How long until current 'stealth' techniques are compromised?

In message , robert
arndt writes
(Denyav) wrote in message
...
It seems alot of importance is put into stealth for aircraft these days,
just wondering who is working on a countering radar system for it?

Germany has its own version of the '90s Czech anti-stealth radar
(which they purchased)as well as EADs developing an anti-stealth
missile that uses multiple seekers to hunt stealth aircraft. One of
the seekers is a plume detector which goes back to WW2 and the
Feuerball weapon (aka Foo Fighter).

Would you mind expanding on your comments on 'Feuerball' and 'Foo
Fighters', Robert?

Mike