AN/APG-77 detection range

Unread postPosted: 29 Mar 2016, 21:12
by ferry265
Hello. I did read sometimes that Raptor´s radar AN/APG-77 can detect 1m2 on 400km away. Is that true ?
Thanks for answer. :wink:

Re: AN/APG-77 detection range

Unread postPosted: 29 Mar 2016, 21:54
by str
Sure, in search or look-down modes. But there's also the look-through mode, which peers through the center of the earth to tell you what's flying around on the opposite side of the planet.

/s

Re: AN/APG-77 detection range

Unread postPosted: 30 Mar 2016, 12:34
by mixelflick
ferry265 wrote:Hello. I did read sometimes that Raptor´s radar AN/APG-77 can detect 1m2 on 400km away. Is that true ?
Thanks for answer. :wink:


Make that 407km away.

Revised and updated DOD specs, for PAK FA program management to shoot for...

Re: AN/APG-77 detection range

Unread postPosted: 30 Mar 2016, 14:10
by ferry265
Thank you very much to both :wink:
And can F-22 detect enemy stealth jets on longer distance with AN/ALR-94 ? Teach me :D
Thanks!

Re: AN/APG-77 detection range

Unread postPosted: 30 Mar 2016, 20:58
by charlielima223
ferry265 wrote:Thank you very much to both :wink:
And can F-22 detect enemy stealth jets on longer distance with AN/ALR-94 ? Teach me :D
Thanks!


First off welcome the board. Also there has been plenty of discussion about topics you are inquiring. You can browse around or use the search function to find your answers. With some you wont get a definitive yes/no.

Re: AN/APG-77 detection range

Unread postPosted: 30 Mar 2016, 21:21
by ferry265
Ok. Thanks for tips

Re: AN/APG-77 detection range

Unread postPosted: 30 Mar 2016, 22:45
by eloise
ferry265 wrote:Thank you very much to both :wink:
And can F-22 detect enemy stealth jets on longer distance with AN/ALR-94 ? Teach me :D
Thanks!

Have a look at garry blog
viewtopic.php?f=22&t=29022

Re: AN/APG-77 detection range

Unread postPosted: 07 Aug 2016, 10:22
by popcorn
Re APG 77 and APG 81 is there any technical reason why you couldn't have a mix of T/R modules to provide a multi-band radar capability ie. not be limited exclusively to X-band. If possible, this could make it a more versatile jamming patform.

Re: AN/APG-77 detection range

Unread postPosted: 07 Aug 2016, 18:18
by SpudmanWP
AESA radar modules have to be physically nest to one another in order to be able to steer, There is also a set number of modules needed in order to steer to the to the extremes of the sides.

Given this, you can't simply add a few along the edge. You would need large blocks of each.

The holy grail of AESA radars would be to make the module itself multiband.

Re: AN/APG-77 detection range

Unread postPosted: 07 Aug 2016, 23:44
by popcorn
So if I understand it right, they could block off a portion of the array and populate it with T/R modules of a difcerent frequency. Short of achieving the holy grail of a multi-band T/R module, perhaps this could be an acceptable compromise? All speculative...

Re: AN/APG-77 detection range

Unread postPosted: 08 Aug 2016, 03:53
by SpudmanWP
While you would get multiple freqs, you would also have a lower range with each freq.

For the best range, you need them all transmitting at the same freq.

Re: AN/APG-77 detection range

Unread postPosted: 08 Aug 2016, 04:33
by popcorn
SpudmanWP wrote:While you would get multiple freqs, you would also have a lower range with each freq.

For the best range, you need them all transmitting at the same freq.


I agree. I was thinking there might be a sweet spot where they could achieve an acceptable level of performance in X-Band using a reduced number of T/Rs while having the balance in T/Rs of a different frequency. Give up a bit on max range but gain in oher areas eg. being able to jam in more frequencies.

