AMCA - Advanced Medium Combat Aircraft

Spitfire IX said:

IAF lacks a 5G fighter. 3 countries make them. Buying from China is out of the question, which leaves US and Russia as possible suppliers. For political reasons operating F-35 is much riskier than Su-57, so why not buy Su-57? As you say, it takes the pressure off getting AMCA developed and into production ASAP.

I note, however, that 4 years after receiving its first Su-75 the Russian air force has a very small number (less than 20?) which makes me wonder how fast they can be made.

If F-35 and Su-75 are too risky, there is always KF-21 to plug the gap for India until AMCA arrives. It is not expensive but probably better than Rafale, Eurofighter etc.

Click to expand...

Su 57 or 75 ?
Su75 is so far from being operational..... Better put a bet on AMCA.
Su57 will be costly, and with the loss in Ukraine I think Russia not ready to divert production from its own market.

BON PLAN said:

Su 57 or 75 ?
Su75 is so far from being operational..... Better put a bet on AMCA.
Su57 will be costly, and with the loss in Ukraine I think Russia not ready to divert production from its own market.

Click to expand...

Su-75 is a concept. Sukhoi does not seem to be able to come up with a design that potential buyers find appealing. It may never be launched.

Just a thought - why not consider buying 3 squadrons of KF-21 or F-15EX as an insurance? Can't get Rafales for a long time. Can't be sure if MMRCA 2.0 will happen or when deliveries would start. Can't be sure when AMCA deliveries would start. Can't be sure of Su-57 delivery rate or when.

Otherwise wait for Tejas Mk2 and make do with that until AMCA arrives.

Bhartiya Sainik said:

Not a good idea bcoz while moving it is occupying space of IWB in lower corners of IWB & will strike the fins of weapons.

If we trace the locus of the door then it looks similar to that of a stick or ladder sliding down :
View attachment 2019

If we imagine this locus superimposed on IWB shown by ADA then it is clearly not feasible.
View attachment 2025

Not even with folding fin weapons.

Not just that, even if the IWB door width is reduced half resulting in 4 doors total, imagine the tandem IWBs of Su-57 in parallel, then also the doors opening internally will strike the weapons.
I am using edited Su-75 cross-section to depict the scenario :
View attachment 2040
NOTE - the circular cross-section weapon above is not the current BVR-AAM like Astr, Meteor but bigger diameter weapon with folding fin, A-A or A-G.

Better solution would be to have these doors open outwards like in Su-57.
View attachment 2043

Click to expand...

BTW, AMCA MK1A, FOC AMCA, whatever people wan't to call it, the production jet needs to have re-engineered 6 BVR-AAMs with folding fins to deliver economical firepower per sortie during war & not just be a peace-time patrol jet. If beyond 4 BVR-AAMs not possible then at least 2 CCMs should be added.


1st few AMCA prototypes would probably be TD (Tech Demonstrator) like in case of LCA-TDs which cannot be compared to LCA-MK1 inducted jet. Such was the diff. b/w X-35 & F-35; YF-22 & F/A-22. FC-31 specs towards J-35 already increased.
Make corrections where required. I'm giving a "low IQ" refresher.
CTOL F-35A's stealth config weight 13.3T empty + 8.3T fuel + 6 AIM-120 (6x152=912 Kg)= 22.5 tons.
Afterburner takeoff T/W = 191.3 KN / 22.5 T = 191.3/9.8 /22.5T = 0.86



R&D going on for short missiles like MSDM, AIM-160 CUDA/SACM & Peregine, and longer range ones like AIM-260 JATM, Long-Range Engagement Weapon (LREW).



FC-31V1 flew 1st, then V2 then V3/J-35. Weight & other parameters increased. V1-31001 was just TD. J-35 makers have intentions to have 6 PL-15 AAMs, may be shorter CCM also.
PL-15 - 200-250 Kg, 13'4" long, 20cm diameter, 200-300 Km range, Mach 4+
J-31 is AF version, rumored to have recently flown 1st, whose empty weight is not known. Different sources claim WS-19 engine to have 98-124.7 KN wet thrust. And videos & photos depict J-31/35 to have 6 PL-15 AAMs eventually with possibly CCMs in SWB also.



