Advanced F-15 vs Eurocanards

[viper12]

Of course. But when i remember correctly, the RCS of the EF and Rafale is around one order of Magnitude lower then the F-15. And the IR signature from the Egale should be also higher?

Probably.

Note an RCS an order of magnitude lower may not yield that many benefits depending on the circumstances. Here's for example the radar equation : https://basicsaboutaerodynamicsandavion ... ermeasure/



If everything else is equal, dividing the target's RCS by 10 means the detection range is divided by 10^(1/4) = 1.78. So it's significant, but not as big as at first sight.

If you can add effective jamming, then check the burn-through range equation : https://basicsaboutaerodynamicsandavion ... asure-ecm/



With everything else equal, dividing the RCS by 10 means the burn-through range is divided by 10^(1/2) = 3.16. So that's already some more tangible gains.

But the F-15C got a much bigger nose : viewtopic.php?f=55&t=6094&p=374215

According to internet estimates Rafale's radar is circular with an array diameter of 550mm. The F-16's nose is elliptical with max dimensions of 740 x 480 mm. That works out to an area of of 0.238 m2 for the Rafale versus 0.279 m2 for the F-16. Compared to an area of about 0.385 m2 for the F/A-18 and Typhoon, 0.5 m2 for the F-35, and 0.785 m2 for the F-22 and F-15.

So assuming we're comparing an AESA-equipped F-15C, and the modules on the radars of both the F-15C and Rafale are equal (big assumption), and everything else is equal too, you'd then get around 3.3 times more modules on the F-15C's radar, which means also 3.3 times more radiated power.

If you've got an F-15C facing a Rafale, both effectively jamming and with the assumptions above, the F-15C would detect the Rafale at around 76% of the range at which the Rafale detects the F-15C. If you've got both fighters facing a target X with jamming, the F-15C would detect the target X at about 1.35 times the Rafale's detection range.

Also note that these aircraft RCS are affected by their external munitions and fuel tanks, probably in a noticeable way with non-conformal stores.

[talkitron]

It depends on just how advanced we're talking. Are we discussing a Silent Eagle vs Rafale and Typhoon? If so, an SE with -232 engines, AESA, IRST, EPAWSS, FBW, MLD/MAWS, would be a pretty steller performer. Of course that puts us into the realm of Geogen/Dale Brown, and hypothetical upgrades.

EPAWSS seems to not be sold to the Saudis and Qataris (who use DEWS), who are the only ones using FBW and MLD/MAWS. But if you combined the F-15SA with EPAWSS you could get everything on the list except the Silent Eagle RCS reductions and the -232 engines. The F-15SA uses F110-GE-129C engines, which seem nice.

It is possible the F-15SA has two IRSTs: one IRST in the Tiger Eyes / LANTIRN navigation pod and one IRST near the cockpit, the AN/AAS-42 or IRST21. The latter IRST21 product line is what is forming the core of Lockheed's Legion Pod, which won a contract from the USAF yesterday.

http://lockheedmartin.com/us/products/legion-pod.html

[talkitron]

Thanks viper12!

[swiss]

With everything else equal, dividing the RCS by 10 means the burn-through range is divided by 10^(1/2) = 3.16. So that's already some more tangible gains.

But the F-15C got a much bigger nose : viewtopic.php?f=55&t=6094&p=374215

According to internet estimates Rafale's radar is circular with an array diameter of 550mm. The F-16's nose is elliptical with max dimensions of 740 x 480 mm. That works out to an area of of 0.238 m2 for the Rafale versus 0.279 m2 for the F-16. Compared to an area of about 0.385 m2 for the F/A-18 and Typhoon, 0.5 m2 for the F-35, and 0.785 m2 for the F-22 and F-15.

So assuming we're comparing an AESA-equipped F-15C, and the modules on the radars of both the F-15C and Rafale are equal (big assumption), and everything else is equal too, you'd then get around 3.3 times more modules on the F-15C's radar, which means also 3.3 times more radiated power.

If you've got an F-15C facing a Rafale, both effectively jamming and with the assumptions above, the F-15C would detect the Rafale at around 76% of the range at which the Rafale detects the F-15C. If you've got both fighters facing a target X with jamming, the F-15C would detect the target X at about 1.35 times the Rafale's detection range.

Also note that these aircraft RCS are affected by their external munitions and fuel tanks, probably in a noticeable way with non-conformal stores.

I know garrya's great site. But its not easy do understand for me, because the language barrier and im not a ingenieur.
So thanks a lot for your explanation Viper12.

But i did a mistake with the RCS. I was meaning 2 orders of magnitude ( 0.1-0.3 m2 vs 20-30m2 ).

So that means the APG-63(V)3 and AN/APG-82 have around 2700 modules.

[swiss]

So assuming we're comparing an AESA-equipped F-15C, and the modules on the radars of both the F-15C and Rafale are equal (big assumption), and everything else is equal too, you'd then get around 3.3 times more modules on the F-15C's radar, which means also 3.3 times more radiated power.

If you've got an F-15C facing a Rafale, both effectively jamming and with the assumptions above, the F-15C would detect the Rafale at around 76% of the range at which the Rafale detects the F-15C. If you've got both fighters facing a target X with jamming, the F-15C would detect the target X at about 1.35 times the Rafale's detection range.

Also note that these aircraft RCS are affected by their external munitions and fuel tanks, probably in a noticeable way with non-conformal stores.

I know the Site of garrya. Its a fantastic site. But its not easy to understand for me. Because of the languages barrier and im not a ingenieur.

