yes i was mistaken, i thought pirate also had a laser range finder. my bad
ok, they get range etc normally from a radar/sar overlay ?
wvr the pirate as i said possibly by its self but i think it will be better with using with hms as a combination
for full bvr, i need to read up on it, its a big task with lots of variables did they give any indication what range is feasable
how is the pirate hooked into navigation to give a decent bearing to triangulate with other platforms or does that need help with radar
i’m unsure how the tracking works
you dont have to answer the questions, its more what i need to find out
i dont mind getting my butt kicked and shown where im wrong
No problemo. Everyone gets is own “butt kicked” sometimes, is part of learning. I had my own posterior handed to me on a plate an awful lot of times on an awful lot of internet foruns.
Range – The basic process of getting range from a target that was detected by a passive sensor, is indeed cuing that big mechanical dish that is inside the frontal “pointy thing” AKA “radar”. If using the radar is not possible/desirable there are alternatives. In the DTI article that i´ve mentioned (and bloodshot linked, thanks), Bill Sweetman mentions two techniques that can be used by a “Pirate” operator, triangulation and dinamic ranging.
Not being an expert on IR sensors (far from it) i can only speculate, but is probably safe to assume that is used the good old trigonometry that our math teachers hammered at our heads in school.
Triangulation – We have three points in space, the positions of two (A and B) are perfectly known, the third (C) is detected by A and B using a passive sensor, so A and B have a bearing on C.
That means we have a triangle in wich one (in three) of the sides is known (thats the distance between A and B), and two angles in three, so to discover the distance between A and C, and B and C (being C the target), we use the good old sine and cosine laws (exactly like this litle mathematical “game” in here http://www.3eck.org/triangle/en/calculator_simple.php).
We have just discovered the distance between our two “Pirate carriers” (A and B) and the target C!
Using exactly the same equations, and knowing the altitude of A and B, the distances and bearings to C, then the altitude of C is straighforward.
The precision of this technique is dependent on a lot of things, number of detectors (Pirate) being used, the more the merrier, distance, the longer the distance to C the less precise the system gets, etc.
Then we have the shortcomings inerent to IR, i can only imagine that trying to use Pirate in the way described above at low altitude in December, somewhere in Scotland (or any other place in wich rain is constant) is quite a daunting task!
Like some wise old man said “the rain in Spain stays mainly in the plain”, translated it probably means something like “if it rains use a bloody radar”.
Going back to a Typhoon flight, the entire flight works has one single system, the bearings are downloaded using link16, the “C” location is automaticaly calculated and presented to every conected fighter, then is assigned to one or more of them. The AIM-120 is a fire and forget weapon with an active radar, that means that even if the track is not perfect to the meter, we still have a very nice chance of blowing the correct bogey out of the sky. Leave the AIM-120 pointed to the right position and a few hundred meters from “C”, and we have a dead target.
Dinamic ranging – Is a variation of triangulation, instead of having multiple sensors detecting “C”, we have one single sensor reading diferent bearings on a determined time frame, the aircraft flies on a determined flight path (it basicaly jinks left to right, then to left again) that maximises the bearing angles. I can only speculate that this is a lot less precise than using multiple sensors.
Cheers
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