KF-21 Boramae also with F414 engines, empty weight 11.8T + 6T fuel + 4 AIM-120 (4x152=608 Kg) + future IWB 1.3 tons = 19.7 tons.
Afterburner T/W = (2x97.9 KN) / 19,7 T = 195.8/9.8 /19.7T = 1.01

FOC AMCA should try to fit in staggered 6 BVR-AAMs.
Meteor - 190 Kg, 12 ft. long, 18cm diameter, 200 km range, NEZ 60Km, Mach 4
Astr MK3 SFDR - 220 Kg, 12'8" long, 20cm diameter, 60cm wingpan, 350 Km range@20Km altitude, 190Km@8Km altitude, Mach 2-3.6 interception
MICA-IR weighs 112 Kg & 10' long, AIM-9 weighs 86 Kg * 10' long, ASRAAM & IRIT-T weigh 88 Kg & 9.5' long, PL-10 weighs 105 Kg & 10' long.
If DRDO can make 5'5" long missile like SACM/CUDA then FOC AMCA can go for SWB. IWB can also carry 4 BVR-AAMs + 4 half-CCMs.
Now AMCA's ESTIMATED empty weight 12T + 6.5T fuel + 6 BVR-AAMs (6x220=1320 Kg) = 19.8 T, rounded up to 20 T with 2 SWB-CCMs.
Afterburner T/W = (2x110 KN)/ 20 T = 220/9.8 /20 = 1.12 with new engine.
(2x98 KN)/ 20T = 196/9.8 /20 = 1 with F414 engine.

------------------------------------------------------------------------------------------------
Some people asked if AMCA will carry AShM , CrM, ARM INTERNALLY

The picture above itself tells everything that AHCA will be required. I cannot imagine AMCA or any 5th gen medium jet, not even J-31/35, with fuselage identical to F-22, to have 19-20 feet long IWB carrying (18' long 600Kg) missiles with 2x98-110KN engines, at least not the present Rudram-1 - 600 Kg, 18' long, 32cm diameter, 95-100cm wingspan, 150 Km range.

62' long F-22 can carry only 12' long AIM-120, AMCA fuselage is identical to F-22's.
65' long Su-57's IWB is 14.4' long. The 2 tandem IWBs are not joined otherwise it could have carried Novator & some ARM, AShM, cruise missiles.
Neither of them expanded their IWB for ARM, AShM.
For 58' long AMCA to carry 18' long AGM in IWB, the depth/height of IWB will also increase affecting the arrangement of other components changing the shape of fuselage, wings, a new jet basically.

Something like AM-88G AARGM-ER - 361 Kg, 14' long, 25cm diameter, 110cm wingspan, 300 Km range, which will be shortened further i guess, can be imagined.



ADA has said that internal load is 1.5 tons with 98 KN wet thrust. If 110 KN engine is developed for FOC AMCA then in same T/W ratio IWB capacity will be 1.68 tons, divideby 4 = 421 Kg. So Rudram length will also have to reduce by roughly 2/3rd to 12 ft, or diameter can be reduced & length can be increased.

Now for the lateral dimensions, let's consider Astr MK3 SFDR with 20cm dia. & folding wings like shown above in diagram. With 5cm lateral clearance on both sides, missile will occupy 30cm width. For 3 AAMs 90cm width IWB is required.
For 2 Rudrams in each L+R IWB 90/2=45cm width will be available which will suffice for 32cm dia. Rudram with folded fins keeping 6.5cm lateral clearance on both sides.

Spitfire IX said:

Su-75 is a concept. Sukhoi does not seem to be able to come up with a design that potential buyers find appealing. It may never be launched.

Just a thought - why not consider buying 3 squadrons of KF-21 or F-15EX as an insurance? Can't get Rafales for a long time. Can't be sure if MMRCA 2.0 will happen or when deliveries would start. Can't be sure when AMCA deliveries would start. Can't be sure of Su-57 delivery rate or when.

Otherwise wait for Tejas Mk2 and make do with that until AMCA arrives.

Click to expand...

KF21 is not ready. The combat system is only at a very early stage. 5 years minimum before having a bird with only (limited?) air to air capacity.
F15EX is a solution, but what about the same league Su 30? It's more interesting to built some more (already assembled by HAL) and adding a strong MLU. I add that the production schedule of F15EX is low... so few long lead time components ordered.
Why not some mor Rafale ? It is already tailored for Indian use, and the ramp up of the production in on track. A minimum of 3 birds a months is intended for mid 2025. Dassault has plan to go further, probably thanks to a indian assembly line in case of.

Bhartiya Sainik said:

Your statement is correct w.r.t. engines made in same era/generation with similar dimensions, weight, volume, materials, architecture & guidelines. It becomes easy to analyze an engine upcoming soon.
But my focus is on technology as a whole, be it any engine. I want to understand what makes a perfect jet fighter engine. Theoretically given fixed inlet diameter & body length, how much max dry thrust can be achieved? Is there any ideal permutation combination of parameters which can be replicated to any size of engine of light/medium/heavy fighter jet?

