Some questions for the radar experts over here.
Can anyone provide me with RCS figures of the same object (a/c) for the different frequencies of the radar? Also, as to the probablity of detection for the figures of the radar that various sources quotes. I pulled in this as there was some discussion regarding the same on keyfora .... am putting some quotes from there itself .... hope u guys provide more info on the same ...
The russians give radar detection range with 100 detection probability. That means that target must be detected in 100 % of casas.
The americans on the, other way, say, for instance, that APG-66 radar of F-16A has detection range of 30 miles for 5 m2 RCS, but with 85 % probability of detection.
We can not compare figures for radar ranges in west and russian literature. Simply because they use a different conditions.
In order to stretch radar ranges to the max, west manufacturers use 85 % or even less probability of detection. That means that detection ranges will be much higher.
On the other hand, russians use only 100 % pd for radar ranges. That means, detection range where target must be surely detected in a good weather.
The russian literature say that MiG-29 has about 80 to 100 km max range, and west figures say that F-18A has about 130 to 150 km max. radar range.
So, we have simingly strange statements of German pilots that Mig-29 has, in tests against western fighters, demonstrated much greater radar range that F-18 !!
In fact, this is only because of difference in used Probability of detection in open literature.
The average emitting power and antenna diameter are the best way to find radar range. And Mig-31 will be on top for meny years, especialy with Zaslon M with 360 km range against fighter type targets.
But do you know that RCS depends of radar frequency.
The flat plate of 10 x 10 cm, at right angle to the radar, have RCS of about 1 m2, for the 3cm working frequency.
The same plate, for 10 cm frequency, have RCS of about 1250 m2.
For frequency of 3 cm, RCS of F-4 or F-15 is 5 m2, for a dove is 0,01.
The RCS of 0,0001 which you mentioned, can not be calculated by that way.
We do not know how much radar return could be get from metal sphere of 12 mm diameter. It has to be measured. The RCS is not cross section area.
some replies for the above 'theory' abt the probablity of detection were these --
Harry, there is no such thing as a 100% chance of detection in radar. Radar manufacturers often quote "typical" ranges which are generally average not peak values, and the MiG-29 manual gives all radar range figures as upper and lower limits. Detection range will be usually somewhere between the two. Even then, in certain circumstances, the target may be detected closer or further away than quoted.
Is funny that you contine with this BS about radars with 100% "detection probabiity", man, give us a break please!...
but what i got to see was the below post made by the above poster, quoting some ex-phantom flyers. In his own words, "Some interesting details I found from ex-US Phantom flyers" ---
One source gives 153kW as PPeak for the APQ-100, 0.4-2.0 uS pulses, PRF
1060, 500 or 330, 3 x 3 deg. beam (F-4C). From the same source, the APG-59 is
credited with 1 kw, but that's Pavg, with a 44% duty cycle. Avg.
detection range on a 5m.^2 target is 60nm. I don't know if that's for a
50%, 90% or other % probability of detection (F-4J).
so hopefully waiting to hear more on these figures, mainly -
- RCS figures for different fighters for the different operating frequcney of different radars
- the case with our own Bars radar, but i guess, it must be for the lowest working frequcncy (3cm?) @ 100% pd.
Also, whats are the ranges for the highest operating frequency against different targets and if at all a target with 0.0001 sqm rcs really exists?
One thing i must note here is that, when mentioning abt the Flanker threat, i've seen many talk abt the Russian approach of fighting against lower RCS fighters (mostly the Raptor). It being that, their approach was to burn through the 'stealth advantage' with poweful radars ands track them, where as the Raptors game wud be to remain silent with the wingman sneaking-in to kill the Flanker who is focusing on his prey (in the case of an enviornment where AWACS is not available).
So cud the the 'burning through' mean, the full power emitting at the highest working frequency to detect the very low rcs fighters?
hope u guys will help me out .... tks in advance.