Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

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brar_w
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by brar_w »

Ganesh_S wrote:
brar_w wrote:
These are not nomenclature aspects alone. Do you think the IAF, the primary customer, would not have provided a range for weight and size that it desires?
Sir pardon my layman ignorance and let me phrase it this way- if supposedly IAF has specified supercruise as a must have above all criteria set without compromising on stealth and there are two approaches to solving this both being a function of design and power.

1. Having a fundamental design for a given thrust with tradeoffs being addressed later.
2. Designing an aircraft without any tradeoffs except supercruise wherein the supercruise aspect is dealt later with a higher powered engine

Now my concern here is, as there is a diminishing return in both approaches which one of these is likely to lead towards an optimal design (or safer approach).
There is wiggle room in requirements and you can attribute different importance to each criteria. For example, a simpler IWB without the flexibility of carrying large bombs or cruise missiles for example can help. Same with range and internal fuel. All these things impact performance. If you want a large volume payload designed around larger diameter weapons, and want a fair number of them, while also requiring medium-long range then something has to give and most often it is a larger engine, larger aircraft in order to meet other performance.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by Ganesh_S »

if AMCA acheives supercruise with 414 ins6 in a clean configuration with just a2a weapons in IWB and fuel enough for a decent range then we should be close to the optimal design point. Else we might end up in a spiralling saga wherein the point of diminishing returns might arrive too quickly with no room for the higher thrust engine to compensate for higher payload and supercruise ability.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by nachiket »

brar_w wrote: It is not meaningless as it gets to what types they intend on replacing, and missions they intend to use the AMCA to recapitalize. So think of the sort of range payload performance of the aircraft the AMCA is to replace and see what the IAF may want. That impacts the size and weight requirements. There is no such thing as a light stealth fighter because it would be too compromised (ROKAF shut that DAPA suggestion down in Korea for example). There is essentially a Medium class aircraft, in the ballpark of KF-X or F-35 and there are heavy class fighters like the J-20, F-22 and Su-57.
I understand. I was only pointing out that the "Medium" designation has a rather wide scope in the Indian context.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by Indranil »

Brar sahab,
You have hit the nail on  the head. Let me add my observations.
1. To the best of my knowledge supercruise is a trait that IAF wants to have. The good thing is that the 414 can handle supercruise. ADA will have to design the intake properly to obtain the inlet conditions at the compressor face for supercruise. From my understanding this design has progressed well within ADA and the reviews with GE have been positive. I don't know whether the EPE is designed to handled supercruise, but can't imagine why not. 

2. IAF is not thinking of AMCA as a replacement for an aircraft or set of aircrafts. Frankly, there are no airplanes in IAF's inventory which does AMCA's role, albeit stealthily. Rafale is just entering service and too few in numbers for AMCA to replace.

3. IAF is distributing the entire gamut of roles between MWF and AMCA. That's why you see MWF lying somewhere between the light and medium category, and AMCA lying somewhere between a medium and heavy category.

4. If there will be no FGFA, then AMCA will be taking on the role of air dominance. All indicators point in that direction. Even in the latest spec release, the focus has been on close "combat capability" and "supersonic persistence" citing high TWR. Clean TO is 20 tons and at 220 kN of thrust, the intended TWR at clean take of would be greater than 1.1. I think they will have supercruise with caveats, e.g. cannot supercruise with full internal fuel or punch through the Mach barrier using limited AB and then sustain on military power. 

5. My guess is that they will compromise on the stealth in strike missions as well. It is unlikely to carry cruise missiles internally, or two large diameter bombs. The target is two HSLD +  two A2A internally. 

