Question about the APG-77

As most of you know, a typical fighter radar can detect a target at ranges
well in excess of where it can maintain a track. Most sources that quote
radar performance fail to make that distinction.

"Guy Alcala" wrote in message
. ..
Scott Ferrin wrote:

In the latest AW&ST it mentions the F-22's radar as having a range of
"over 100 miles" and implies that it's greater than the F-15's. I
recall reading MANY times in the 80's of the Eagle's radar being more
like 150 miles and the Tomcat's nearly 200. I've also read that the
ASG-18 in the YF-12 (which was the one the AWG-9 was based on) was
good for over 300. So what gives? Are they purposly underselling
the APG-77? Is the "over 100 miles" figure against fighter-sized
targets while the high figures of the other radars were against
bomber-sized targets? Inquiring minds want to know.

There was an AvLeak article a year or two ago comparing the then current
planar array radars in the F-16C and F-15C with the AESA variants of
both. All ranges quoted were against 1 sq.m. targets, roughly
representative of a reduced observable fighter (i.e., F-16C/F-18E/F with
RAM, coated canopies, intake mods, etc.) or a non-stealthy cruise
missile, while the standard fighter radar spec. is often based on a
nominal 5 sq. m. fighter target, a fair average for the Vietnam era. The
F-15 has a lot bigger frontal RCS than that, by most accounts. Lots of
corners, and the radar can look right down the intakes and see the fan
blades.

This is from memory so don't treat it as gospel, but IIRC the AESA
version for the F-16C was credited with a range (look-down IIRR) of
between 70-80nm, with the exact figure classified; the standard APG-68
was credited with a range about 1/3rd of that against the same target, or
23.3 - 26.7nm. I don't remember the F-15C w/APG-63(V1) spec, but I think
the AESA requirement was 90nm, and the radar was actually doing somewhat
better, 105nm or so. The F-22 radar spec was quoted as something like
115nm, but was again doing somewhat better, IIRC somewhere in the
125-140nm range. If you're looking head-on at a Buff, 747 or Bear, you
can obviously do a lot better. ISTR there were lookdown detections made
by F-15Cs during DS on 'dirty' (tanks, armament underwing) fighters, of
at least 60nm and maybe 80nm (can't remember, and too lazy to pull out
the magazine with the account). Depending on the aspect and the
particular stores carried, I wouldn't be surprised if the RCS on a
MiG/Sukhoi was up in the 15-20 range if not higher. Unfortunately, the
person on this NG most likely to be able to answer your question with the
real skinny, Harry Andreas, is almost certainly prohibited from doing so.

Guy