visual or IR at all, radar, neutrino and mass work fine.

Landed atmosphere

Aerobrake signatures An aerobraking ship will shine brightly in both visual and infrared, the more so the faster it goes and harder it brakes, if you don’t believe me check out the video.

Aerobrake glow

Aerobrake signature

Scanning when landed or docked

Docked or landed ships are Sunside if unrolled and Darkside if rolled, if the ship you are docked to roll your ship become rolled too. Sunside can only see squares that are equal to or closer to the Sun, Darkside ships can only see squares that are farther from the sun. This mean that if the enemy cannot see you then you cannot see them either.

When the target ask Is part of your Scan blocked by the planet? You must tell him which squares that are blocked and this pretty much guarantee that he will know that you are landed and what side. To counter this avoid when Sunside and thus unrolled only scan squares that are equal or closer to the sun and when Darkside and thus rolled only scan squares that are farther from the sun. This means that you should avoid scanning boxes of the same row as you are in or only do smaller 1×1, 2×2 or 3×3 square scans.

If the planet you are landed on has an atmosphere, including when hovering in a gas giant atmosphere) the atmosphere absorption modifier is applied to your scan strength before revealing it to your opponent. That is all there is to scanning from landed or docked.

Combat between landed and space

So, one can scan for landed or docked and one can also scan when landed or docked, this inevitably lead to combat between landed / docked and those in space. Ships can only be attacked if they are tracked of course, which even simpler for docked or landed targets as they never reveal Contact info, it’s tracked or nothing.

Docked ships have the same status of thrusting or drifting as the ship docked to, landed on asteroids, planets or hovering in gas giant atmospheres are all treated as drifting. All other effects of being landed depends on the atmosphere of the planet.

Beam weapons suffer PEN and DAM reductions and negative hit DMs from the atmosphere, worse the thicker the atmosphere is and particle accelerators double these modifiers making them nearly useless in all bit the thinnest of atmospheres.

Beams through atmosphere

Missile weapons must have airframes to be used in an atmosphere at all. They have a max speed when entering or leaving an atmosphere and when entering the atmosphere their speed is reduced before determining PEN, DAM and hit DMs.

Missiles through atmosphere

Yes, these rules may rarely come up in scenario play but whenever the subject arise it’s good to have it answered. It will however crop up all the time in roleplaying situations.

Players “Can I see the smugglers ship on the runway from orbit?”

Referee Checks what signature the ship would have using these rules “Yes.”

Players “Can we shoot it?”

Referee Sighs “Eh, I guess” (watching his complicated scheme go up in smoke ‘land in jungle nearby – sneak into the smuggler ship and steal it – weird cross between a tiger an crocodile enter the cargo bay – fight ensue – smugglers alarmed – another fight – ref get to test new cover system’).

Intercept movement tutorial

Posted in Intercept, Vector movement on July 29, 2017 by Mr Backman

Vector movement, a scary term to some, is the way ships and missiles move in Intercept, it is also happens to be the way real spaceships move. Movement in Intercept is done in three simple steps; Drift, Turn and Thrust. Drift can be done in any order as it is entirely automatic, Turn and Thrust are done in reverse initiative order ie the ship with the worst initiative goes first and then the second worst and so on. Untracked ships do Drift, Turn and Thrust in secret, after all tracked ships are done.

Facings closeup smaller

Directions and facings

A ship is always facing in one of 8 directions. Draw the ship as a pointed arrow in the direction of its nose, typically but not always in the direction it thrusted. The direction it is moving has no effect on the direction its nose faces.

Movement sequence

Initiative is based on higher steps of turn from the Pilot task
Turn and thrust is done one ship at a time, reverse Initiative
You may only thrust to your forward facing arc
Rolling cost 3 steps of turn
The movement sequence consist of Drift, Turn and Thrust. Do Drift for all Tracked ships and missiles before Turn and Thrust. Turn and thrust is done in reverse Initiative order, worst Initiative goes first, best goes last, declare any missile launches when your ship moves. After all ships have Turned and Thrusted its time to do missiles, in reverse Initiative order too. Missiles ignore turning as they can thrust in any direction.

aMove0
Drift
Look at your ships last move and repeat it, draw a small cross where the new position would be. This is called your Drift square and if done right your Current position should be exactly midway between your Drift and your Past (except for gravity effects, see page 16). Perform drift on all tracked ships at the same time, before any turning or thrusting, there are no choices involved so the order doesn’t matter. A stationary ship would have its drift, present and past in the same square. Take care to keep the ships facing when doing the drift as facing and movement direction are totally independent in Intercept. Aerobraking is done at the end of Drift, see page 18-19 for details.

aMove2
Turn
How many steps of turning a ship can do depends on the Pilot task result but Untracked ships can turn up to 4 steps without a Pilot roll. Turn your ship up to the number of steps, left or right, or spend 3 steps to roll the ship. Look at the firing sector diagram in the combat section to bring your weapons to bear on the enemy.

aMove3
Thrust
Each ship does its Thrust right after turning and can only thrust into squares in its forward facing arc as show in the picture above, there is no strafe thrust or reverse thrust. A ship may also elect to drift and not thrust at all. Drifting makes a ship easier to hit but also better at defending itself.

aMove complete

Completed movement
This is what your completed move will look like, the thin x marks your drift position. After moving around with a ship for a while it will become second nature to you, it’s much easier than it seems. Ships that are Untracked may assume that they always have 4 steps of turning to use ie they can turn in any direction and they don’t need to roll a Pilot task to do so.

Well, that’s all folks, fly safe.

Traveller 40th anniversary

Posted in Intercept, Traveller on July 22, 2017 by Mr Backman

Traveller the roleplaying game is celebrating its 40th anniversary today so I took the opportunity to update rules, maps, ship design system etc to the latest version today.

Did you know that you can use Intercept with your Traveller characters with no conversion needed, at least if you use the classic system or anything similar to that? And that Intercept has premade versions of Freetrader, Fartrader, Subsidized merchant & launch, Scout courier, Survey cruiser, Patrol cruiser, Modular cutter, Mercenary cruiser, Close escort & launch, System defense boat & Jump shuttle, Fleet escort, Azhanti cruiser & Rampart fighter? Here! The rulebook, maps etc are available here.

Intercept is not Traveller but is compatible with it, at least at higher tech levels. High Guard and Striker weregreat sources of inspiration for the design system and what to focus on and what to change (GURPS Vehicles 2ed should also be mentioned here). I have been playing Traveller since 1978 with lots of different people, including my kids as they grew up. Many thanks to Marc Miller, Loren Wiseman, Frank Chadwick and of course the brothers J Andrew Keith and William H Keith Jr!

Travceller 40th anniversary

Traveller, Intercept and the banner of the Third Imperum on my balcony July 22 1017