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.

Radar

Plotting board

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

Cinematic movement

Posted in Films and TV, Intercept, Vector movement on April 1, 2017 by Mr Backman

I have recently come to the conclusion that not many people find Vector movement to be neccessary or even preferrable for a space combat system. Less and less people read actual Science Fiction, ie something not based on films, games or comics, so it gets harder and harder to sell the idea that vector movement is how spaceships move and they should therefore like it.

So, today I have decided to go with the flow and embrace the more cinematic style of space combat. Battles from SciFi universes such as Star Wars and Star Trek could run battles using the Intercept rules with double blind hidden movement, fully deterministic, logarithmic values etc without foregoing their popular cinematic movement style.

What then IS a proper cinematic movement system? I have decided to break down the two most popular settings, Star wars and Star Trek and see how we could emulate that in our game:

Star Trek
I have complained about the various scientific inaccuracies of Star Trek but failed to mention its strengths; Star Trek shows us a positive and humanistic view of the future. Enterprise and its brave crew aren’t on a mission to subjugate planets and aliens, they are there to explore and help and always keeping in mind the prime directive, never interfere destructively. Star Trek also gave us the female perspective with Lt Uhura as a near equal on the bridge yet still able to express her female side with her short hemlines and sensuality. Star Trek also stress how important emotions are to us humans, always trumping cold logic. Kirk wins by persevering over staggering odds despite Spocks logic telling him his efforts are futile. We can learn something from this as politics is often too much ruled by logic and hard facts ignoring the very thing that makes us unique in the world; our emtions.

Star Trek ships use subspace warpdrives to quickly move from system to system. There are cases when they have battled during warp but this is too different to regular combat and will be covered in a future post. Star Trek ships always move with the nose in their forward direction. Some kind of drag seems to be in effect as ships with damaged impulse drives tend to slow down and ultimately stop. Top speed vary little between capital ships as is eveident from their inability to outrun each other. The Wrath of Kahn end battle has Kirk using thick clouds of a Nebula to turn the tides on Kahn instead of merely outrun him. The ability to turn seem more or less the same, regardless of speed and ship size.

Star Wars
I have often critizesed Star Wars for being a fantasy story disguised as Science Fiction. This may or may not be true as all Science Fiction is really nothing but some other literary genre in disguise (Blade runner is crime fiction, Barbarella and Zardoz is soft-porn etc). What Star Wars did to Science Fiction is to put religion as center stage. Many know me as a fervent atheist but what is atheism exactly, if nothing but a different faith? All humans need to believe in something and to hold something higher than himself, to serve and strive for. Star Wars also show us that not everything can be settled by a majority vote; there are issues and questions that must be handled by wise and spiritual elites, far better at judging changes in tradition and culture. Jedi knights show us a solution to the problems facing todays democracies; the lack of spirituality and disregard for tradition.

Star Wars ship jump between solar systems very much like the Traveller jump drives but no combat seems to occur while in jump space. Star Wars ship seems to have vastly different top speeds depending on size where smaller ships outrun bigger ones. Star Wars ships turn slower the faster they go as is evident if one analyze the dogfights in Star Wars Episove IV.

Star Trek cinematic movement rules
Use as much of the Deterministic optional rules as possible to get the feeling of Kirk and Klingon in a battle of the minds. It is especially important to use the deterministic ruls of Initiative where the Initiative goes to the ship which ‘skipped’ more steps, see the Deterministic combat rules for details on this.

Ships should note their speed and can move to any square in their forward arc. Turning is done anywhere during movement.

All ships can turn 4 steps each turn regardless of size, -1 step if Hull or Crew has Light damage, -3 if Hull or Crew has Severe damage. No turning if Hull or Crew has Critical damage.

Ships can increase or decrease speed by Acc, top speed is 6 regardless of Size, Acc etc. Ships lacking thrust reduce speed by 1 each turn until stopped.

Star Wars cinematic movement rules
Do not use the deterministic rules as Star Wars portray battles as individual skill rolls. Give your hero characters lots of skill bonus.

Ships should note their speed and can move to any square in their forward arc. Turning is done anywhere during movement.

Ships roll Pilot tasks vs Size as usual noting the steps of turning. Reduce turning steps by one for each full multiple of Acc in speed. Ships moving at top speed cannot turn at all.

