Airborne Passive Location

[bsq]

The routine for generating a location based upon passive data from an aeroplane is not correct - may be this is a limtation of the game engine or may be it is a problem with 'naval thinking'.

If a SLQ32 or UAT picks up a radar emission it will give a lob and and a location based upon the power level it receives so the stronger the signal, the closer the system thinks the emitter is. When it sees it again say 30 seconds or even a minute later, it can still only say well its over there and I think its that far.

When an airborne ESM or ELINT system picks up a contact, the first LOB is just that (its a case of its over there somewhere between me and the horizon). 30 seconds to a minute later the aeroplane is now several miles from where it was. The second LOB gets compared to the first and there is a cross cut. As time goes on (only a few to several minutes) the location gets refined down to a matter of a few miles or less.

So whilst for ships, a constant changing (increasing or decreasing) area of probability (CEP) is OK, for aeroplanes this is wrong, the CEP should always decrease to the point where (if you are firing HARMS) you have a point to aim at.

Of course if the sensor model does not/cannot support this then ok, but if it can be done, it should be done. It will mean that these (expensive) passive assets actually have a part to play in the game...

[navwarcol]

I have been looking at this for the scenario I am making as well. Usually using passive airborne assets can give a fairly reliable fix as you wrote, within a few minutes, and definitely could within the course of an entire mission spent looking (passively) for them, say flying parallel with a coastline, etc, at least for targets that are immobile such as radar/SAM sites, etc.

[Blu3wolf]

for non moving targets, this is correct.

as soon as the emitter is moving, things get complicated.

[bsq]

You'll still get a cross cut because the aeroplane is moving so much faster, just wont be as accurate.

[Blu3wolf]

it does get confusing though, because the cross cut is trying to eliminate areas that the emitter cannot be, based on past emissions.

if the emitter is moving - say at 400 knots - then the past emissions have no bearing on its current location, completely invalidating that technique.

if the emitter is moving at 16 knots, on the other hand, then past emissions will still have a bearing on its current location, provided the ELINT aircraft is moving much faster than 16 knots - probably a safe assumption.

[bsq]

Which is why I asked only if the sensor model could support it [:)]