So thanks a lot for the explanation. viper12.

But i did a mistake for RCS. I was meaning 2 orders of magnitude (0.1-0.3 m2 vs 20-30m2).

So if the RBE2-AA has 840 Moduls, that would mean the APG-63(V)3 and AN/APG-82 must have ca. 2700 Modules?

But as you said, the Rafale have probable a advantage compere to a F-15 to detecting each other.

[viper12]

But i did a mistake for RCS. I was meaning 2 orders of magnitude (0.1-0.3 m2 vs 20-30m2).

So if the RBE2-AA has 840 Moduls, that would mean the APG-63(V)3 and AN/APG-82 must have ca. 2700 Modules?

But as you said, the Rafale have probable a advantage compere to a F-15 to detecting each other.

2 orders of magnitude may be true with clean aircraft with the lowest RCS estimates of the Rafale, but I think it's closer to 1 order of magnitude, especially with external stores.

For the number of modules on the APG-63(V)3 and AN/APG-82, I've never seen any estimate of the number of modules.

[geforcerfx]

So if the RBE2-AA has 840 Moduls, that would mean the APG-63(V)3 and AN/APG-82 must have ca. 2700 Modules?

But as you said, the Rafale have probable a advantage compere to a F-15 to detecting each other.

Most quotes I have seen is around 1500 modules, so similar in count to the F-35 and Typhoon (and Pak Fa) just a larger array, no idea what the power would be.

[zero-one]

Can you post links to the data you refer to? I appreciate you actually citing data rather than only speculating.

I do agree that, for the F-15E, the conformal fuel tanks add weight compared to an F-15A/C/J not using either conformal or more traditional external fuel tanks. But a combat load without fuel tanks seems unlikely for all the aircraft in question.

Tons of info available here
viewtopic.php?f=55&t=25735&p=363657&hilit=comprehensive+F+16+F+15+F+35#p363657

but most notable would be the graph posted by Sprts showing the Stability and Drag index differences between the F-15C and E.

Basically the F-15C still has the upper hand and it translates to air to air performance advantages for the C version

[swiss]

2 orders of magnitude may be true with clean aircraft with the lowest RCS estimates of the Rafale, but I think it's closer to 1 order of magnitude, especially with external stores.

Yes this makes sense. What would have a F-15 with external stores?

@geforcerfx: Thanks for clarification.

I read on the " Hush-Kit" that the APG-63(V)3 is the third best Radar in the world.

https://hushkit.net/2016/04/24/top-ten-fighter-radars/

[zero-one]

I read on the " Hush-Kit" that the APG-63(V)3 is the third best Radar in the world.

https://hushkit.net/2016/04/24/top-ten-fighter-radars/

Hushkit is a very nice blog and I'm a fan of it myself, the author does his research in the best way he can. however it is not an authoritative source of info with access to classified info. Though he does seem to have limited access to deep unclassified info through the various interviews he has been conducting.

However he also puts this disclaimer to his claims:

The order is meaningful, but certainly not definitive: adhering to the top 10 format always requires a simplification. Much is open to interpretation so I am happy to receive corrections and additional information from reputable sources.

so take the list as it is, a good insightful read, but not definitive.

[white_lightning35]

2 orders of magnitude may be true with clean aircraft with the lowest RCS estimates of the Rafale, but I think it's closer to 1 order of magnitude, especially with external stores.

Yes this makes sense. What would have a F-15 with external stores?

@geforcerfx: Thanks for clarification.

I read on the " Hush-Kit" that the APG-63(V)3 is the third best Radar in the world.

https://hushkit.net/2016/04/24/top-ten-fighter-radars/

I don't know if I would trust blog rankings like that, usually. It doesn't seem wholly inaccurate, but doesn't seem that it is incredibly detailed. It keeps repeating that meme that the apg-81 has 1200 tr modules, and from what we hear, the apg-81 is in many respects superior to the apg-77.

[zero-one]

I don't know if I would trust blog rankings like that, usually. It doesn't seem wholly inaccurate, but doesn't seem that it is incredibly detailed. It keeps repeating that meme that the apg-81 has 1200 tr modules, and from what we hear, the apg-81 is in many respects superior to the apg-77.

As far as I know that is accurate, the F-35 has approximately 1,200 T/R modules. While the APG-77 has approximately 2,000.
Much of the advantages of the APG-81 is in it's Air to Ground modes and more advanced hardware. But the current APG-77, the "V1" uses the APG-81's hardware and also has the advanced A-G modes.

[white_lightning35]

I've seen this picture floating around here. Not sure if it's a accurate representation of the real thing.

[swiss]

Hushkit is a very nice blog and I'm a fan of it myself, the author does his research in the best way he can. however it is not an authoritative source of info with access to classified info. Though he does seem to have limited access to deep unclassified info through the various interviews he has been conducting.

However he also puts this disclaimer to his claims:

The order is meaningful, but certainly not definitive: adhering to the top 10 format always requires a simplification. Much is open to interpretation so I am happy to receive corrections and additional information from reputable sources.

so take the list as it is, a good insightful read, but not definitive.

I fully agree with your opinion. I would say better then the most sites in the net about military aviation. And near the optimum, for a source that as no access to classified information. My most favorites post are the interviews with fighter pilots.

@white_lightning35: I think this picture is from a user in this Forum.

[SpudmanWP]

I've seen this picture floating around here. Not sure if it's a accurate representation of the real thing.

That is the same array that has been shown on a BAC111 and on a factory floor F-35, so yes, it's a production array. As to the count, since I'm the one who did it, yes, it's accurate too