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#1
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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. |
#2
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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. |
#3
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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. |
#4
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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 |
#5
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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) |
#6
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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. |
#7
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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. |
#8
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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. |
#9
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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. |
#10
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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 |
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