Re: AN/APG-77 detection range

Unread postPosted: 08 Aug 2016, 07:04
by hornetfinn
As with all the good ideas these days, somebody has thought about it long time ago. There are ways to do what you describe and there are patents which describe how it can be done.

Some patents:
https://www.google.com/patents/US6891514
https://www.google.com/patents/US6239762
http://www.google.ca/patents/US7830301

Basically, you can stack antenna arrays together and each would work in different frequency. As antenna arrays get thinner and lighter (especially with future GaN technology), it might be very possible to stack antenna arrays in such a way that the whole radar/jammer/EW/comms system covers say UHF band to Ka band or something similar. I'd say we can stop talking about radars (Radio Detection and Ranging) system and make up a new name like "RF system" as these systems are now having capabilities way beyond radar functionality. Another way is what SpudmanWP described, having wideband modules. That has the advantage of having lower volume and weight and simpler design and construction (and thus costs). Having one array with different sized modules would not work very well as that would affect performance in each frequency. IMO, in the future we will see combination of both stacked arrays and multiband modules. Very likely 6th gen fighters in the future will have some insane RF capabilities that take F-35 RF systems to totally another level.

There are definitely a lot of difficult challenges trying to combine different frequencies to one system and this is probably why complete AN/SPY-3 system has two different and separate antenna arrays for X-band and S-band operations. NGJ also seems to have two separate arrays for different bands.

Re: AN/APG-77 detection range

Unread postPosted: 08 Aug 2016, 10:46
by popcorn
Thanks hornetfinn, sounds rrasonable.

Re: AN/APG-77 detection range

Unread postPosted: 20 Apr 2017, 22:43
by kapcapkap
mixelflick wrote:
ferry265 wrote:Hello. I did read sometimes that Raptor´s radar AN/APG-77 can detect 1m2 on 400km away. Is that true ?
Thanks for answer. :wink:


Make that 407km away.

Revised and updated DOD specs, for PAK FA program management to shoot for...


Can you please provide a link, or other means of finding this source, for this information; it would be a very useful source to cite. Thank you.

Re: AN/APG-77 detection range

Unread postPosted: 02 May 2017, 01:54
by nutshell
Do you guys remember the video of Skunkworks and their nanotubes skin?

I think, as futuristic as it sounds, the plan is to transform the whole skin of a frame into a single massive antenna.

However i don't really have no clues on how a nanometric T/R module would perform nor if its possible to change the frequency at those modules would eventually works.

Yet i think the 6th gen will be a lot about exploiting every single inch of surface at disposal.

After all, the radar tech itself is constrained mostly by space (rather then weight).

Re: AN/APG-77 detection range

Unread postPosted: 02 May 2017, 12:44
by botsing
nutshell wrote:After all, the radar tech itself is constrained mostly by space (rather then weight).

I assume that the radar is also constrained by the amount of energy it can use, the amount of energy that the airplane can give it and the capability to dissipate any excess heat.

Re: AN/APG-77 detection range

Unread postPosted: 02 May 2017, 18:43
by nutshell
Dunno if energy absorption might be a real problem; after all you have the equivalent of 2 petrol powerplants generating energy.

Heat is an issue tho.

Re: AN/APG-77 detection range

Unread postPosted: 13 Jul 2017, 22:24
by wewuzkangz
RCS of 1 at 400km oh come on Wiki even states that it is from an unconfirmed sources. Australia airforce net shows a lesser range than that.

Re: AN/APG-77 detection range

Unread postPosted: 13 Jul 2017, 22:48
by wrightwing
APA is not a reliable source of information.

Re: AN/APG-77 detection range

Unread postPosted: 14 Jul 2017, 11:05
by zero-one
wewuzkangz wrote:RCS of 1 at 400km oh come on Wiki even states that it is from an unconfirmed sources. Australia airforce net shows a lesser range than that.


whenever reading APA, you need to be very careful.
he usually uses terms like
"estimated to be", "expected to be", "seems to be", "most likely", "probably".