Ships can increase or decrease speed by Acc, top speed is Acc * 4. Ships lacking thrust reduce speed by 1 each turn until stopped.

Well, that is all folks, get out and enjoy this beautiful April fools day!

Version 3.4.3 update

Posted in Boardgames, Design system, Intercept, Other vector movemet systems, Traveller on December 11, 2016 by Mr Backman

Board and counters

Vesta acquisition. In response to the verbal from the autopilot, Dieter Ulans flipped his datavisor in front of his eyes and prepared to take direct command of the massive ring of lasers and reaction engines that was Hercules. He hit the juicer button and felt the rush as the drugs began to wash into his veins. “Com’monn jockey juice!” he whispered and then began to croon: “All my thoughts of you, you, you — all that I’ve sought is you, you, you.” The tiny green symbols on the datavisor began to zip past his eyes at an increasing speed.

From the rulebook to Battlefleet Mars 1977 – Essentially the Expanse setting but 39 years before it aired.

Rules

There are lots of changes all over the rules, too many to mention. Sections have also been rewritten, gotten new or updated illustrations or have been rearranged, to clarify and simplify without actually changing too much.

As always, read the front page to get a feel how the game works. Then, read pages 2-3 which cover tasks and initiative, very important to grasp. From then on, simply start playing a turn and read as the turn progresses, the rules are written in turn sequence order.

You can download it all here, as usual, with the updated designs, maps etc.

Tasks

The task system has gotten a facelift and a slight change to what Miss margins give what result. All tasks are now highlighted in red in the table columns to make them easier to find, they are also duplicated on the four reference pages at the back. All degrees of success or failure are now three points wide:

  • Very Good You rolled at least 6 points above the target number.
  • Good You rolled 3-5 above the target number
  • Fair You rolled 0-2 above the target number
  • Miss You missed by 1-3
  • Bad You missed by 4-6
  • Very Bad You missed by 6 or more 

Movement

The movement rules are basically the same as before but rewritten and clarified with step by step illustrations on how movement is performed. The section on plotting has also been clarified and with a detailed example illustration showing all aspects of plotting.

fractional-thrust

Fractional thrust Ships don’t come with Thrust in increments of whole Gs, fractions in increments of 0.25 Gs allow the ship an extra G on certain turns of every group of four turns. The mapsheet holds helpers for this and there is also check-boxes for fractional thrust, loaded and unloaded, on the ship Datacard too. All ready-made designs have these already filled in for you. A ship with 1.25 Gs of thrust would thrust 2 G on turn 1 and 1 G on turns 2-4, 2.5 Gs of thrust would thrust 3 G on turn 1 and 3 and 2 G on turns 2 and 4. A ship with 0.75 Gs of thrust would thrust 1 G on turns 1, 2 and 3 but cannot thrust on turn 4 of every group of 4 turns.

Free traderDatacard fractional thrusts

As damage to Thrust and Power affected how many Gs a ship could thrust this has been changed too, so you don’t have to recalculate what fractions to use as you get damage. Now Thrust and Power damage affects how many turns in a row you are allowed to thrust. All, 2 turns , 1 turn or not at all for No damage, Light, Severe or Critical damage. Plotting rules teach you to draw a circle around your ship whenever it drifts and thus reset the clock on thrust.

Sensors

The fundamentals of the sensor rules remain the same, just clarifications and better examples. The only changes I can think of is that you no longer can use your Visual/IR and Radar sensors when popped in. On the other hand, ships may now pop in at any time during a turn as long as they haven’t used their weapons yet. Ships lose any tracked enemies and any launched missiles when popping in but as you know the vector and position on your targets when they were tracked reacquiring them should be fairly easy.

Oh, one more thing. Intercept now allow 2×2 scans, 2×2 square scans are +2 (+4 for radar), 2×2 boxes are -2 (-4 for radar). I didn’t allow them before because they didn’t have a clear center but showing where your scan is located should pose no problem anyway.

Map coordinate legend

The plotting rules now teached how to refer to boxes and sqaures on the map, using the legends on the map. To efer to the top left box of the map, say “Ay-one”, to refer to the bottom left square of the box where the latrge planet is in say “Dee-six one-five”. Always use column-then-row for the boxes followed by column-then-row for the individual squares.

Combat

The combat section has been rewritten and lots of die modifiers have been removed or baked into other rules. How much a ship thrusts no longer affect how hard they are to hit, we simply give a +2 DM on attacks, and defense when  drifting.