You did not address this point on weight-

- All GTE makers DON'T have access to R&Ded composite materials to reduce weight & products like single-crystal blades/blisks, film cooling, ceramic stealth, etc, some of which increases weight.

- What about inlet diameter which governs air mass flow, along with air density, altitude & velocity? Higher diameter means lesser RPM bcoz blade-tip cannot cross Mach-1 .
- What about compression/pressure ratio?
- What about # of fan, compressor & turbine stages which affect compression & weight?
- What about engine length? Is there any ideal aspect ratio b/w inlet dia. & engine length?
Are there any metrics for the above parameters?

IDK what should be ideal Turbine Inlet Temp. for jet fighter engines but in my homework excel sheet I observed range is 1,200 C / 1,470 K in Yak-130 & JL-10 to 1,980 C / 2,260 K in F-135.
What creates this difference? Fuel type? Combuster design? Compression/Pressure ratio? Fuel-Air mix ratio?
IDK what thrust difference will be created by 50-100 C Tu.In.Te. difference.

Dry & Wet thrust capabilities are different. Every engine has different extra Wet %. So i think we should study them separately.
I have manipulated the values in ratio to bring them closer in a Graph to compare them closely.

View attachment 1925
View attachment 1915
We see that -
> Turbine inlet temp. is a very low slope line. It takes a dip with EJ-200.
> Inlet diameter, inlet area, engine weight, volume, air mass flow show identical increasing trend.
> But, Engine length, dry thrust, dry T/W ratio, dry T/Vol ratio, Bypass ratio take a dip with F414.
So the big dip in Bypass ratio might have impacted dry thrust & then dry T/W ratio, dry T/Vol. ratio. I wonder if engine length also influenced it.
> # of compressor & turbine stages take a dip with EJ-200. This could have affected compression ratio also.
> F119's # length, inlet dia/area, body volume, weight, air mass flow jumps obviously.
But # of stages, compression ratio, fuel SFC, take a BIG dip but impacting its dry T/W & T/Vol ratios
STILL its dry thrust is like DOUBLE.


I respect your PoV, I also agree that very similar engines can be compared like that & people should not say bluntly "we need 110KN wet thrust class engine for AMCA" bcoz no jet will fly on wet thrust for long & like i said.




Whoa! It is not that easy. A whole IT consulting industry thrives on doing such comparisons. In short it depends on application type - household/commercial, span - LAN/MAN/WAN;; speed - real-time, archiving, etc; H/w required - handheld device, Laptop/Desktop, server, Mainframe, Supercomputing; etc. But there are lot many other things, out of this forum's scope.

Click to expand...

Brother I dont won't to offend you and I respect your dedication but people neither have time nor the technical expertise to understand everything thing that you write.

To understand working and design of jet engine
1)first start with brayton cycle
2) understand both temperature-entropy diagram and pressure-volume diagram.
Use any good thermodynamics book like thermodynamics by yunus ali cengel.
3)learn basics of heat and mass transfer.
3)after understanding that,
learn the design of engine from cohen and Roger book.

We should also understand the difference between design and engineering.

Ideally the best engine should have infitely high TET, infinite compression ratio, 100% efficiency, infinite mass flow rate and should have only one compression stage and one expansion stage.

And I, can design a thoretical engine with the above parameters but just because i can design it doesn't mean engineers can manufacture it. Most limits are set by material limits, thermodynamics laws and laws of fluid mechanics. No material have infinite toughness and infinite creep resistance.


I will write a detailed article about how engines are designed in future. The procedure is quite similar to other turbo machinery. It will take a lot of time but it will help solve engine related doubts of many people.

BON PLAN said:

KF21 is not ready. The combat system is only at a very early stage. 5 years minimum before having a bird with only (limited?) air to air capacity.
F15EX is a solution, but what about the same league Su 30? It's more interesting to built some more (already assembled by HAL) and adding a strong MLU. I add that the production schedule of F15EX is low... so few long lead time components ordered.
Why not some mor Rafale ? It is already tailored for Indian use, and the ramp up of the production in on track. A minimum of 3 birds a months is intended for mid 2025. Dassault has plan to go further, probably thanks to a indian assembly line in case of.

Click to expand...

Sure, get more Rafale, if possible. I think you are right - better to buy more Su-30 than F-15EX.

In the meantime, Indonesia pulled away from buying M2K from Qatar, so India can buy them if it wants to. What does it matter if India thinks they are overpriced? It is worth paying extra if you are acutely sort of fighters. Better than shuffling around in circles in confusion which results in no more fighters.