6. There are some hints on internal fuel too, probably settling in the range of 7-8 tons of internal fuel. That  should provide a combat radius of 600 Nms. Given India's geography and neighbors, that should be enough. 
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by Katare »

I have a totally different take on it, FGFA has been thrown out because IAF/GoI have finally grown a pair each to refuse friendly invitation from Russia to be it’s bitch or a guinea pig again. FGFA wasn’t the deal we needed or wanted.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by brar_w »

Indranil, all great points and thanks for your insight. A few replies -
Indranil wrote:2. IAF is not thinking of AMCA as a replacement for an aircraft or set of aircrafts. Frankly, there are no airplanes in IAF's inventory which does AMCA's role, albeit stealthily. Rafale is just entering service and too few in numbers for AMCA to replace.

So the IAF will physically not replace any aircraft with the AMCA? What about the mission sets currently performed by the aircraft that will be retiring from service between 2030 and 2050?..Would the AMCA not be tasked with taking over those missions? Operational realities require an analysis of the capability you are trying to recapitalize and seeing how the incoming capability will take over - even though, the way it does that mission may be different. One could have envisioned a silver bullet 5GFA force (used like the F-117 for example) in the 2020's but if the AMCA is going into production and service for the post 2030 then it will need to proliferate into the IAF far deeper than that given how A2A and IADS capabilities of the primary opponents (China) is going to evolve over the next 30 years.
Indranil wrote: If there will be no FGFA, then AMCA will be taking on the role of air dominance. All indicators point in that direction. Even in the latest spec release, the focus has been on close "combat capability" and "supersonic persistence" citing high TWR. Clean TO is 20 tons and at 220 kN of thrust, the intended TWR at clean take of would be greater than 1.1. I think they will have supercruise with caveats, e.g. cannot supercruise with full internal fuel or punch through the Mach barrier using limited AB and then sustain on military power.
Of course you make do with what you have. But it will be difficult to replace "FGFA requirements" (assuming the IAF demanded a set of requirements from Russian side) with the AMCA. Of course, it will still do the mission but will have to do it differently. Even the F-22 and Su-57 will use AB to punch through the transonic range even though they can (eventually if not at baseline for the PAKFA) do so without it. You have to stay efficient and manage your fuel and zipping past the transonic region is going to get that.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by srai »

The timeline is such that the AMCA will end up replacing Su-30MKI (earliest lot over 30-year old by then).

Between 2020 and 2040:
MiG-21 Bison (6 sqdn) —> LCA Mk.1/1A
MiG-29 UPG (3 sqdn) —> LCA Mk.2 MWF
Mirage-2000 (2-3 sqdn) —> LCA Mk.2 MWF
Jaguar D-II/III (4 sqdn) —> LCA Mk.2 MWF

Between 2035/2040 and 2060:
Su-30MKI (earlier ones) —> AMCA
Su-30MKI (latter ones) —> AMCA/AURA UCAV

LCA Mk.1/1A/MWF and Rafale will also require replacements post 2050. Maybe AURA UCAVs, or a 6th-Gen.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by Indranil »

Katare wrote:I have a totally different take on it, FGFA has been thrown out because IAF/GoI have finally grown a pair each to refuse friendly invitation from Russia to be it’s bitch or a guinea pig again. FGFA wasn’t the deal we needed or wanted.
With all due respect sir, that is bias speaking. From all accounts, PAKFA will be the top dog of air dominance in the next 2 to 3 decades. I dont think ANYBODY worth his salt doubts its A2A prowess. Its slow speed and high speed maneuverability is out of this world. Only the F22 come close. And if it is not already evident, I am big F22 fan. You will be able to see the PakFA and it will be able to see you too. Except, you can't match its agility or maneuverability. People will take down PAKFAs through superior strategy and numbers. No other way.

Coming to Russian wares, they are not untouchable. We are buying their stuff where it is world class. The S400 is one such example. We are buying it inspite of immense international pressure.

