Supplement Four
SOC-14 5K
Excellent idea.
Heat & Stealth.
- Thread starter Magnus von Thornwood
- Start date
Excellent idea.
salochin999
SOC-13
A stationary ship on picket duty could rotate maybe and get a full spherical picture that way? That's quite a neat picture actually - a screen of picket frigates move out to advance positions and start spinning and only then does the main fleet follow. Or a similar idea but with drones.
Or of having multiple wide angle sensors, as implied in MegaTrav.
Probably. 20% of your free trader is an awful lot of space. I suspect the various sensor arrays occupy much of that.
My opinion: free traders have the least-capable, most minimal sensors of all ships, on par with some of the small craft. I would not want to use one to search for anything.
In order to get a spherical scan, a "controlled tumble" should manage to cover every part of the sky not blocked by another object.
In order to get a spherical scan, a "controlled tumble" should manage to cover every part of the sky not blocked by another object.
Timerover51
SOC-14 5K
For passive Infra-red, you would just need something similar to a passive sonar array, with no need to tumble. Just mount a slightly more than half of a hemisphere shaped array of passive sensor elements on the nose and tail, and have it set for a high sampling rate. A passive sonar dome basically gives you a 360 degree detection zone beneath the bottom of the ship.
As for a 360 degree air search, that is pretty straightforward, as most naval combatant ships have that capacity for radar air search. Adapting those to space use would not be that difficult, in the sense that is engineering. Your problem is if you want a long-range on the set, like several thousand kilometers, as a minimum, you are going to need a pretty large antenna to have a reasonable detection chance, and it is going to have a slow rate of scanning. You could go to something like a phased-array setup, but that is going to take up a lot of the surface of your ship, be extremely expensive, and cover a limited frequency range.
Quite a few countries make laser detection gear for tanks, so it is not that complex or space consuming, but you would need 6 external detectors as a minimum, depending on the configuration of your ship, and again, they are only going to be good for a specific spectrum, generally somewhere in the Infra-red. If someone is using a different spectrum, your detector is useless.
I will have to dig out my MegaTraveller stuff and see what Tech Level this incredibly comprehensive active and passive EMS equipment becomes available, and what the cost is. It would be possible with current technology, in fact probably 1970 or so Tech, but it would not be cheap, would be demanding a lot of ship volume, and the outside of a ship is going to resemble a radio and radar antenna sales lot. Maintenance is going to be an absolute nightmare, and cost like crazy.
Timerover51
SOC-14 5K
My apologies to you. I should have phrased it with respect to the authors of MegaTraveller. There is a far amount in MegaTraveller with its "gosh-wow handwavium" that my "willing suspension of disbelief" does not willingly suspend my disbelief.
Timerover51
SOC-14 5K
Looking at the Referee's Manual,page 70, at Tech Level 10, this piece of equipment has a mass of 2 kilograms, requires 20 kilowatts of power, has a volume of 4 liters, and cost 400,000 credits. That is for a range of 5 kilometers (distant). And it does all of the above. Think about that for a minute or two.
Looking at the Referee's Manual, again page 70, the same specifications for very distant, i.e. 50 kilometer range. The MAXIMUM range on the passive array, which at Tech Level 10 weighs all of 250 kilograms, is INTERSTELLAR OR 2 Parsecs. A Parsec is 3.26 light years, so the maximum range for a EMS passive array is 6.52 light years. Aside from any data collected being 6.52 years out of date, this item can actually discriminate between the system Sun and a ship in the system?
My "willing suspension of disbelief" with respect to the MegaTraveller design sequences shatters again. What really bothers me is that MegaTraveller takes some of the systems back to Tech Level 5 and 6, where Real World data existed for a starting point. That, and according to the Manual, it is possible to jam a FM radio station at a range of 5,000 kilometers on a planet, presumably the size of Earth. FM is line-of-sight, unless you get a weird atmospheric bounce. Again, think about that a minute.
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GypsyComet
SOC-14 1K
MegaTraveller vehicular tech is a combination of extrapolation from Striker, and the DGP crew's desire for Traveller to be, as you put it, "gosh wow". The sensor section in MT is particularly blatant in the latter department, especially in the weird science section.
The Neutrino sensor, a tiny installation, must be some amazing tech to be able to differentiate ship power plants from the local stars in real time when our current neutrino sensors are the size of the cargo bay and see so few neutrinos per month that the monitoring scientists can practically process each individual neutrino before the next comes in. A supernova event caused 19 detections *total*, for example.
Don't even get me started on the MT Densitometer.
NOOOO! Thinking is bad! It takes you to the bad place, where you start having doubts and suspicions! You must trust the authors!
