wrightwingYes, B2’s RCS is much larger than Cessna’s but differently distributed, so it only appears to be smaller.
So for practical matters(i.e. what the search radar sees), the B-2 appears much smaller, which supports my point. Shape is more important than size.
wrightwingI see, in general, the same aircraft.
You’ll note(well now you will anyhow) that I said IF they achieved that, THEN there were more than “minor” changes made.
So back to my point – there is no data whatsoever other than schmuck-talk online.
The schmuck talk was what I was referring to. The serious sources being journals, colleagues, etc… that felt the RCS was competitive or superior.
MMI? Man-Machine Interface? The PAK-FA will have very advanced AI and will have autopilot features you probably won’t find on any F-22 or F-35. That will certainly be part of “MMI” for the T-50’s side.
Which remains to be seen in operationally representative form.
Don’t even start on pretending the American AESA will certainly be superior. That’s the kind of BS that just doesn’t stick. Size is gonna matter though, I promise. 😉 😉
The US T/R modules are several generations more advanced, and that’s not even taking the back end into consideration.
EODAS will be compensated for with multiple radars and a solid IRST. Not to mention something more MAY be revealed later for the T-50.
Not without some major redesigning, and if you’re talking about the L band arrays, then I wouldn’t hold my breath in terms of being used to detect aircraft.
MADL? What is so fancy about a data link? How can you even suggest the T-50 will not have something similar? Even more interesting, just how good will it be when L-band AESAs come around?
We’ll have to wait and see, though the LPI datalink tech won’t be frozen either.
“Spiral upgrades” can be given to a T-50 too.
Like the ones that previous Russian Air Force fighters have continuously received?:rolleyes:
The current engine might be 34K – 35K lbs of thrust, but when the new engine is released – what are we going to see? A T-50 @ Mach 2 @ mil thrust?
The numbers I’ve seen are M1.3 with the current engines, so M1.7-1.8 with the new ones is probably closer to the ball park.
New jammers, etc – all that can be installed there too.
That won’t address every issue, as a larger RCS will have to be overcome.
The F-22 could be flying forward, with the enemy radar emitting from slightly below in altitude from the side (from any aircraft) – getting a near perpendicular return.
And I suppose that’s why every US plane(including ones with AESA radars) have had so much success detecting F-22s, seeing as how they’re so vulnerable from this aspect.
wrightwingGood post there. You have hit the nail squarely on the head, m. tc canard.
The very fact that the USAF doesn’t allow any other nation to have any opportunity to pick up transmissions of the “lpi” radar confirms that they don’t want the emitting patterns to be filed away in any threat library.
This strongly suggests that the vaulted “virtual undetectability” of the “lpi” is little more than a marketing tool.
Low probablity of intercept, sure for legacy kit, but with the right modern kit…maybe not so.
Part of LPI is in being hard to detect. Part of LPI is in being hard to recognize/identify. If your threat library has signal patterns stored, it can help solve part of the puzzle. Of course the signal patterns aren’t constant in the event that one was compromised.
Unless of course they are having a great big laugh at everybodies expense and are actually flying around with the 77 on at all times and nobody is picking it up…;):diablo:
😎
wrightwingthrid party targeting is another thing. and besides the point while discussing radar/jammer relations.
The third party doesn’t necessarily have to be a an AWACS. It could be one of the F-22s(or AESA equipped F-15C for that matter) sending info, while the rest of the flight was in EMCON. The plane that’s emitting could even change periodically to keep things more confusing, and make jamming even more difficult.
the emitter (we’re in no awacs scenario, or the fighters would not need their radars at all since they’re all L16 equipped) is flying in a hostile area and has to count on his radar to see what’s ahead of him. LPI or not, how do you decide at what power you emit? if you haven’t detected anything yet, you don’t know whether there’s empty sky ahead of you or an aircfraft that’s simply too far out to be detected with its RCS caracteristics.