No other 5th generation program fits India's bill. The fallout in the case of FGFA was on workshare. India was not getting the research ROI on the RnD dollars.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by brar_w »

Not a single operational squadron of the Su-57 currently exists. When one does, it will be some time still before it gets a definitive engine and other things that are promised. It may well be closer to 2030 before enough iterative development is done to a point that it is a refined product with all the bells and whistles that the Russians actually wants on it. Things like "level of stealth", manufacturability (QC) and maintainability of stealth won't be answered till there are at least a 80-100 or so operational aircraft flying (unless one is totally comfortable with attributing a capability of Stealth and production of stealth to them without any past experience or operationalized capability) a few hundred hours annually. That may not happen till into the 2030's at a time when the F-22 replacement would be flying already (not to mention what the F-22 and F-35 would evolve to then). I'd hold off on claiming that the PAKFA will be the top dog of A2A fighters for the next 20-30 years based on a dozen or so test beds and prototypes and an abysmal production rate and induction schedule (average induction rate of < 10 aircraft a year over the next decade with zero exports). 6th generation fighters will likely be operational before the first 100-120 or so operational Su-57's are fielded into front line units. It is just too late in the game in terms of schedule to claim the top dog podium for that long or for any duration. F-22's were rolling from the production factory to operational squadrons more than 15 years ago. It is a more than capable Flanker replacement for the Russian Air Force and gets them into the 5GFA market which is important given many Flanker users would want to replace their aircraft in the coming decades. But as a contributor to their airpower, and as a complete product, it is unlikely to be a big influence till many years from now.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by LakshmanPST »

I guess India will (and should) start a new program for a 5++ or 6th Gen fighter may be after 2025 (when Tejas Mk2 will finally enter production and design team will be free)...
They would probably include all the 6th Gen stuff like Swarm drones, Unmanned wingman etc... I think India already started working on some of these... And many 5th Gen technologies will be developed for AMCA anyway....

I assume Su30s will start retiring from 2040s-late2060s... So, 20 years is a good enough time to develop one... Even if it is ready for production by 2050s, it will still be perfect time to replace majority of Su30 fleet...
-
I believe these jets would be the ideal replacement for Su30s, rather then going for Su57 (which will be 30 years old technology by then)...
In case IAF has Heavy Air superiority/Strike requirement in the combat scenario of 2nd half of this century, they should include it in this program...
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by Prasad »

We're not going to build a heavy fighter anytime soon. If the IAF feels that it needs one, to counter a threat from PLAAF with its J20 then we'll see. The IAF is very happy with its M2K. So if the AMCA can play the role that M2K has for the IAF in the next 2-3 decades they'll be happy.
Let's not forget that it won't just be fighters. ISR will move to dedicated platforms including ISTARS & UAVs apart from satellites. We could see a greater push towards the unmanned strike aircraft which could free up the amca from some of the strike roles. Currently it's not even in first gear. And a future off the shelf purchase of the Su57 itself may not be off the cards.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by Austin »

Indranil wrote:No other 5th generation program fits India's bill. The fallout in the case of FGFA was on workshare. India was not getting the research ROI on the RnD dollars.
Not really on workshare because FGFA was a JV along the line on Brahmos/MRSAM ( not a TOT program like MKI ) and HAL and IAF own Varthaman committe already cleared the program.

The issue was cost committing to FGFA in the number IAF wanted would mean spending $25-30 billion in cost over its life , IAF does not have the resources to commit that kind of money , Infact it does not even have the money to buy 126 Rafale and had to go with just 2 squadrons worth.

IAF has huge procurement backlog not just for fighter program but also for Transport , SAM , AD etc you name it and IAF has a long laundry list that is as important as buying a fighter as some of these system will be facing mass obsolence in less than decade time.

Having said that IAF may still buy few squadron of FGFA because replacing a Heavy fighter like Su-30 will be done by another of similar class and Indias own AMCA is a work in progress with no definative time line or even FSED started but that will happen only in many years from now.

Indian defence budget under BJP has shrunk as % of GDP and IN and IA also has its own program.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by nam »

My view is that IAF is not going to replace earlier Su30 with AMCA. It might replace it with MWF.

