Sukhoi Su-30MKI
- Thread starter Ashwin
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Frankly the 177S has just been introduced by Russia somewhere last year IIRC. It's difficult to get a grip on everything the Russians claim & the Russians make a lot of claims.
My point remains. Are we going in for a new engine only for 150 odd MKIs , obviously discounting the 120 odd MKIs we'd be re fitting with the AL-31?Is it economically feasible ? I ask for we don't even know which series of MKIs are undergoing those engine refits ?
That would've given us insights into whether the IAF plans to re engine the entire fleet of MKIs or leave out the first 30-40 MKIs we got from Russia way back between 2004-08 which'd be retired early as was previously speculated out here .
Yes and no, depends on the objective and design of the antennas relative to what it is being compared to.
Typically photonic radars will require more power due to immaturity of the tech and potential inefficiencies compared to the most capable versions of GaN.
We have to wait for real world applications to show up before we can say for sure.
You can drop the sir.
Hmm. I missed this news.
We shouldn't go for anything that they themselves don't plan on operating. If it's a derated AL-51F and ends up on Russian Flankers, then we can look into it.
Literally no stakeholder ie MoD, user IAF or HAL has yet shown any willingness for any engine upgrade. Well we can discount HAL cos they will do what is told by the MoD. But still no one shown any will to upgrade the engine and yet we keep clamouring for this new engine. I do not get this obsession. If you want to upgrade with a new engine, you also need to set up the supply chain, new rigs etc. Given rus themselves are plagued by the same issue, why would IAF be interested ?
It's the tentative designation for the "5th gen" advanced engine, designed to be a drop-in replacement for AL-31/41F-1 and pitched to export Flankers customers. The Russians showcased it during the Zhuhai Air Show.
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This X‑band AESA radar, with its octagonal shaped rectangular central section and chamfered corners (around 960 mm × 880 mm, ~0.825 m² aperture), actually has a much higher T/R module count potential than what is usually publicized..........In my view, it’s possible to fit roughly 3,665 T/R modules on it using the most advanced packaging technology available today...........assuming each GaN T/R module outputs about 25 W peak power, that gives a total peak power of around 91.6 kW, which is quite achievable with modern tech...........With this setup, I’d estimate the radar could detect a 1 m² RCS target at well over 500 km under good conditions, which is a huge leap over older designs..........If we instead go with the more commonly cited 2,700 T/R module count, producing about 67.5 kW peak power, then I’d put the detection range for a 1 m² target at around 465 km.
Depends on the packaging of the TRM. The currently advertised one puts it around 3 cm2 compared to RBE2's 2.5 cm2 for GaAs. Uttam's GaAs are at 3.7 cm2 or so. APG-81's GaAs is at 3 cm2. European tech was more advanced back then, that's why their comparatively smaller radars carried more TRMs, 1048 on RBE2 and ~1500 Captor-E.
If Virupaksha uses the latest GaN tech, it can climb to 4200-5600 TRMs with currently achievable tech (2 to 1.5 cm2), or at best 3300 with 2.5 cm2.
But MKI cannot power that many TRMs or even an individual TRM of 25 W. It's apparently using a SiC substrate which is unlikely to have a PAE over 40%. A more suitable TRM with SiC would be 12 W, maybe 15 W, so nothing more than 30 or 40 kW peak power.
The main selling point will be a digital design with multiple receiver channels, so max detection range is subject to software and processing at this point.
Also, we gotta remember that the new vapor cooling system for the radar maxes out at 10.5 kW. With 30% safety margin, we can only use 7-8 kW. So 25 W is out of the question, the VCM has to be 20+ kW at that point. So TRM can only output 12 W or 15 W at 20% duty cycle with the 30% safety margin due to our high ambient temperatures. Ethyl glycol at 40 LPM gives us up to 25 kW of cooling. Assuming 40% PAE, 2700 at 12 W needs almost 20 kW of heat removal, so it's within the margin. At 15 W, 27+ kW heat removal is just beyond the peak potential of the VCM, so it's unlikely to be 15 W either. At 25 W, it's 45+ kW, so that's obviously impossible too.
