Traveller Tuesday: Sand

The past two game sessions in my Traveller campaign were a playtest of aspects of the new 2e space combat system, crossed with some house rules. And like what always happens when I meet a rules system, I found that some things didn't make sense, so I've decided to change them -- either for verisimilitude or for game balance.

This is probably going to part of a series on Space Combat.

My use of Traveller setting and dress falls under
fair use guidelines for both Mongoose and Far Future Enterprises.

Range
The very first thing that I did was to change the range and range modifiers to sandcasters. Instead of having a maximum range of Short (up to 1250 km, which just seems really excessive for what is essentially a "space depth charge"), their maximum range is now Close. However, the no longer have a range penalty for being used at Adjacent range, which is helpful when using Pebble rounds to shoot at boarders or missiles that got past point defense.

Implementation
The rules-as-written way to use sand is as a reaction -- your sensors indicate the enemy is powering up a beam weapon and you fire sand to intercept. And this is fine if there's a specific attack you really, REALLY want to block.

But I also think you ought to be able to put up sand as a preemptive barrier between you and your enemy. If that's the case, then your Gunner (Turrets) skill roll becomes the number to hit your ship; otherwise they hit your sand cloud instead. I've been running it this way for a while, but I figured it ought to be written down.

Blocking
Sand clouds last for one turn. If they are hit, they ablate/vaporize; it they are not hit, they drift apart from the initial canister detonation that causes their spread.

There has been much discussion about whether or not sand should block plasma, fusion, and particle beams. After going back and forth on it, and talking about what I want from it vs. how the various beams work, I have come to the following conclusion:

• Sand reduces laser beams at full strength (1d6)
• Plasma and fusion beams are reduced at half strength (1d3)
• Particle beams are reduced at one-quarter strength (1d2)

A hit by any of these weapons that penetrates it will clear a hole through the cloud, effectively dispersing it. This qualification is necessary, because a triple sandcaster throws out what is essentially a 3d6 cloud, so a cloud with maximum effectiveness (18) will not be cleared away by a strike from a minimum-strength (3) particle beam.

Chaff
I also feel that sand is more than just "sand". Given the way sandcutter rounds work (using electromagnets to disperse sand clouds), it's obvious that sand is metallic and magnetic in some manner, which means it ought to have a radar cross-section. This sounds an awful lot like chaff, which is under-represented in the game anyway.

I like the notion that defensive sand, in addition to acting as a light absorber, also works to block sensors -- most of which are light-based -- and to confuse the sensors (also light-based) of smart missiles.

• Sensor Baffling: A sand cloud which has not dispersed acts as a diffuse shield against EM sensors. The effect of the Gunner (Turret) roll acts as a DM against all sensor checks across the cloud. Sand can be used in this manner to break sensor locks. However, this works in both directions -- a cloud your enemy can't see through is one you can't see through, either, unless you have better sensors. 
• Missile Blocking:  A non-dispersed sand cloud affects the sensors of all missiles. "Dumb" missiles shot on a straight ballistic course are not affected. (More on those missiles in a follow-up post.)

Shooting Down Missiles

http://orbitaldebris.jsc.nasa.gov/protect/impacts.html

Hiding on p.50 of Mongoose High Guard is the note that sand canisters can be used to shoot down missiles, if said missile has been launched from at least medium range. I interpret that to mean "If the missile will hit in the same turn that it's launched you can't shoot it down with sand, but if there's a delay of a least one round, you can intercept it."

And since most of us have seen what a paint flake traveling at orbital velocity did to a space shuttle window, you can imagine what a shotgun-like spread of metallic sand will do to a missile -- especially when you add the velocity of the missile and the intercepting sand particles.

Your Objections Anticipated
Some of you are no doubt saying, "But Erin! Haven't you just combined Sand, Pebble and Chaff into a single canister?"

Indeed I have. Sand is neat stuff.

And I'm pretty sure I've shown how I reached that conclusion: chaff is metallic, and sand is metallic or else it wouldn't be affected by sandcutters; ergo, it likely has offensive uses. And since I've shortened the rage of sand cannisters to Close and the difference between sand and pebble is 1 point vs 1-3 points of damage, I feel this is not unbalancing.

You are, of course, free to argue.