IAF has constantly declared, that it does not want more Su30 as it was a heavy burden on OPEX.

Overall 260 Su30, 36 Rafale i.e close to 300 heavy. It would make no sense to replace a OPEX heavy Su30 with another OPEX heavy 150 million AMCA!

With 8 sqd of AMCA, IAF can easily replace 40 Su30 with MWF.

Overall :
220 Su30+ 160 AMCA+ 36 Raf = 416 twin engine
200 MWF+ 40 MWF(Su30 replacement)+ 123 LCA MK1= 363 SE

Even with reduced Su30, IAF will still be twin engine heavy. If they want sqd numbers and control over OPEX, they need to increase MWF numbers.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by JayS »

What are the latest specs for AMCA...?
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by brar_w »

Prasad wrote: Currently it's not even in first gear. And a future off the shelf purchase of the Su57 itself may not be off the cards.
I think you are spot on. The "FGFA" that the IAF appears to have wanted is likely a decade out (once one factors in maturity and demonstrated operational performance). The farcical "Joint" effort in the program was not really leading anywhere. With close to a dozen prototypes, an Indian pilot had yet to even fly the aircraft and it does not appear that the IAF had access to 100% of the development or testing effort. So the MOD/IAF pursued the best course of action at the time and abandoned the joint development effort. They are likely taking a wait and see approach. If, come 2030, they like what they see, they may procure the aircraft OTS or develop it like they did with the MKI depending upon the status of the AMCA at the time, the health of the MKI fleet and the Super 30 upgrade program, and the threat perception at the time. If the AMCA goes well, they may skip it altogether and that was even echoed in the IAF Chief's latest comments.
Last edited by brar_w on 04 Nov 2019 00:44, edited 1 time in total.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by Ganesh_S »

Katare wrote:I have a totally different take on it, FGFA has been thrown out because IAF/GoI have finally grown a pair each to refuse friendly invitation from Russia to be it’s bitch or a guinea pig again. FGFA wasn’t the deal we needed or wanted.
Saar, was this required in this thread? Or even the context of the arguement.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by Cain Marko »

Austin wrote:
Indranil wrote:No other 5th generation program fits India's bill. The fallout in the case of FGFA was on workshare. India was not getting the research ROI on the RnD dollars.
Not really on workshare because FGFA was a JV along the line on Brahmos/MRSAM ( not a TOT program like MKI ) and HAL and IAF own Varthaman committe already cleared the program.

The issue was cost committing to FGFA in the number IAF wanted would mean spending $25-30 billion in cost over its life , IAF does not have the resources to commit that kind of money , Infact it does not even have the money to buy 126 Rafale and had to go with just 2 squadrons worth.

IAF has huge procurement backlog not just for fighter program but also for Transport , SAM , AD etc you name it and IAF has a long laundry list that is as important as buying a fighter as some of these system will be facing mass obsolence in less than decade time.

Having said that IAF may still buy few squadron of FGFA because replacing a Heavy fighter like Su-30 will be done by another of similar class and Indias own AMCA is a work in progress with no definative time line or even FSED started but that will happen only in many years from now.

Indian defence budget under BJP has shrunk as % of GDP and IN and IA also has its own program.
Some very good points Austin, the question is will the iaf replace the mki with another heavy or a medium. IMHO the flanker surely brings more strategic reach and hence the iaf will certainly not forego such a capability. Maybe not a one on one replacement but if expect a number of sqds of the fgfa. The bird has tremendous range/endurance allowing it to be a worthy successor to the MKI.

The AMCA was never meant to be an mki type heavy replacement. I'd expect it to come in numbers as a replacement for the fulcrums and mirages, possibly jags as well.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by Manish_Sharma »

^ carrying 6.5 tons of ordinance Both A2G and A2A + Carrying 7 tons of fuel with advanced fuel sipping engines AMCA can easily replace 8 ton Ordinance + 8 Ton fuel carrier Su 30 MKI
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by Cain Marko »

^ err...mki carries almost 10 tons fuel without mlu and EFTs. If you do the numbers carefully, you'll note that the 8 ton payload could be rather deceptive considering the mtow on the mki is greater then 38 tons quite unlike the lesser analogues sported by northern neighbors. And then there is the brahmos...

