Viper Pilot_ A Memoi..

listen to a few seconds of the audio signal from our Threat Warning Receiver
(RWR) and instantly tell what type of enemy radar was trying to bite you. The
good ones knew everything about the enemy systems we thought we’d face one
day. A few could even identify individual radars by their unique sounds, and they
were happy to share the secrets of their art. It was truly amazing to a young officer
like me, and I soaked it in because, until technology caught up, the EWO was the
heart of the Wild Weasel mission.
THE ORIGINAL SA-2, AND ITS FANSONG RADAR, HAD BEEN built to kill bombers and
reconnaissance aircraft. Jammers, countermeasures, and threat-warning equipment
had leveled the playing field somewhat, but the most expedient countertactic was
low-altitude flying.
You see, radars all have a gap, a blind spot in coverage, called a “notch.”
FANSONG’s blind spot was its inability to separate the radar return of the target
from the much larger return generated by Earth. If you flew low enough, you could
hide in the ground “clutter,” and the radar would never see you—like wearing a
black T-shirt to hide in the dark. If the radar can’t see you, then it can’t track and
kill you. And if it had already launched and exposed its position, you could defeat
the system by dropping down and flying very low. This kind of flight is impractical
for most big aircraft, but it’s ideal for fighters.
Einstein, ever the father of tactics, correctly stated that every action has an
opposite reaction. Everyone started going low after Vietnam, so, to counter the
low-altitude threat, Soviet and American engineers developed systems that had no
real clutter notch, because they tracked an aircraft’s velocity. These missiles could
also be launched visually using TV cameras, since a fighter at low altitude was
easier to see than one at 20,000 feet.
The new radars were designed to be faster and more accurate, because they had
to acquire, track, and launch in seconds rather than minutes. They were also
mobile. Big, fixed SAM sites like the SA-2 were easy to see and therefore simple to
avoid unless they were deployed around high-value targets we needed to destroy.
The Soviets were aware of this, so they’d developed a particularly nasty family of
mobile SAMs and greatly improved anti-aircraft guns. These systems filled in the
gaps in distance and altitude coverage and were deployed around the larger
strategic sites for overlapping coverage. They were highly mobile and attached to
ground forces for air defense. This meant there were lots of them, and they could
be anywhere.