Seriously though, it's just sandcaster tech: another far future impossibility that we tolerate in the name of game play. They need tech that does X, they need it to be usable in a vehicle, and small enough to not take too much space from weapons and other needs, and to fit neatly into a progression chart. So voila, it is. Us schnooks who don't know enough about physics to question whether something is going to be possible two tech levels from now, we never suspect a thing.
I for one haven't the foggiest notion about how much room a 5 km radar or ladar or what-have-you take up individually in the first place, so folk like me aren't likely to wonder if future technological improvements couldn't actually make them small enough to fit in that space. For those who do know - well, there are a lot worse violations in the game, so it's just yet another "hold your nose" thing. That's a rather long list.
No. Despite it being called interstellar range, when you do the calculations you only end up with something that can sense a ship at a range of a couple or three light-seconds. I figure maybe it can pick out the radio emissions of a major inhabited planet at two parsec range, something on that scale. It'd be useful to the Scouts to be able to tell if a neighboring star harbored a technological civilization. Or maybe the Imperium's truth-in-advertising regulations are very weak.
That one depends on the gamemaster being knowledgeable about how radio works. MegaTrav - and Striker - use the range as an indication of the unit's broadcast power. Where the jamming unit is ground-based, most of the game activity is too. A 5000 power jammer pretty well dominates the battlefield out to the horizon unless you have a 5000 power radio on the battlefield, in which case it's a question of which one you're closer to. Where they failed was they should have mentioned that the jammer only works to the horizon; they just assumed that would be where the action was and didn't consider folk trying to claim the divisional HQ was being jammed because of a high power jammer well over the horizon.
That's a bit of a shame because the control of radio (and radar) can potentially be an interesting battle all by itself, with distant commands sending craft to high altitude to broadcast or jam and then trying to defend them from enemy long-range missiles and other attacks.
salochin999
SOC-13
I agree with that in principle although I think it can be more interesting in a game if you start from reality and then work backwards to what works best in a game as that process can throw up some interesting possibilities you might not otherwise have thought of.
Given the shape of ships I don't think all round real-time sensors would be that easily done or rather the ways it could be done might make for an interesting side track in a game some way or other, for example:
a ship studded all over with sensor arrays like bubble wrap would be an interesting visual (but what about streamlining?)
a ship with sensors on extendable booms could make for an interesting repair encounter especially if pirates attack while a player is hanging onto a stuck boom
a ship with one set of front-facing sensors and a second rotating array around the middle of the ship might make interesting terrain during a space walk
etc
This is used in both Star Cruiser and the TNE board games. It's a great element to use, and I found it builds the game when both sides manoeuvred first to find out what the other side had where.
Of course, that depends on what one presumes can be seen at what range. Is a target lock-on inevitable given sufficient time for a firer to gather data, or is it still going to be chancey right up to when the button is pushed/trigger pulled?
Travellerspud
SOC-12
Very Crude Draft....
# of Sensors (w/o paying extra - these "come with the bridge cost")
small craft/fighters: 1 note: commercial small craft range limited
merchant/commercial: 1/face (4 total) note: range limited
military:
0-1000 dTon 3/face
1k-10k dTon 5/face
10k-100k dTon 10/face
100k+ dTon 50/face
to operate sensors (any number - they are all hooked to one master board on the bridge, etc) requires an Operator (who makes any required rolls). To be an Operator requires one of the following skills: Navigation, Pilot, Computer, Communications, or Electronics. If an Operator has none of these skills, roll with a DM of -4 (note: a skill of 1 in any of the required skills makes basic checks automatic, but even an unskilled operator has a 50% chance of succeeding on a basic sensor check)
Sensor Check 3+ (DMs: Navigation, Pilot, Computer, Communications, or Electronics. Intelligence 10+ gives a +1)
mods for range, atmosphere, more difficult checks, etc TBD (I think MgT has these)
Sensors are damaged (restricted by facing) whenever a hit is made, and on the damage roll a die is;
missile/missile bay ... 6 (1 sensor)
lasers ..................... 6 (1 sensor)
Energy Weapons ...... 5,6 (1 sensor)
P/A Weapons ........... 5,6 (1 sensor)
Nuclear Weapons ..... 3,4,5,6 (each does 1d6 sensors)
eg; a hit is made with a nuclear weapon , and the damage roll (2d) is a 4 and a 6 ... so 2d6 sensors are destroyed on that facing.
note: this "rewards" hits that do little or no damage, vs. those that do damage - invert the numbers (1,2,3) to reverse this.
note: IMTU, weapons do the following on a hit;
Nuclear missile: 10 damage rolls + 2 radiation rolls
HE missiles: 2 damage rolls
Missile Bays: 6 damage rolls (IMTU these are large missiles called "torpedoes" carrying enough fuel to get to long range...a nuclear "torpedo" does 20 damage rolls + 3 radiation hits).