As a pure hauler, the mki is an absolute beast enabling the iaf with rather long reach. I don't see how any mid sized bird can do any better. And this is without the mlu.

The pakfa has even better credentials.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by Aditya_V »

I dont AMCA should try and Match the SU 30MKI payload with Medium Combat Aircraft engines and airframe, thats not doable
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by ashthor »

In the lines of LCA, LCA Mk.1A and MWF maybe they will go for a Heavyweight after AMCA is done with. AHWF
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by JayS »

brar_w wrote:Indranil, all great points and thanks for your insight. A few replies -
Indranil wrote:2. IAF is not thinking of AMCA as a replacement for an aircraft or set of aircrafts. Frankly, there are no airplanes in IAF's inventory which does AMCA's role, albeit stealthily. Rafale is just entering service and too few in numbers for AMCA to replace.

So the IAF will physically not replace any aircraft with the AMCA? What about the mission sets currently performed by the aircraft that will be retiring from service between 2030 and 2050?..Would the AMCA not be tasked with taking over those missions? Operational realities require an analysis of the capability you are trying to recapitalize and seeing how the incoming capability will take over - even though, the way it does that mission may be different. One could have envisioned a silver bullet 5GFA force (used like the F-117 for example) in the 2020's but if the AMCA is going into production and service for the post 2030 then it will need to proliferate into the IAF far deeper than that given how A2A and IADS capabilities of the primary opponents (China) is going to evolve over the next 30 years.
The existing fleet of medium jets, M2K, MiG29UPG and Jaguars will be replaced by MWF in numbers and mission capability. But I do not consider it to be a replacement of "Medium" capability (capability, not weight category**) of IAF, but rather it will be a new "Light" capability for IAF. IOW, IAF's bottom-line would be lifted up from MiG21/MiG27 to LCA-Mk1A/MWF. AMCA will bring in a new "Medium" capability to IAF, complimented by Rafale (complimented, because Rafale has limited 5th gen capabilities while AMCA will be a proper 5th Gen fighter. Going into 2040's AMCA will lead the category). Mission capability wise, there may be some overlap with the missions from current "medium" and "heavy" categories, but with added dimension of 5th Gen capabilities.

I think the answer to your point in the last line, is - UCAV. UCAVs will give the additional edge needed. Ghatak will come online sometime in 2030s. I would like IAF to go with a twin engine UCAV rather than spending resources on Su-57 any time in future.

IMO, need of heavy 5th Gen manned fighter is highly debatable. I personally think, its not a necessity for IAF, if they can make AMCA work satisfactorily. If someone thinks we need a heavy manned stealth fighter, I would like to hear the arguments other than "we need to replace Su-30MKI" which, IMO, itself is not a strict requirement. If someone has a cogent argument in terms of realistic mission profiles that IAF would need in 2035 onwards, but not covered by AMCA or a twin engine UCAV with equivalent weapons, then it would be interesting to hear.