If you have a scenario where you need say, X watts of power emitted to see an aircraft. retaking my previous example:
-you emit X watts
– on the way towards the target, you have a certain percentage of dispersion and signal loss, let’s call it D1
– you have (X-D1)/20 watts reflecting back towards you
– and you have again the dispersion and signal loss percentage of the return signal, we’ll call it D2
– the minimum return signal you detect, will be (X-D1)/20-D2now, while you get that small return, the receiver will be illuminated by a signal that’s (X-D1) and that’s it. which, in that example, is over 20 times stronger than what your radar will get in return. So, while LPI sounds nice on paper (signal barely above noise level), it tells only half of the story.. it’s barely above noise level for the hunter, but the guy it’s aimed at gets a much stronger signal, and that’s the point I was making. It could work against a target that uses outdated ECM suite, but a more modern one, especially if it managed to record a pattern of your radar, could become quite difficult to detect. And that’s also why the USAF agreed to go against the french in the UAE on condition that it be a WVR fight with F-22 radar off and SPECTRA off… the last thing the US would want is SPECTRA recording F-22s radar patterns and include it in its librairies.. if it was ever sold to a country the US declare war a few years later, the thing may prove quite costly for american fighters
It’s not just X number of watts emitted though. It’s antenna gain/sensitivity, filtering, signal processing power, available memory, the amount of time required to detect a recognizable pattern as being a hostile signal, and then being able to successful degrade it enough to break the kill chain.
wrightwingWrong . :diablo:
-1) The RWR is always the first to get the ping since the reflected signal did not travel its way back yet 😀
That’s not the point he was making though. The ping will make it back before the signal is analyzed, identified, and the jammer sends a signal of its own.
-2) The RWR will get the ping even if the signal is very low .
Example : an APG-77 will not see a Rafale at 200km (reflected signals are too small) but Spectra will acknowledge the “pings” .
If the Rafale were 200km away, it wouldn’t be considered a threat yet, first of all, as the APG-77 prioritizes targets by range, and the amount of time that they are illuminated and subsequently tracked. Secondly, it would take more than 1 ping to correctly identify what the ping was, much less respond to it.
In this scenario , the Rafale pilot can simply stay outside the detection range of the APG-77 for minutes on while Spectra is “learning” the techniques used by the adverse radar . After few minutes of this “electronic deciphering” , the DRFM techniques (if used) will have a great chance to follow the LPI radar .
Cheers .
This shows a fundemental misunderstanding of how the APG-77 works. It doesn’t send out constant broadcasts to the maximum range that it can achieve. It might do a brief periodic sweep to see if anything’s out there, but until the target gets within a certain distance, its track is only periodically updated. It doesn’t get a constant track until it’s within range to engage.
Secondly until the signal is identified, and POO established, it hardly knows where it needs to stay, in order to be out of detection range.
wrightwingOh, crap…and I thought it was. 😀 …oh well, I guess you know better…
:rolleyes:
So a B-2 should have a much larger RCS than a Cessna right?
wrightwingRCS – See, no, you don’t know that. If you do, you better have a real good, scientifically derived report somewhere for everyone here.
Aside from youtube comments, I’ve yet to see any serious source that thinks that without major changes, the T-50 will be as stealthy much less stealthier than the F-35.
Avionics – Based on what? A few extra toys? How about the far superior coverage of the 5 radars the T-50 will have?
MMI
Latest Gen AESA(which has more advanced T/R modules)
EODAS
MADL
Spiral upgrades(i.e. NGJ, DIRCM, space for additional AESA arrays for even wider coverage, etc…)
See I don’t completely buy the “angle of the aircraft” type argument entirely.
What about the angle of the emitter? If you are level with a Flanker and hitting him with radar from the side, you get a good reflection.
If you hit the Raptor from the bottom, those tails will reflect directly at you. Maybe less so, but they will.
Makes sense why the T-50 went with such small tails for side stealth.
It’s the angles of the aircraft, moreso than the angle of the aircraft, as well as the coatings, and internal layouts, that help minimize returns. There are very few instances where an F-22 would be doing a verticle climb, while heading towards an enemy radar, so that’s not a particularly realistic situation. In any event, the bottom of the Raptor would provide less return than a Flanker.
wrightwingHow large is the reflection from the engine then? How could it possible be more than the total “squared” area of the actual intake?
RCS isn’t directly related to the size of the object.
So the minor modifications of the Su-35S took the Su-27 from 15m2 to 3m2?