note: nukes "scrub" a ship very quick IMTU....if they do not outright destroy it...but beware any non-Imperial that uses them (mostly pirates vs. SDB's)
only the first roll of each of the above counts as a "auto critical" (ie- rolls on critical table for each weapon level above hull size). If you get a "critical" result on the damage table, it still counts.
note: IMTU there is a "point blank range" (0-10,000 km) where computers can be ignored (say for fighters) and targeting can be "visual", gunnery skill counts, etc. Turret missiles can only fire at this range (offense or defense). Bay missiles fire at any of the 3 ranges. Fighters can deliver nuclear turret missiles and do substantial damage (if they survive the approach). Range progression is "long" (~1,000,000 km to max range), "short" (~10,000 - 1,000,000 km), "Point Blank" (~0-10,000km) so depending on the starting range, it will take fighters 1 or 2 turns to get to "Point Blank" range (assuming their side gets initiative each round).
# of Sensors (w/o paying extra - these "come with the bridge cost")
small craft/fighters: 1 note: commercial small craft range limited
merchant/commercial: 1/face (4 total) note: range limited
military:
0-1000 dTon 3/face
1k-10k dTon 5/face
10k-100k dTon 10/face
100k+ dTon 50/face
to operate sensors (any number - they are all hooked to one master board on the bridge, etc) requires an Operator (who makes any required rolls). To be an Operator requires one of the following skills: Navigation, Pilot, Computer, Communications, or Electronics. If an Operator has none of these skills, roll with a DM of -4 (note: a skill of 1 in any of the required skills makes basic checks automatic, but even an unskilled operator has a 50% chance of succeeding on a basic sensor check)
Sensor Check 3+ (DMs: Navigation, Pilot, Computer, Communications, or Electronics. Intelligence 10+ gives a +1)
mods for range, atmosphere, more difficult checks, etc TBD (I think MgT has these)
Sensors are damaged (restricted by facing) whenever a hit is made, and on the damage roll a die is;
missile/missile bay ... 6 (1 sensor)
lasers ..................... 6 (1 sensor)
Energy Weapons ...... 5,6 (1 sensor)
P/A Weapons ........... 5,6 (1 sensor)
Nuclear Weapons ..... 3,4,5,6 (each does 1d6 sensors)
eg; a hit is made with a nuclear weapon , and the damage roll (2d) is a 4 and a 6 ... so 2d6 sensors are destroyed on that facing.
note: this "rewards" hits that do little or no damage, vs. those that do damage - invert the numbers (1,2,3) to reverse this.
note: IMTU, weapons do the following on a hit;
Nuclear missile: 10 damage rolls + 2 radiation rolls
HE missiles: 2 damage rolls
Missile Bays: 6 damage rolls (IMTU these are large missiles called "torpedoes" carrying enough fuel to get to long range...a nuclear "torpedo" does 20 damage rolls + 3 radiation hits).
note: nukes "scrub" a ship very quick IMTU....if they do not outright destroy it...but beware any non-Imperial that uses them (mostly pirates vs. SDB's)
only the first roll of each of the above counts as a "auto critical" (ie- rolls on critical table for each weapon level above hull size). If you get a "critical" result on the damage table, it still counts.
note: IMTU there is a "point blank range" (0-10,000 km) where computers can be ignored (say for fighters) and targeting can be "visual", gunnery skill counts, etc. Turret missiles can only fire at this range (offense or defense). Bay missiles fire at any of the 3 ranges. Fighters can deliver nuclear turret missiles and do substantial damage (if they survive the approach). Range progression is "long" (~1,000,000 km to max range), "short" (~10,000 - 1,000,000 km), "Point Blank" (~0-10,000km) so depending on the starting range, it will take fighters 1 or 2 turns to get to "Point Blank" range (assuming their side gets initiative each round).
salochin999
SOC-13
@Travellerspud
It does seem like sensors could be / ought to be a more critical part of space combat as without them the ships are effectively blind submarines in a vaccuum.
It does seem like sensors could be / ought to be a more critical part of space combat as without them the ships are effectively blind submarines in a vaccuum.
Well, they might be. MegaTrav gives sensor tasks equal to the number of batteries plus one. Their rationalization is about how long it takes, but then you wonder why the dreadnought can do it 200 times while the fighter built with the same computer and the same number and types of sensors only gets to do it twice in the same time. (It would have actually made more sense if they'd made the number of sensor rolls based on the number of sensor systems installed.)
If on the other hand you think of each battery having its own sensor system to independently target and deduce a target's movement patterns, then it makes more sense why all the weapons are needing to role separately and why only a percentage of those weapons can fire each turn on the larger ships. Also means some of those weapons hits reflect weapons being blinded by sensor damage.
I don't know if it's possible to completely blind a ship though, since sensors like the neutrino sensors and densitometers don't need to be on the surface of a ship to function.