brar_w wrote:
Indranil wrote: If there will be no FGFA, then AMCA will be taking on the role of air dominance. All indicators point in that direction. Even in the latest spec release, the focus has been on close "combat capability" and "supersonic persistence" citing high TWR. Clean TO is 20 tons and at 220 kN of thrust, the intended TWR at clean take of would be greater than 1.1. I think they will have supercruise with caveats, e.g. cannot supercruise with full internal fuel or punch through the Mach barrier using limited AB and then sustain on military power.
Of course you make do with what you have. But it will be difficult to replace "FGFA requirements" (assuming the IAF demanded a set of requirements from Russian side) with the AMCA. Of course, it will still do the mission but will have to do it differently. Even the F-22 and Su-57 will use AB to punch through the transonic range even though they can (eventually if not at baseline for the PAKFA) do so without it. You have to stay efficient and manage your fuel and zipping past the transonic region is going to get that.
I think the only issue with AMCA vis-à-vis FGFA would be that the strike package will need more nos, especially, dedicated A2A fighters in it for same kind of mission, due to its smaller and single bay (As you already know, AMCA is limited by the availability of powerplant, rather than SQR. The shortcoming could be circumvented by nos.). Question in my mind is, did IAF have an organic mission requirement prescribing PAKFA class fighter to start with, or was it an opportunistic decision to go with PAKFA and IAF came up with FGFA in sync with it post facto...? Given there is next to nothing authentic information available on this topic its difficult to draw conclusions on it.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by JayS »

Indranil wrote:
JayS wrote:The argument that 5th generation requirements enforce suboptimal aerodynamics is a 4th Gen vs 5th Gen aircraft comparison. Question is if for identical requirement, if one designs a 4th gen aircraft and one 5th Gen aircraft, for same combat configurations which one will have lesser drag.? Do you think they will be equally good..??
Define the mission and I can give a better answer. For example, if it is long air patrols, a fifth gen fighter with more internal fuel and internal A2A missiles is likely to have lower drag. Similarly, if the strike distance is high and the strike package is small, the fifth generation fighter has lower drag.

You will accuse me of moving the goalposts to the sweet spot of the 5th generation fighters. Okay, so let us put the goalposts at the sweet spot of the 4th generation aircraft. Let's choose missions that 4th generation fighters can complete on internal fuel only. For these roles, the fifth generation aircraft has more drag than the 4th gen counterpart because it pays the price of higher internal volume and hence empty weight. But that doesn't mean that the 5th generation fighter has to compromise on maueverability or too speed. 5th generation aircraft have higher TWR, a luxury that F35 did not have, thanks to its one engine design. PAKFA has more internal volume in both its fuel tanks and bomb bays. It did not compromise on maneuverability neither on top speed (albeit it has moving intakes). AFAIK, the SQR for AMCA does not allow any compromise for these either.

It is about design goals and constraints. F35 was designed with the constraints of a single engine and goal to complement the F22s. That's not the constraints and goals of other countries.
One cannot decouple problem like this - having same internal fuel for 4th Gen fighter as the 5th gen fighter for same mission profile. Going by practical experience, you would end up designing a smaller 4th Gen fighter for same mission considering EFT, because you do not really care about the RCS. And the stealth requirement does not enforce you to go with features like S-duct, rectangular exhaust etc which in turn forces you to have bigger engine and drive the size of the fighter upwards.

Higher drag or larger size does not mean lack of maneuverability. Performance and maneuverability is dictated by Wing Loading and TWR, as you would know. If you meet the required W/S and TWR, any size or shape of aircraft could be equally manoeuverable.


If we have 4th Gen fighter A with same internal fuel and for simplicity, same mission empty weight, as a 5th Gen fighter, then for same weapons load, we have same total mission weight. Induced drag could be assumed to be same for both then. Plus difference between the profile drag can be ignored as it would be very small.

What we remain with is wave drag and interference drag. its difficult to argue without numbers on heavy configurations. We may be able to draw some conclusions on A2A configurations, but then we will not have data to verify them with.

My points earlier were not specifically for F35. There is a generic penalty to be paid for 5th generational characteristics, in terms of wave drag. please see the quote I posed by the F35 program Director. This links to the Sears-Haack body. If the jet can be elongated for better fineness ratio the wave drag penalty could be reduced for the same internal volume but then you would end up with higher empty weight and the creep associated with it, in best case. In worse case, it may not be possible practically speaking.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by Indranil »

I think you and me are now saying the same thing. AMCA designers may choose to design the aircraft with higher fineness ratio. Yes, that will come with compromises especially in the stealth strike role. But I can't see IAF compromising with the air dominance role.