Underpower When a ship didn’t have enough power to use all their weapons when thrusting or drifting we previously used two DMs, peculiarly placed low on the Datacard and was often forgotten (I admit to cobbling it in wherever there was room).

Freetrader underpower ratings

Now, Underpower is one of All+, All, 2 turns, 1 turn, No fire, ships have separate Underpower ratings for Thrusting, Drifting or Jump prepping (more on that in the optional hyperspace rules). When a ship has Severe damage in its power location its Underpower rating is one level worse, All+ becomes All, All becomes 2 turns and so on.

Damage

Damage has changed considerably in this version. Ships now have only one DAB (Damage ABsorption) rating for the entire ship instead of one per location, ARM (for ARMour) is still per location and sometime even have two values, popped out / popped in for Surface damage, full power / silent running for high powered power locations representing their vulnerable heat radiators.

Penetration and Damage tables

How do we handle different damage at different locations then? We have three separate columns on the damage table, one for Hull, one for Crew, Core and Power and one column for Surface and Thrust.

Aerobraking & landing

I seem to rewrite the aerobraking and landing rules once every two weeks or so but now I have something that I feel I’m done with as it is fairly simple yet contains everything I want it to do. Docking and ramming has been moved to the optional rules as they tend to be used more rarely. I have increased the safe speeds for aerobraking somewhat so they become more useful. New illustrations and two examples help clarify things. there is even a little section dealing with your ships signatures when landed and how your sensors work through and atmosphere. Yeah, landing on the day side of a planet with atmosphere will make you harder to scan but your Visual/IR sensors will be blind from the bright atmosphere.

Optional rules

Campaign rules If you want to play a series of Intercept scenarios and have your crews and/or entire navy improving is skill from experience this is for you. The rules merely deal with how to track skill improvements but also skill loss from crew damage. There are also some bare bone outlines of scenarios to help you with ideas. This system is what we use at work when playing and interconnected series of space fights.

Redlining Have you ever wanted to pull all the safeties as captain Phillips did when Somali pirates tried to intercept him, or yell at your engineer ordering him to once again do the impossible? In other words, have you ever wanted to redline your engines?

You decide if you want a 50% boost to your thrust this turn or doubling it for a turn, the latter is of course more dangerous. There is a considerable likelihood that your thrust location will get a CD (Continuing Damage) ie ‘fire in the engine room!’ and you may even risk damaging your engine. Redlining, as well as powering up from silent running and the usual jury-rigging of battle damage is done by your trusty Repair Crew.

Jump distances for planets and asteroids

Hyperspace The rpg Traveller has a faster than light system that works by travelling far away from any planet, jumping into hyperspace, spending about a week there and exiting somewhere else parsecs away from where you started. I have shrunk how far one must travel to safely jump to fit planet and safe jump onto an Intercept mapsheet. There are some fairly detailed rules about how to jump, fuel use, astrogation, misjumps etc and where you will end up. In my system, all jumps have you end up somewhere, near a gas giant, planet or asteroid, even when you misjumped into an ’empty’ parsec hex in the original Traveller.

If you are playing a Traveller campaign I suggest you not only replace the space combat and starship movement rules with Intercept, replace the hyperspace rule too.

Design system

There are tons of changes to the design system too. Most importantly I think you get all the important design spec data in one place. As shown by this part from the Free trader design spreadsheet available in both InterceptBundle and Designs.

Ship stats for the Freetrader

Three little orange dots appeared on the screen. Look at him — blowing out decoys even though he knows we’re out of maneuver — that Kolnichok, grinned Dieter. So which one is you, Joey, and which are the aluminum balloons? (Seven dots grew on the screen, all had slightly different vectors.) Now you know my heater can take you in one flash and you also know that one zap is all I’m going to get. And if I take it you’ve got a perfect excuse to blow me up for the honor of the company rather than recapture valuable property for the accountants. So what’s it going to be? I think you shot off too many balloons too early Joey — cause the other ones aren’t making the course correction you just did. Ain’t that you, Joe?

Ulans squinted and tapped his foot.

From the rulebook to Battlefleet Mars 1977 – notice the green grid tactical maps where one could play out space battles with vector movement, in 3D no less, in 1977!

battlefleet-mars

The contents of SPIs Battlefleet Mars boardgame from 1977.