This means that he has no actual data and is simply doing a wild guess based on his opinion.

I still can't get over how he compares the combat Thrust to weight ratio of the F-35 and Su-30, theyr're actually roughly equal with the F-35A having a slight advantage. But he extends the Su-30's T/W ratio by using AL-37 engines. News flash the AL-37 is just an Experimental derivative for the Su-37 demo plane.

See what he did there?

Re: AN/APG-77 detection range

Unread postPosted: 22 Aug 2017, 01:48
by charlielima223
Perhaps my age is catching up with me and I am hearing and reading things that I want to hear. Perhaps someone here can help me out in some clarification...

A while back I was reading an article about the F-22's capabilities over Syria. We've all heard that its stealth, radar, and passive sensors have been able to provide plenty of intel to other assets. One thing I heard was that the F-22's radar was/is so good that it has been able to identify Russian and Syrian aircraft down to their airframe. I have no experience with radars or being what the Army called "duck hunters", but I wonder if that is indeed true. I am going to make a SWAG that the combination of its passive sensors and radar being so integrated with each other that the F-22 may indeed be able to identify aircraft down to their airframe.

Some one please enlighten me whether this is true or not.

Re: AN/APG-77 detection range

Unread postPosted: 22 Aug 2017, 03:40
by popcorn
Just to clarify, are you asking about the F-22's ability to identify a/c types eg. MiG-29, Su-30,etc. or individual a/c by tail number?

Re: AN/APG-77 detection range

Unread postPosted: 22 Aug 2017, 06:57
by wrightwing
popcorn wrote:Just to clarify, are you asking about the F-22's ability to identify a/c types eg. MiG-29, Su-30,etc. or individual a/c by tail number?

Types, would be my guess.

Re: AN/APG-77 detection range

Unread postPosted: 22 Aug 2017, 07:46
by arian
charlielima223 wrote:Perhaps my age is catching up with me and I am hearing and reading things that I want to hear. Perhaps someone here can help me out in some clarification...

A while back I was reading an article about the F-22's capabilities over Syria. We've all heard that its stealth, radar, and passive sensors have been able to provide plenty of intel to other assets. One thing I heard was that the F-22's radar was/is so good that it has been able to identify Russian and Syrian aircraft down to their airframe. I have no experience with radars or being what the Army called "duck hunters", but I wonder if that is indeed true. I am going to make a SWAG that the combination of its passive sensors and radar being so integrated with each other that the F-22 may indeed be able to identify aircraft down to their airframe.

Some one please enlighten me whether this is true or not.


The ability to identify the type of plane is not new to the F-22. As far as I can tell, F-15 was the first to have that capability used for identifying friend or foe without the need of an IFF interrogator. The radar has some ability to identify the type of plane based on the return from the engine blades, for example. I have no idea how it works, but I'm guessing each engine type produces different signatures which can be matched with known types (kind of like sonar and identifying ships by their engine noise). More modern radars have some ability to create a "picture" of the plane it is viewing and do some matching with known plane shapes (called inverse synthetic aperture radar). However, all of this is probably too dependent on the viewing angle to be 100% reliable, and probably range as well. So if you can't see the engine blades you may not be able to use the first technique. If you're viewing the plane from an odd angle where it's hard to get good reflections from certain identifiable features it may just appear as a blob on ISAR and can't be matched to anything.

But in Syria, if it's being used for that role, it's probably using passive sensors.

Re: AN/APG-77 detection range

Unread postPosted: 23 Aug 2017, 18:44
by charlielima223
Cool beans!