The latest specs are what was released at defexpo 18. You can see that the span and height of the AMCA is slightly smaller than F35A, but the length is 10% higher.

I have little problem with accepting the empty weight with those numbers. 12 tons is going to be tough.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by JayS »

Those specs from Defexpo 18, indicate that the internal fuel would be limited to 6T max in best case scenario (20T - 12T - 0.5T - 1.5T).

The Super Hornet is bigger than AMCA and manages in 14.5T empty weight. Given the smaller size and more composites, 12T seems doable. May be 12.5T worst case.

AMCA's combat range and radius should be at par with, if not better than that for the Super Hornet, given same power plant, slightly smaller weight with slightly less internal fuel.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by Cain Marko »

JayS wrote:[
IMO, need of heavy 5th Gen manned fighter is highly debatable. I personally think, its not a necessity for IAF, if they can make AMCA work satisfactorily. If someone thinks we need a heavy manned stealth fighter, I would like to hear the arguments other than "we need to replace Su-30MKI" which, IMO, itself is not a strict requirement. If someone has a cogent argument in terms of realistic mission profiles that IAF would need in 2035 onwards, but not covered by AMCA or a twin engine UCAV with equivalent weapons, then it would be interesting to hear.
.
Iirc MKIs often tasked with ultra long ranged missions starting from Pune to A&N and back refueling at least once. This could be on air patrol or some other type of mission which we can at best speculate.

Can the AMCA perform such missions considering it's a pretty small platform? Can the ghatak perform air to air missions or self escort if required at such long ranges? Somehow I doubt that a manned 5gen mission will be discarded any time soon. Iaf may even need such a platform in 2030 to supplement the MKI. Perhaps as escort or even as openers...
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by JayS »

^^ We will have a good number of Super 30 lasting into 2050s. Only a couple of sq are sufficient for such missions which will be needed rarely, it at all.

Where are we going to send them for Air patrol over such long range...? Nobody does air patrol over thousands of kms out from home base. It has to be a strike mission or an escort to such strike package.

The debate is not over "manned 5th Gen mission", but "need of 5th Gen heavy manned fighter" for India.

The current Ghatak is small one. Its possible to make a twin engine UCAV for long range strike mission. Self escorting/A2A on strike missions would not be a big deal for AI/ML 20-30yrs out in future. A lot of building blocks are available even today. As such they will likely be monitored by manned systems. Like from manned fighters at stand off distance or from home base using SAT links with possible human intervention for key decisions.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by VikramA »

Saurav Jha just wrote a nice acticle about AMCA. link:
http://delhidefencereview.com/2019/11/1 ... elopments/

points: 1 AMCA TD will fly in 24-25
2 AMCA MK 1 will fly in 29-30 and will have diverterless supersonic inlets (DSIs), GE 414 engine, will not have super cruise.
3 AMCA MK 2 could be flown pilotless and will have 110 kn engine and super cruise
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by sankum »

Informative article by S jha.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by JayS »

25T MTOW. 6.5T internal fuel.

Full spectrum TDs. DSI fixed.

Likely HAL lead consortium manufacturing AMCA.

Many other interesting things.

But don't take them as things set in stone. Thinks will remain fluid for next 4-5 yrs.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by Karan M »

The engine issue is the biggest challenge. I hope we induct several squadrons of AMCA Mk1 w/basic Ge414INS6 itself for stealth strikes. The definitive Mk2 can come later.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by VikramA »

With 6.5 ton fuel what kind of combat radius are we talking about here in air superiority role?
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by brar_w »

^^ Would depend upon what the payload required is for the Air Superiority missions. It should be quite decent if you're looking at a 4 Missile payload and have all internal sensors (i.e. no pods). Could match or exceed something like an LCA with a couple of bags and a similar weapons load. But if the IAF demands 8 or so missiles (6-8 missiles has historically been the preferred load out for Air Superiority focused 5GFA's) then the aircraft will look different and they may have to trade some range/radius for a more optimized IWB.
Last edited by brar_w on 13 Nov 2019 00:57, edited 1 time in total.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by sankum »

