The F-22 deosn't appear as a "small bird" to a radar at 200,000 metres, thereby fooling the enemy into thinking they are looking at a small bird.

 

VLO allows you to AVOID being spotted until you're about 15,000 metres away...but hopefully the F-22 has released it's weapon at 40,000 metres and it arrives LONG before your opponent sees the F-22. 

 

As I said any help at all, or any insight/constructive criticisms highlighting potential flaws/feasible parts of my theory would be much appreciated.

Thanks everyone

 

That is the countermeasures half of VLO.

 

You can't be sure its a Mach 2 sparrow  if every sparrow out there shows up as a Mach 2 sparrow, all 2000 of them, on your futzed up radar

 

If you make it impossible to extract a doppler component either through signal processing or interferometry then you cannot velocity discriminate. 

 

H.

 

 

H.

 

Too many :) unfort the prevailing view amongst the jackasses is a failure to recognise that any VLO asset does its job as part of subset of a planning event that involves other ewarfare assets, track managers, flight buddys, and a raft of other system participants..

this lone ranger concept still remains popular though.....

Probably the most valuable thing I've learned in my time here, that it's about the systems.  

 

Seriously, Herald, this is why I do, repeat do believe that you are an independent contractor/consultant.  I realize I only have the potentially unrepresentative sample of many hundreds of StrategyPage posts to judge by, but I figure you can not possibly make your living in a position where you have to actually explain not just "what" to people who already understand the material, but also the "how" and "why" to people who do not.  Just re-read his question and assess the level of knowledge implicit in the content of his question and theory, including his very revealing self-assessment, and now figure the odds of how many words he understood from your reply.  :-)

 

To JTR, I also am not an expert, but I believe I am not butchering the subject too much to suggest that you start going wrong from where you seem to assume that all radars can detect small birds at all ranges.  For every radar there is a lower limit to its ability to detect a target based on the strength of the processed returned signal, meaning that as the signal gets weaker, it reaches a point where the target can no longer be reliably detected.  One factor that affects this signal strength is distance from the emitter to the target (and then to the receiver, which for nearly all radars is the same distance).  Another factor is the Radar Cross Section (RCS) of the target, which depends on several variables (that I think are actually functions of each other, i.e., interdependent) including frequency of the signal, shaping of the target, and the degree to which the materials of the target scatter the reflected radar energy in directions other than back toward the radar receiver (I'm trying to refer to stuff like "Radar Abosrbant Materials" and not just repeating my second item, "shaping of the target").

 

If everything else about two targets is equal, then for any given radar that radar will detect the target with the larger RCS (with respect to that radar) further away from it than it will detect the target with the smaller RCS (with respect to that radar).  As another poster pointed out, the practical effect of LO is that for any given radar the LO aircraft can get closer to that radar before being detected than can the non-LO aircraft.  A further effect of LO is that actually LO potentially *CAN* make the LO aircraft actually "invisible" to some radars in some cases.  This can occur when the LO aircraft presents such a low RCS to that radar that the radar in actual use can *never* receive a return signal that is strong enough to be reliably detected.

 

So you mean to say that the USAF uses ECM?  How many jackasses on how many boards have I seen post that the USAF doesn't have much in the way of ECM since they spent all the $ on stealth?

US air tactics emphasize ECM.

 

Its just that its not talked about, with good reason.

H.

What am I supposed to do? Start with aluminum foil dipole decoy reflectors cut to 1/2 length of a radars primary propagation frequency in WW II (window) that was used to clutter German radars and assume that the man is a democrat in Congress?

 

Look, today, even low observable as fine as that is, can be defeated close in (fairly simply) by a strong radio beam that generates a return signal that can be processed, or by a clever defender who teases route, time and altitude patterns out of an attacker who does not physically vary his attack patterns .

 

So I cut to the heart of offensive countermeasures which is that you generate noise, decoy measures and false signal return based in several simple never changing physical principles so that you cam defeat the radars, optical, and heat sensors-i.e. futz the signal receiver/processor.

 

Those are signal noise, distance, reflection, refraction, opacity and the transparency indexes.    

 

-that a velocity component has to be signal time-matched through a filter, de-filtered and decompressed so you can measure frequency shift ratios and extract the speed component. That holds true for Willey Mays as well as for any French, Chinese, or Russian radar, all of which we foug

 

The premise of the question is a little bit flawed. 

 

Radars can't "see" every object of every size out to a uniform distance.  Radars detect targets by emitting RF energy and detecting the energy reflected back from the target.  As the RF travels to the target, it attenuates due to scattering and atmospheric effects, causing it to weaken in proportion to the square of the distance to the target. The weakened signal must then be reflected by the target; the smaller the target's RCS, the less signal reflected.   The reflected signal then travels back to the emitter, again weakening in proportion to the square of the distance.  And the radar must receive a certain minimum amount of reflected energy back from the target in order to distinguish a target from background electromagnetic noise.

 

All of which is to say that the smaller a target's RCS, the shorter the distance at which a radar can see it at all.  Depending on the power level of the radar, it might detect a building-sized target at hundreds of miles, a typical fighter-sized target at one hundred miles, and a sparrow-sized target at tens of miles.  So the notion that you can just look for every sparrow-sized object within 200 miles, and just pick out the ones moving faster than 100 mph, is not valid.

 

Of course, this does mean that at some distance, even a VLO fighter can be detected by a radar; the distance is determined by the radar's power level, frequency, and aperture size, not to mention ECM as others have stated.  But, because of the propagation loss I described above, the target can detect the radar at a distance many times greater than the radar can detect the target.  VLO aircraft can use this to their advantage, for example by maneuvering so as to remain outside of the field of view of the radar (if it is a fighter radar) or to maintain a certain distance from the radar (if it is an AWACS or a ground based search radar).

 

Anyway the upshot is that this whole notion of "RCS the size of a sparrow" or "size of a marble" that gets tossed around in the media is really misleading.  It doesn't work that way, and detecting VLO aircraft is not a trivial problem to solve.