Thanks for the clarification :thumb:

Re: AN/APG-77 detection range

Unread postPosted: 23 Aug 2017, 21:56
by neptune
arian wrote:..... idea how it works, but I'm guessing each engine type produces different signatures which can be matched with known types (kind of like sonar and identifying ships by their engine noise). More modern radars have some ability to create a "picture" of the plane it is viewing and do some matching with known plane shapes (called inverse synthetic aperture radar). However, all of this is probably too dependent on the viewing angle to be 100% reliable, and probably range as well. So if you can't see the engine blades you may not be able to use the first technique. If you're viewing the plane from an odd angle where it's hard to get good reflections from certain identifiable features it may just appear as a blob on ISAR and can't be matched to anything.

But in Syria, if it's being used for that role, it's probably using passive sensors.


...with passive systems info and a library the range and type of weapons could be defined and an avoidance zone plotted to indicate a reference for intercept?
:)

Re: AN/APG-77 detection range

Unread postPosted: 23 Aug 2017, 23:48
by popcorn
oops.

Re: AN/APG-77 detection range

Unread postPosted: 25 Aug 2017, 23:51
by charlielima223
I FOUND THE ARTICLE THAT PROMPTED MY QUESTION!! :D

http://www.military.com/daily-news/2017 ... hting.html

Lt. Col. "Shell," an F-22 pilot and commander of the 27th Squadron

The pilot said the F-22's ability to identify other aircraft -- down to the airframe -- and detect surface-to-air missiles and relay their existence to other friendly forces while remaining a low-observable radar profile makes it critical for the fight.

Re: AN/APG-77 detection range

Unread postPosted: 12 Sep 2017, 12:03
by mas
The Raptor’s radar range is classified, but one pilot said he has “seen targets beyond 320 miles.”

http://www.airspacemag.com/military-avi ... 180957782/

Re: AN/APG-77 detection range

Unread postPosted: 10 Dec 2017, 20:14
by marian159
zero-one wrote:
wewuzkangz wrote:RCS of 1 at 400km oh come on Wiki even states that it is from an unconfirmed sources. Australia airforce net shows a lesser range than that.


whenever reading APA, you need to be very careful.
he usually uses terms like
"estimated to be", "expected to be", "seems to be", "most likely", "probably".

This means that he has no actual data and is simply doing a wild guess based on his opinion.

I still can't get over how he compares the combat Thrust to weight ratio of the F-35 and Su-30, theyr're actually roughly equal with the F-35A having a slight advantage. But he extends the Su-30's T/W ratio by using AL-37 engines. News flash the AL-37 is just an Experimental derivative for the Su-37 demo plane.

See what he did there?

Only wiki shows range 400km against 1m2, if you got something share it, thanks

Re: AN/APG-77 detection range

Unread postPosted: 22 Sep 2018, 16:29
by falcon.16
kapcapkap wrote:
mixelflick wrote:
ferry265 wrote:Hello. I did read sometimes that Raptor´s radar AN/APG-77 can detect 1m2 on 400km away. Is that true ?
Thanks for answer. :wink:


Make that 407km away.

Revised and updated DOD specs, for PAK FA program management to shoot for...


Can you please provide a link, or other means of finding this source, for this information; it would be a very useful source to cite. Thank you.


This was written many years ago, so yes, i think it is very possible.

Image

Source: Aviation Week, Jan. 2007.
https://www.webcitation.org/6Qpsm5PUo?u ... 010807.pdf

Re: AN/APG-77 detection range

Unread postPosted: 24 Sep 2018, 13:58
by mixelflick
That 56 mile/F-15 figure is an old one though, no? These were Eagles used during Desert Storm, and don't take into account the newer AESA radars. Surely, they have the capability of looking beyond 56 miles??

If not, then carrying the AIM-120D is going to be self limiting. It reportedly has a range of 100 miles (or thereabouts), so a radar with roughly half that range is really selling the weapon short. I think I even read once that the new AESA's going into Eagles were MORE powerful than the F-22's AN/APG-77.

Am I off base here, or not understanding correctly?