HAL has just switched Nashik to Mk1A assembly, has it not? That is where Su-30MKI are assembled, I believe.

By the way, Meteor, Iris-T have already been tested with live firings on KF-21 while I think that AMRAAM and Sidewinder are being integrated. I believe that all should be integrated by the time the air force receives its first KF-21 scheduled for delivery in 2026. Perhaps ASRAAM, too.

scholar of war said:

Brother I dont won't to offend you and I respect your dedication

Click to expand...

This is an international arena. None of us have the right to offend, stop, discourage eachother for any reason if our actions don't violate any rule.
People on forums can be from high school kids to retired people. So there is nothing to get offended or to offend others. "Honesty is the best policy".

scholar of war said:

but people neither have time nor the technical expertise to understand everything thing that you write.

Click to expand...

We are not others' representatives.
All i share are some diagrams, pics, some basic calculations.
People who don't comprehend something should ignore & move on, simple. The Kaveri engine thread has mentioned MTech & PhD level stuff, i simply gave a like, that's all. Otherwise tell the admin to delete anything beyond Middle school level. - all Hi-Fi terminologies, R&D pics, diagrams, graphs, CFD by DRDO, HAL, ADA, ISRO, BARC, BHEL, etc, etc.

Again i'm introducing myself - In terms of PCM based subject grades, i was among the back-rankers in last 25% of class.:kyle: I already told u that i hated PCM My profile icon also says "low IQ".

scholar of war said:

To understand working and design of jet engine
1)first start with brayton cycle
2) understand both temperature-entropy diagram and pressure-volume diagram.
Use any good thermodynamics book like thermodynamics by yunus ali cengel.
3)learn basics of heat and mass transfer.
3)after understanding that,
learn the design of engine from cohen and Roger book.

We should also understand the difference between design and engineering.

Ideally the best engine should have infitely high TET, infinite compression ratio, 100% efficiency, infinite mass flow rate and should have only one compression stage and one expansion stage.

And I, can design a thoretical engine with the above parameters but just because i can design it doesn't mean engineers can manufacture it. Most limits are set by material limits, thermodynamics laws and laws of fluid mechanics. No material have infinite toughness and infinite creep resistance.

I will write a detailed article about how engines are designed in future. The procedure is quite similar to other turbo machinery. It will take a lot of time but it will help solve engine related doubts of many people.

Click to expand...

Now this is an expected reply. This website is global but don't worry about all visitors & members when you simply can't. Just write your stuff your way. Even if it bounces people's head, some of them will appreciate you & give a like.
I said i hated PCM but i will try to learn things you mentioned EXCLUDING MATHS.
GRAPHS help a lot. A picture is worth a 1000 words.
I'm not going to buy any book offline or online, but i am doing intense internet search since my college days in 2000s.
Thanks & regards for the expected part of reply.

scholar of war said:

Brother I dont won't to offend you and I respect your dedication but people neither have time nor the technical expertise to understand everything thing that you write.

Click to expand...

some like me would have sire we are in a professional defence forum where there can be school going kids to comedians and scientists too there is a scope for everyone to learn ask questions call out bs too sometimes
btw im a bio student but with immence will to know more bout defence tech this is what keeps me running back and back into the old dfi too to get references cross check facts and understand more doesnt it helps in my studies maybe it could but is getting knowledge bad i dont think so

Bhartiya Sainik said:

One of my college senior worked on LCA project in 2000s. He said that just like there was a tail-less delta wing concept of MCA, similarly there was of HCA too. The following image on internet then was of MCA:
View attachment 1932
But engine problem, lack of funding & internal disagreements were there. some techies in there said to use Su-30's engine, others criticized stating its poor quality compared to western engines. These are internal things which come out unofficially if we know someone inside, but may not be acknowledged officially.


Correct. Either by GTRE, JV or import we must get a heavy class engine to support AHCA or we are going to see HRCA/HRFA tenders by 2040.
For the record F-22 was inducted in 2005 but if we see a brief timeline:
Jan 26, 1973 1st formal ATF requirements document issued
may 21, 1981 formal request for info issued to 9 companies
Nov 28, 1981 approval given to ATF program
Oct 31, 1986 construction begins of YF-22
Aug 29, 1990 rollout of 1st YF-22 prototype & its flight
Sep 7, 1997 1st flight of 4001 spirit of Americe, 1st Raptor
Nov 15, 2000 4004, 1st flight of avionics test bed a/c
jan 5, 2001 4005, 1st combat capable F-22
Sep 29, 2003 1st F-22 delivered to 43 FS, Tyndall AFB
Dec 15, 2005 IOC declared

One person might say that it took 30 years from requirement document to 1st IOC jet.
Another person might say something else.
But today in era of advanced manufacting & materials compared to 1970s & 80s it doesn't have to take 30 years. But the requirement started unofficially since days of LCA & gained momentum when Su30K were inducted in Lohegaon AFB, Pune.


