Detecting stealth?

MIG-31 radar…
The 1.1m diameter phased array antenna weighs 300kg, the whole radar weighing in at 1000kg. Zaslon uses an Argon-15A computer (first airborne digital computer designed in USSR). Zaslon operates in 9-9.5 GHz band. It detects and engages targets down to 25m, including cruise missiles. Maximum possible search range is 300km for a large airborne target.
Range, headon, versus bomber: 180-200km search, 120-150km track
Range, tailchase, versus bomber: 90km search, 70km track
Range, headon, versus fighter : 120km search, 90km track
Zaslon can detect targets as small as 0.3 sq. m radar cross-section (RCS) to a maximum range of 45 km

www.overscan.co.uk...

According to the following site F-22 RCS can be 0.0065m^2 so thats 20-25km range...

www.aerospaceweb.org...

or is there a minimum resolution possible?

On the russian radar site there are a number of old IRST systems used on M-23M that could detect supersonic bombers at 85km and subsonic bombers at ~60km. A stealth plane has some ir signature reduction but its not going to do much. Maybe reduce these figures by 1/2 ?

I wonder what modern IRST system could do?

You are never goping to get an accurate answer to your questions because:

1) the most classified aspect of a stealth platform is it's RCS at x-band

2) the most classified aspect of an x-band AESA is it's detection and tracting capability against a VLO target

Why don't you just write a letter to DIA and ask for the data, I'm sure they would oblige you....

[Quote] Why don't you just write a letter to DIA and ask for the data, I'm sure they would oblige you....[/Quote]

Why would I waste my time asking them? The math is availible and can be crunched down.NOthing is that secret that it can't be figured out.

I herd a rumour that old WW2 tube radar could detect stealths.

There are other ways to detect low observable aircraft.

Look for turbulent wake in the air behind the aircraft. Even if your doppler radar cannot pick up the aircraft itself, you may be able to detect the wake. Wingtip vortices are a dead giveaway.