So 12 W TRMs up to 3200 (or 2700) or 15 W up to 2400, that's the best we can hope for right now. And at 40% PAE; if it's lower it will become a problem. At 50% PAE, we can use 15 W TRMs too beyond 2700. So this is where we can draw the limits of the radar.
2400 TRMs at 12 W essentially uses the same power as Bars though.
Now the only question is if the AL-31FP has a 60 kVA power generator or up to 100 kVA. The latter is necessary to operate the radar and all other electricals at peak power simultaneously, especially at high altitude where power is derated.
177S for MKI is now almost a lock if Russians accept our conditions(which they should, me thinks). Let's see.
Would it be possible to fit a ram air turbine to MKI (like they do to commercial airliners like B787 or even the F-18 Growler's EW pods)? That could provide more juice to operate high power radars without an engine change. Has something like it ever been done before?
power is restricted at 15-20 W per tr module, i read it somewhere in hal-drdo slide that the reason to restrict is if they chase high power, then that would take more time for developing an even more powerful cooling system. current cooling allows for 2400 trm with power in between 15-20 w.
we can take the advantage of their economic situation and get that 5th gen engine and then continue our iterational development of materials on top of it. then let gtre develop the 5th gen engine on its own with a sweet budget. in this way when amca engine comes, it would be much more advanced as compared to al51 in materials.
but logical option would be to do a jv with an engine maker who can give us the know how/why and design philosophy of advanced engines and production techniques.
Just because a radar has X number of 20W modules does not necessarily mean that all of them will or can be operated at 20W at the same time.
One can use smaller clusters of TRMs at a high power state to generate beams to serve specific purposes, and switch to a predetermined lower power state when operating the whole array at once. Ideally, yes you'd want your cooling system to be able to handle all the TRMs at their rated output, but not everyone has cooling systems that good (remember, the cooler has to use power as well).
But there are ways to work around this while obtaining at least some of the benefits of higher-rated TRMs. Remains to be seen what we go for.
One can use smaller clusters of TRMs at a high power state to generate beams to serve specific purposes, and switch to a predetermined lower power state when operating the whole array at once. Ideally, yes you'd want your cooling system to be able to handle all the TRMs at their rated output, but not everyone has cooling systems that good (remember, the cooler has to use power as well).
But there are ways to work around this while obtaining at least some of the benefits of higher-rated TRMs. Remains to be seen what we go for.
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So theoretically Virupaksha even wirh AL31 can allocate a peak power close to what @South block said but only for a small number (say 200?) TRM modules? This could make it still be very formidable against LO targets such as J20 and J35.
what is going to cool that ? you also have to think about the optimum performance under specific condition.
If only 200 out of ~2700 are operated at 20W (or 25W, whatever), the peak output will be far lesser than what he's talking about. Cuz the remainder TRMs have to operate at very low power states to compensate. It'll also be down to how much heat the cooling system can effectively remove from each TRM over a given time period - just the overall heat removal amount doesn't give us the whole picture.
No.
Pumping more & more power through X-band is a very inefficient way of obtaining better ranges against LO/VLO aircraft. The kind of power increase we're talking about will barely make any difference whatsoever to detection range against aircraft specifically designed to defeat X-band.
Far more efficient results can be achieved through novel signal-processing algorithms, and by the fact that we're gonna be moving to AESA which is broadly less susceptible to ECM-induced degradation and even otherwise is better able to distinguish signal from background noise.
The use of small beams using full rated power of TRM has very specific applications: like providing targeting cues for missiles at longer ranges while still maintaining LPI aspects of the radar. But you need pre-existing knowledge of target presence & general location to do that. Against a LO/VLO target, that can only be provided by either AEWs/ground radars that use S or L-band arrays, or as the case may be, passive sensors.
If your non-stealthy fighter is using its own X-band to perform wide sector scan to find LO/VLO targets, it'll be killed long before it manages to find any.