Re: AN/APG-77 detection range

Unread postPosted: 24 Sep 2018, 15:19
by wrightwing
mixelflick wrote:That 56 mile/F-15 figure is an old one though, no? These were Eagles used during Desert Storm, and don't take into account the newer AESA radars. Surely, they have the capability of looking beyond 56 miles??

If not, then carrying the AIM-120D is going to be self limiting. It reportedly has a range of 100 miles (or thereabouts), so a radar with roughly half that range is really selling the weapon short. I think I even read once that the new AESA's going into Eagles were MORE powerful than the F-22's AN/APG-77.

Am I off base here, or not understanding correctly?

That's the MSA radar, not the AESA radar. It's also for 1m^2 targets.

Re: AN/APG-77 detection range

Unread postPosted: 25 Sep 2018, 14:32
by swiss
wrightwing wrote:
mixelflick wrote:That 56 mile/F-15 figure is an old one though, no? These were Eagles used during Desert Storm, and don't take into account the newer AESA radars. Surely, they have the capability of looking beyond 56 miles??

If not, then carrying the AIM-120D is going to be self limiting. It reportedly has a range of 100 miles (or thereabouts), so a radar with roughly half that range is really selling the weapon short. I think I even read once that the new AESA's going into Eagles were MORE powerful than the F-22's AN/APG-77.

Am I off base here, or not understanding correctly?

That's the MSA radar, not the AESA radar. It's also for 1m^2 targets.


But even for the APG-70, this performance is bad. The small RDI Radar from Mirage 2000 in the 80s comes close to that Range.

According to this document the APG-70 has a range of 185 km against a Air target. I assume 3-5 m2.

https://www.forecastinternational.com/a ... _RECNO=729

Re: AN/APG-77 detection range

Unread postPosted: 28 Sep 2018, 01:08
by lrrpf52
mixelflick wrote:That 56 mile/F-15 figure is an old one though, no? These were Eagles used during Desert Storm, and don't take into account the newer AESA radars. Surely, they have the capability of looking beyond 56 miles??

If not, then carrying the AIM-120D is going to be self limiting. It reportedly has a range of 100 miles (or thereabouts), so a radar with roughly half that range is really selling the weapon short. I think I even read once that the new AESA's going into Eagles were MORE powerful than the F-22's AN/APG-77.

Am I off base here, or not understanding correctly?


There was an F-4E crew member who said the APQ-120 detected 737s out of Las Vegas at well over 200nm all the time back in the 1970s.

It all depends on RCS, atmospherics, altitude, which APG-63 we're talking about, etc.

Radar detection range isn't a static number.

Re: AN/APG-77 detection range

Unread postPosted: 28 Sep 2018, 22:46
by falcon.16
swiss wrote:
wrightwing wrote:
mixelflick wrote:That 56 mile/F-15 figure is an old one though, no? These were Eagles used during Desert Storm, and don't take into account the newer AESA radars. Surely, they have the capability of looking beyond 56 miles??

If not, then carrying the AIM-120D is going to be self limiting. It reportedly has a range of 100 miles (or thereabouts), so a radar with roughly half that range is really selling the weapon short. I think I even read once that the new AESA's going into Eagles were MORE powerful than the F-22's AN/APG-77.

Am I off base here, or not understanding correctly?

That's the MSA radar, not the AESA radar. It's also for 1m^2 targets.


But even for the APG-70, this performance is bad. The small RDI Radar from Mirage 2000 in the 80s comes close to that Range.

According to this document the APG-70 has a range of 185 km against a Air target. I assume 3-5 m2.

https://www.forecastinternational.com/a ... _RECNO=729


But the most powerful russian radar now inside the Su-35 S, the Irbis E, has a detection range around 200 kms for 3 m2 rcs. It is similar to the APG-70, from many decades ago.

Re: AN/APG-77 detection range

Unread postPosted: 29 Sep 2018, 01:25
by sinusoiddelta
mixelflick wrote:That 56 mile/F-15 figure is an old one though, no? These were Eagles used during Desert Storm, and don't take into account the newer AESA radars. Surely, they have the capability of looking beyond 56 miles??

