Sensor Coverage of a large GG ?
- Thread starter Matt123
- Start date
Essential? 3 equitorial. 1LS = 300,000km (in traveller. In real life, a few thousand less.) So, put them out at 150,000, and you have covered the giant itself; with all approaches having 2-3 sats covering.
At 6LS (1,800,000km), 6 more, plus another 6 in polar orbit at about 1,750,000, to insure polar coverage, and this gives pretty decent coverage out to 12LS.
To cover the 100 diameter range? 90 million km? thousands, many. Pi*D
180*3.14/3.6 - 158 just equitorially...
lol, I didn't expect the answer to be so resource low... It does however bring our trusty raider much closer to the GG. But I'm not sure that changes our previous intercept calc by much. (ok Bill, I should have asked this first...)
So hypothetically, a raider could drop off its ships boat on one side of the GG & then sit on the other. The two sensor points giving sensor coverage of all approaches to the GG. out to say 3 LS (ships boat sensor limit) 900,000 km on either side with overlapping coverage in the middle out to only (guessing) 700,000 km.
A 4g raider can cover the 150,00 km to the GG in about an hour, arriving at 0g. I'm picking that still gets him there before the merchant and lets him intercept on average 1-2 hours before the merchant reaches the GG.
Sounds plausible?
So hypothetically, a raider could drop off its ships boat on one side of the GG & then sit on the other. The two sensor points giving sensor coverage of all approaches to the GG. out to say 3 LS (ships boat sensor limit) 900,000 km on either side with overlapping coverage in the middle out to only (guessing) 700,000 km.
A 4g raider can cover the 150,00 km to the GG in about an hour, arriving at 0g. I'm picking that still gets him there before the merchant and lets him intercept on average 1-2 hours before the merchant reaches the GG.
Sounds plausible?
B2 military detection range is 2ls, not 6ls... with 3ls being the limit of tracking range after detection.
[Arguments as to the realism of this are epic, but I am only reporting the rule as written.]
Near something like a GG, though, which might be spewing out noise all up and down the EM spectrum, the LBB2 rule reducing detection range for doggo vessels (or those executing Dishkili Maneuvers) to 1/8th normal might be appropriate -- thus 1/4th of 1ls military (and 1/16th of 1ls civvie).
Arse. Ta for pointing that out.
Also interesting. I generally dable in HG, poor excuse tho' for not reading that section properly.
Military sensor range 2LS (600,000 km)
All others 0.5LS (150,000 km)
If the trader is running silent to the GG, and one would assume a prudent Captain would, the ranges are halved. Our Raider has an effective range of 1LS or 300,000 km, whilst the merchant (assuming a silent chasing raider) sensor range is 75,000 km.
Using Aramis figures, we can still cover the majority of the GG with two pickets (I'm now assuming the ships boat has been fitted with military grade sensors). With both ships in orbit around the GG, I'll pick an average detection range of (0-300,000 km) 150,000.
Which leads to the same conclusion as my last post, the raider intercepts the merchant an hour or two before it reaches the GG.
You could presume fewer detectors if you turn satellite sensing into a skill check.
Setpoint: X LS is 2+ on 2D; i.e. automatic. Tracking is 150% of that.
Double the distance, halve the probability.
2X LS is 7+ on 2D.
4X LS is 9+.
8X LS is 10+.
16X LS is 11+.
32X LS is 12+.
Assume the unit of time is a space combat round.
Scale your initial range to suit your needs. 2 LS military typical, less near a GG or star, or whatever your needs are.
Anyway, now you can employ even fewer detection satellites at the 100D point.
Setpoint: X LS is 2+ on 2D; i.e. automatic. Tracking is 150% of that.
Double the distance, halve the probability.
2X LS is 7+ on 2D.
4X LS is 9+.
8X LS is 10+.
16X LS is 11+.
32X LS is 12+.
Assume the unit of time is a space combat round.
Scale your initial range to suit your needs. 2 LS military typical, less near a GG or star, or whatever your needs are.
Anyway, now you can employ even fewer detection satellites at the 100D point.
Using modern RADAR as a guide, running silent would include not actively scanning. That would seem to be a tradeoff between reducing your chance of being detected while increasing your chance of being suprised (on the one hand), and increasing your chance of being detected but spotting the hunter in time to flee (on the other hand).
A shot in the engine room is a tough 'first hint' that somebody is out there. A prudent captain could go either way.
Or... the raider could play SDB and lie doggo within the GG atmo, track the merchant once the merchant begins a skimming run (it should be easy to detect at that point), then strike once the target is accelerating away from the GG post-refueling...
True...
The raider hiding in the GG may not be as effective as it can't watch the approaches. If its hiding, no-one can see in & they can't see out. At best he can perhaps watch a very narrow arc of space, restricted by the bulk of the GG behind & the density of the GG atmosphere to left & right. But otherwise he's essentially relying on the merchant randomly arriving on his doorstep. Thinking about, even SDB's could do with pickets.
It occors to me the raider has to expect the possibility of a trap, with the trader as the bait, followed by a 6g Destroyer 1LS (300,000 km) running silent. Inside the 10d limit, in a poetic role reversal, the raider has few choices but to fight & run.
It might be a cheaper & more effective use of large escorts (vs the cheap escorts I'm working on elsewhere) than trying to catch a raider by randomly searching GG's. Just tag along behind some poor schmuck (PC's...) or unescorted convoy & see if anything tries to bite them.
Hmmm, its got me wondering now about ships making a run for the GG & hiding in the atmosphere. How many 20 min turns would an large escort get on a raider before the raider got to cover? Means we've got to get more precise on the raiders intercept of the merchant to figure out the starting points for the escort vs raider. Anybody want to help out? I'll post parameters in a minute.
(I've thought about the merchant hiding, but strategically, the merchant getting a fright achieves most of the goals of commerce raiding. If the merchant survives the 4-6 rounds before hiding, well, good on him!)
Indeed, but passive sensor emplacements -- on the surface of face-locked GG moons or strewn about any rings present, for example -- can indeed watch those approaches, then those sensors can be polled at intervals or else transmit only any interesting observations, and bingo: the raider moves to intercept/pursue. It is, after all, one of the ways SDBs do it.
Wilderness refueling is fraught with peril, and it should be. Perhaps merchants should launch small craft to fly cover during refueling ops -- I am sure we can come up with a catchy name for such a practice...