Indranil said the range radius at 600NM that is 1100 Km for 20 ton clean stealthy mission on internal fuel.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by brar_w »

sankum wrote:Indranil said the range radius at 600NM that is 1100 Km for 20 ton clean stealthy mission on internal fuel.
I think that will also depend upon what roles the IAF assigns Indranil also hinted at the AMCA taking over the role of air dominance within the IAF, and it being increasingly important if the PAKFA/FGFA does not happen. If that is the case, would the current IWB set up for the TD's survive the final decision (has the design been frozen?). From the picture in the SJHA article, it seems that the IWB is, much like the F-35, designed around a self-escort strike mission with a couple of bombs and a couple of missiles. Can they squeeze in 6 BVR missiles in there? And what does the IAF think is an optimal BVR/CCM mix for a future air-superiority fighter? I think these are important variables before attributing combat radius because things could look differently if the IAF decides it wants to value certain things more than others.
JayS wrote:
But don't take them as things set in stone. Thinks will remain fluid for next 4-5 yrs.
I think that is reasonable. Things are likely to change as the TD are developed and as the IAF evaluates them and sees what it needs to add or remove..
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by Indranil »

Bhai, Indranil is just an observer. Take what he says with a huge bag of salt 8)

By the way, what a great article by Saurav. Clean, with new information and without judgements. When I was growing up, parents used to ask kids to read the newspaper to learn the language and know what is happening. Today, I would try to keep my son away from the opinion moulding that happens in the name of journalism these days.

AMCA is being designed to IAF's requirement specification based on roles that they do today. So range and capability of the aircraft is tailored to that. The support for the iterative development of AMCA is so heartening to see. AMCA Mk1 will not have supercruise, but Mk2 will. This tells you what IAF is thinking.

Saurav has let a few cats out of the bag:
1. AMCA will have DSIs. Will MWF have it too?
2. Specfications of Ghatak. A 13 ton UAV is a serious deal.
3. Navy is asking ADA for a twin-engined fighter even before Naval AMCA.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by Prasad »

DSI work was done for AMCA only I think. Mk1 will be/is seen as a step up from the MWF and a natural progression towards the eventual Mk2.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by nam »

Indranil wrote:3. Navy is asking ADA for a twin-engined fighter even before Naval AMCA.
If this is approved, it will be a desi Rafale. IAF will be tempted to replace some of the older Su30 with a twin engine version of MWF!

Will hit the twin versus single pilot & availability sweet spot which has been the issues with Su30.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by sankum »

https://www.ainonline.com/aviation-news ... arrier?amp
The construction of the IAC-2 will take between seven and 10 years. “We see it starting within a three-year period,” noted Lanba, adding, “We are also hopeful for a new fighter produced in India [for the IAC-2]. This will move progressively from the LCA Navy to a twin-engine deck-based fighter.” He confirmed that this project is unrelated to the Advanced Medium Combat Aircraft (AMCA) program.
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Re: Advanced Medium Combat Aircraft: News & Discussion - 30 August 2019

Post by Cybaru »

I think the MTOW will be closer to what it is for FA-18G that is approximately around 30 tons. Designing something around 25 tons and then adding bigger engines doesn't make sense.

If they ensure that AMCA can carry 8-10 tons of fuel and only 2 tons of internal bombs, the need for heavyweight category almost diminishes. It might require two AMCA to do the job of one AHeavyCA (AHCA), but we won't need two different types.

IMO, the internal fuel is going to be the key for further requirements. Even if it is a pig at take-off and reaches better/ideal operating capabilities after burning away 2-3 tons of fuel, by the time it reaches enemy airspace, that is the approach we should take. Look at the Rafale interview - All aircraft in bomb truck mode suffer.
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