If not, then carrying the AIM-120D is going to be self limiting. It reportedly has a range of 100 miles (or thereabouts), so a radar with roughly half that range is really selling the weapon short. I think I even read once that the new AESA's going into Eagles were MORE powerful than the F-22's AN/APG-77.

Am I off base here, or not understanding correctly?


I also recall reading (can’t remember where) something to the effect raptor pilots being jealous of the AN/APG-63(V)3 capabilities. Regardless, a 56 mile detection range sounds like a very cautious estimate, even for the pre-MSIP eagles.

An estimated detection range for a ‘medium sized’ target can be found in this document: http://www.dtic.mil/dtic/tr/fulltext/u2/a142071.pdf
Image

Re: AN/APG-77 detection range

Unread postPosted: 29 Sep 2018, 01:29
by wrightwing
swiss wrote:
But even for the APG-70, this performance is bad. The small RDI Radar from Mirage 2000 in the 80s comes close to that Range.

According to this document the APG-70 has a range of 185 km against a Air target. I assume 3-5 m2.

https://www.forecastinternational.com/a ... _RECNO=729


185km vs 3-5m^2 target. Not a 1m^2 target. Of course, no 4th generation aircraft (or earlier generations) are 1m^2, when carrying weapons and fuel tanks.

Re: AN/APG-77 detection range

Unread postPosted: 29 Sep 2018, 03:49
by wrightwing
falcon.16 wrote:


But the most powerful russian radar now inside the Su-35 S, the Irbis E, has a detection range around 200 kms for 3 m2 rcs. It is similar to the APG-70, from many decades ago.

That's 200km in look up mode (with 55% probability of detection), and ~170 to 180km in look down mode.

Re: AN/APG-77 detection range

Unread postPosted: 30 Sep 2018, 00:36
by swiss
falcon.16 wrote:
swiss wrote:But even for the APG-70, this performance is bad. The small RDI Radar from Mirage 2000 in the 80s comes close to that Range.

According to this document the APG-70 has a range of 185 km against a Air target. I assume 3-5 m2.

https://www.forecastinternational.com/a ... _RECNO=729


But the most powerful russian radar now inside the Su-35 S, the Irbis E, has a detection range around 200 kms for 3 m2 rcs. It is similar to the APG-70, from many decades ago.


True that. Same goes for SAR resolution. The APG-70 had 2.6m. Ibris-E has 3m. The more modern non AESA radar APG-68(v)9 has a resolution of 0.6m.

https://web.archive.org/web/20110526024 ... /APG68.pdf

And as wrightwing said. The probability of detection is much lower then in western radars (90%).

Re: AN/APG-77 detection range

Unread postPosted: 30 Sep 2018, 11:27
by falcon.16
swiss wrote:
falcon.16 wrote:
swiss wrote:But even for the APG-70, this performance is bad. The small RDI Radar from Mirage 2000 in the 80s comes close to that Range.

According to this document the APG-70 has a range of 185 km against a Air target. I assume 3-5 m2.

https://www.forecastinternational.com/a ... _RECNO=729


But the most powerful russian radar now inside the Su-35 S, the Irbis E, has a detection range around 200 kms for 3 m2 rcs. It is similar to the APG-70, from many decades ago.


True that. Same goes for SAR resolution. The APG-70 had 2.6m. Ibris-E has 3m. The more modern non AESA radar APG-68(v)9 has a resolution of 0.6m.

https://web.archive.org/web/20110526024 ... /APG68.pdf

And as wrightwing said. The probability of detection is much lower then in western radars (90%).


Yes, radar Captor from EF-2000 has 0,3 meters resolution SAR, it is 10 times less than better russian radar. And it is not aesa radar. I think Aesa Captor E will be around 0,10 meters resolution.