I’d say if they were able to achieve 3m2, then there were more than some “minor” modifications.
wrightwingo 26,664 lbs/29,996= .89 or ~11%
o we do know that the F-135 is rated at 43k(and possibly higher)
o the F-136 is 40k lb class
o the TF-30 isn’t what we’re discussing. If you want to discuss more recent P&W products, then the F-100 series(especially) the -220/229 models have been more reliable than the GE F-110.
o using F-35 funds to develop the F-136 will cut the buy, and create a death spiral, as well as increasing costs by having a more complex supply chain. If GE/RR can get funding that won’t adversely impact the F-35, get a mature product, and demonstrate that it should be considered then fine.
wrightwingDRFM is useless against a frequency agile radar because the radar always gets a clean first ping at the new frequency. Change frequencies every few milliseconds and the frequency agile radar is pretty much unaffected by DRFM. However, broadband noise jamming is an appropriate counter to a frequency agile radar, but you run the risk of sucking up an anti-radiation missile, such as an FT-2000.
And you still have to have enough power and emitters to cover that broad band.
wrightwingFor the sake of illustration, if you have 5% energy hitting the aircraft return in the direction of the emitter, that means that the energy hitting the target will be 20 times higher than the energy reemitted to the source. Now, even if the source want a very low level coming back, it still has to travel all the way back an be sufficiently powerful to be detected above the noise (so, the signal hitting the aircraft in such case would need to be at least 20 times stronger than the environment noise, and you have to add some more since the return signal has to have the energy to travel all the way back to the emitter again).
Here’s the thing though- how quickly can the filter identify a hostile signal vs. the LPI radar finding its target? It doesn’t take long to acquire a target track with an AESA radar, and if the targets are at long range they only get periodic updates until they get close enough to be more of a threat. Then factor in third party targeting, so not every platform is emitting(i.e. the emitter can be the hunter, while the other birds are the killers).
wrightwingAbout the Navy: it is abundantly clear that this admiral was towing the DoD line – anything else would be career suicide – and no fat industry job post-Navy. The DoD wants to kill it not because it’s a bad engine, or a bad idea to have an alternative – it needs to save money on the JSF, and this is the easiest place to start.
The point is this: you have the F-35C which is at least 15% heavier than the F-35A – already a heavy single engine fighter. You power both versions with an engine that produces the same amount of thrust.
The F-136 doesn’t promise more thrust though, and the F-135 has a lot room for growth, in both thrust and efficiency, and the C model is only ~12.4% heavier.
I find it interesting that F-35 supporters would want to deny an option that has the promise to make the aircraft a better performer.
That’s a strawman argument.
Pratt had a sweetheart deal with this program, and they have returned the favor with a 2b overage. Pratt also has a history of delivering engines that the customers were dying (sometimes literally) to get rid of: the TF30 comes to mind.
That’s another strawman argument.
The services recognize that engine competition is good: hence the development of the GE F110 alternative fighter engine to supplement the P&W F100. Incidentally, the F110 powers over 3/4 of the F-16 fleet
Let’s see some sources for that claim.
I take your point about the current development status of the F136 – there are 7 F136’s in development, but that phase is nearly complete. It would be prudent to complete testing and see where the engine stands vis a vis the F135.
The F-135 is based upon a proven design, and there are hundred of thousands of hours of operation to verify performance, reliability, durability vs. hundreds to a few thousand hours tops on the F-136. The F-135 already is in the 43k lb thrust class(and there’ve even been the occasional brief showing it at 48k lb). Additionally, it demonstrated over 52k lb of thrust in earlier testing.
wrightwingThat’s correct, but using sweep jamming you have two issues. Agility of the jammer and power of the jammer. Jammer should be much more agile than radar to sweep between all used frequencies quickly(and this also needs power). Maybe using several jammers sweeping in a different order is a way to effectively jam AESA radar. Also several high-power jammers doing basee jamming might increase effectiveness of jamming, but still – to do it as effective as DRFM jammer vs non-agile radar would need enormous power.
That, and you make yourself pretty visible to anybody that’s listening.
wrightwingBoth F-22 and F-35 have huge tails. Much larger than T-50, and comparable to Su-27, for that matter, even if canted outwards.
The angles matter, among other things.
wrightwingThat doesn’t pass the Occam’s Razor sanity check though. There are too many assumptions that need to be made, for that to be a tenable argument. Additionally, the F-135 is not maxed out by any stretch, and the F-136 is nowhere near the level of refinement level that the -135 has reached at this point. Lastly, it’s very amusing to hear of remarks about the -135’s cost, when the cost to get the -136 up to the same level of system maturity, etc.. would be considerably more.
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