Question about the APG-77

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.

Scott Ferrin wrote in message
...


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.

I'd like to know as well. The F-15s in question were supposed to be equipped
with AESA antennas using the same T/R modules used in the F-22's antenna.
The aperatures are about the same size and the back end processing
algorithms are likely the same generation so I'd expect about equal
detection range.

I seem to remember from my A.T. days in the navy that the 200 miles range of
the AWG-9 was against a bomber size target


Scott Ferrin wrote in message
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.

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

After an exhausting session with Victoria's Secret Police, Guy Alcala
confessed the following:

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.

Just to add to that...also from memory...in the F-16A, 15+ years ago I
recall the gouge for radar contacts of F-15s/F-4s at a nominal 32nm,
an F-18 just inside 30nm, and an F-16 at 26nm.

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).

A buddy that flew Mudhens in DS told me a funny story. After the
fighting stopped they were in a 2-ship CAP NE of Baghdad near the Iran
border. AWACS vectored them W on a contact coming out of Syria (or
Jordan). The Mudhens went "buster" toward the contact at 180 degrees
aspect in a race to get the contact before a 4-ship of F-16As (that
were pimping AWACS to give them the trade). AWACS informed the Mudhens
they had about minute before the Vipers would get the intercept unless
the MHs could take a "judy." My bud had his WSO put the range scale to
their Max (180nm or 200nm sticks in my noggin) and the radar cursors
at the top. The WSO locked up the contact at Max range and they took a
"judy," but the Vipers were actually closer. He wound up doing a
high-low conversion with a 15k' altitude differential on an unbriefed
IL-76 sporting the Red Crescent inbound to Bullseye.

Speaking of trade...Guy got anything to trade me for Ritchie's two
Corona Harvest interviews (if you don't have them)...or other SEA
"stuff" I might have to interest you.

Robey (use yebor[at]comcast.net)

On Sun, 30 May 2004 23:43:31 GMT, Robey Price
wrote:

After an exhausting session with Victoria's Secret Police, Guy Alcala
confessed the following:

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.

Just to add to that...also from memory...in the F-16A, 15+ years ago I
recall the gouge for radar contacts of F-15s/F-4s at a nominal 32nm,
an F-18 just inside 30nm, and an F-16 at 26nm.

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).

A buddy that flew Mudhens in DS told me a funny story. After the
fighting stopped they were in a 2-ship CAP NE of Baghdad near the Iran
border. AWACS vectored them W on a contact coming out of Syria (or
Jordan). The Mudhens went "buster" toward the contact at 180 degrees
aspect in a race to get the contact before a 4-ship of F-16As (that
were pimping AWACS to give them the trade). AWACS informed the Mudhens
they had about minute before the Vipers would get the intercept unless
the MHs could take a "judy." My bud had his WSO put the range scale to
their Max (180nm or 200nm sticks in my noggin)

I'll bet those are the buttons I recall seeing in the cockpit of a
F-14A. The highest one was 200. Interestingly enough in Aerospace
Projects Review there is a photo of the mockup of the XF-103 and it
has a similar set of buttons the highest of which is 200 miles.

On Sun, 30 May 2004 17:21:01 -0400, "Paul F Austin"
wrote:


Scott Ferrin wrote in message
.. .


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.

I'd like to know as well. The F-15s in question were supposed to be equipped
with AESA antennas using the same T/R modules used in the F-22's antenna.
The aperatures are about the same size and the back end processing
algorithms are likely the same generation so I'd expect about equal
detection range.

Are you sure about that? ISTR the nose of the F-22 being quite a bit
shorter top-to-bottom than the Eagle's. I know the bulkhead the
APG-77 is mounted on is tilted back a bit but not that much. Is the
number of modules on the two the same? Also the F-22 went to liquid
cooling of the avionics presumably because they draw a lot more power.
I remember reading that the APG-77 is unusually powerful.

Scott Ferrin wrote in message . ..
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.

My guess is it's talking about cruise missiles, since that article's
context was primarily about cruise missile intercept-and-kill
missions. I talked to David Fulghum (author of the article and a
neighbor of mine) the day after I read the article online and he said
that there were more details to be gotten that he wasn't able to dig
out in the time he had, but he was talking about the cruise missile
mission to me then, too.

Scott Ferrin wrote in message
...
On Sun, 30 May 2004 17:21:01 -0400, "Paul F Austin"
wrote:


Scott Ferrin wrote in message
.. .


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.

I'd like to know as well. The F-15s in question were supposed to be
equipped
with AESA antennas using the same T/R modules used in the F-22's antenna.
The aperatures are about the same size and the back end processing
algorithms are likely the same generation so I'd expect about equal
detection range.

Are you sure about that? ISTR the nose of the F-22 being quite a bit
shorter top-to-bottom than the Eagle's. I know the bulkhead the
APG-77 is mounted on is tilted back a bit but not that much. Is the
number of modules on the two the same? Also the F-22 went to liquid
cooling of the avionics presumably because they draw a lot more power.
I remember reading that the APG-77 is unusually powerful.

That's what I mean. The F-22 nose is certainly not larger than the F-15
radome (42 inches IRRC). The F-15C AESA aperature may be sparsely populated
with T/R modules which would account for the difference in performance. T/R
modules are still on the cost-volume ski slope, still pretty expensive.

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