Since I am weighing in late on this I will just keep my comments to a summary rather than responding to the upthread posts:
1. I keep finding the fact that I need to turn on active sensors to find out even “Who” is out there a little disturbing. EM and Thermal signatures should be different enough to at least get the racial profile.
I know that in the real world you can learn a huge amount from passive sensors. In Aurora you can tell the race of a population from their emissions so I guess it wouldn't be too much of a leap to identify the specific race from their engine emissions, or their active sensor emissions. However, on the other hand I do like the uncertainty that this brings to the game and the fact that you never really know what that thermal/EM contact is unless you use active sensors. It also avoids a potential programming can of worms where players may want to simulate the engine or sensor emissions of other races. So in Aurora, much of what you would get from real world passive sensors is actually part of what you get from Aurora active sensors.
2. I would agree that if active sensors can provide information it would have to be FC. A search radar simply does not generally have the resolution to really give you any information other than “object, X big”.
I think there is general consensus that if tech scanning remains, it will be from fire controls rather than active sensors.
3. The idea of getting some passive targeting will be nice.
I will add this at some point, although as I mentioned the identity of the target will remain unknown without actives.
4. Knowing a FC system has locked on should be detectable by at least the Task Group. If an Owl Screech lights somebody up you normally get enough scatter/leakage to know it. Admittedly Aurora ships are further apart, but they systems should be that much more sensitive too.
I think for simplicity my preference is for fire control to be generally detectable, although I might make it a simple flag for active fire control on a unit, rather than showing the range.
I will admit that my service experience and historical/fiction readings have always made me a large proponent of operating under a strict EMCON guideline and picketing systems ala Weber’s “Bugs”. I can remember many times that if we did not have a bird up we were ID’g the opposing forces purely off of their emissions. Radar might have a contact but if you wanted to know what it was then you would rely on the EW to tell you it had a Surface X, Conical Scan Y, and Raster Z. Correspondingly that would get you down to 1 or 2 classes of ship and you could then use intel to pin down the exact ship. As a matter of fact many radar emission signatures vary enough ship to ship that you can literally tell “Hull X” from pure passives if you have the base intel.
The fact that Aurora makes me go active to get any decent data has made it so that I have considered a throwaway penetration ship so that I can make the detection and then blow the ship up (if needed) so that I can conceal true bearing to fleets or WPs. Unfortunately I have not had enough time to get deep in a game to possibly need it.
As I mentioned above, I accept that in reality passives can give you a lot more information that in Aurora. Its really a game design choice rather than a misapprehension on my part regarding passives vs actives.
Steve