USA leads the R&D & it doesn't care if world agrees to version/generation #. Others can have their own interpretation, if they can manufacture or not. Same thing with MS Windiws 11, Apple iPhone 15 Pro, Samsung Galxy S-24 Ultra, Intel 13/14 gen Core i9, AMD Zen-5 Ryzen 9000, etc.
A Fighter jet gen leap occurs when as per new advancements a possible requirement is put up for which any current airframe won't suffice, simple.
5th gen's 1st priority prime feature are stealth & sensor fusion.
NOTE - I know F-35 is criticized due to lack of persistent supercruise, low agility, stealth coatings issues, less internal payload, etc but we sould not forget that it is a JSF for export hence it is intentional blunder, unlike F-22 ATF with export ban to closest allies also. Some issues will be ixed like supercruise with new ECU (Engine Core Upgrade). NGAD, F/A-XX, GCAP, FCAS will also most likely have export bans.
So 1 domestic product (F-22) qualified well,
another export product (F-35) failed,
but that doesn't change pace of technology evolution, standards.


As per USA's notional depiction & R&D, i estimate everything will be minimum 30-40% more.
Everything means - airframe size/volume,weight/range/MTOW, engine parameters, payload, weapons range, computing power, electricity.
Eventually a single-engine version will be made, that's natural evolution, which will be more in everything than F-35.


A laser pod can be put on 4th gen jet, helicopter, ground vehicle. it won't make F-16 as 5.5 gen.
View attachment 1940

View attachment 1941


For pure capitalist western nations everything is expensive, not for communist & socialist mixed economies. In beginnng everything is expensive, decade after decade, prices normalize.


Yes it is possible to counter export versions of J-31/35, Kaan, KF-21 Boramae, but we are already behind by 5-10 years. So majority of market will already be eaten by the time an AMCA-Ex appears, unless any nation wants to put in their money in AMCA funding.


As workaround we will develop AHCA with 4 engines

View attachment 1948
:kyle::stan:


Well, I hope you all enjoyed some LOL moment.
It takes time for a new generation of humans to educate, get experience, do R&D & produce something. If ISRO can flourish then we can expect our scientists & engineers with MTech. & PhD degrees to develop variable cycle engine, although quite late, may be in 40-50 years from now in 2060s-70s when i will be dead most probably, but they will, it is natural & inevitable.

Click to expand...

Finally a sensible post to knock some sense into the day dreamers here

View: https://x.com/alpha_defense/status/1810603847859249528?s=19

Agenda - supercruise
Can AMCA SUPERCRUISE with F414?
SHOULD AMCA supercruise withF414?
What kind of questions are these?

Supercruising is not about just squeezing out thrust from engines but also requires aerodynamic shaping of jets, good lift by wings &/or lifting body, variable cycle engine, inlet geometry control, pressure recovery & air flow management, etc.
NOTE - Afterburner thrust & MTOW are not required to consider. 50-70% fuel & std. A-A load is used.

Benefits of Supercruise -
- Higher launch altitude & velocity gives higher weapon range & NEZ (No Escape Zone)

- Supercruising jet has better chances to conceal IR signature compared to afterburner using jet.
- Evade incoming missile

But aircrafts also have to overcome air-friction & sonic drag forces.
At transonic speeds the sonic drag increases suddenly & sharply then falls towards Mach 2.

So ideally an aircraft should supercruise beyond Mach 1.8 at least. The danger zone is 0.9 to 1.5

Also, there is the "Whitcomb Area Rule" to shape a fuselage of jet to reduce the drag. Supersonic Area rue also there as per which the aircraft body need to be within the Sonic-Cone. These rules are being used in almost all jets i think. there could be more rules which we civilians enthusiasts may nor know yet.

Given any engine with an inlet diameter, it is upto designer how much thrust can be squeezed out. Engineers either do not know that limit or it is above top secret.
We already saw in previous posts the parameters required for airframe & engine performace.

2 same jets with different wing & fuselage design but with same # & type of engine(s) will have different performance.

Different sources give different data on Supercruise
For example F-22,

Fuel consumption is measured in units like g/KN/s or lb/lbf/hr, called SFC or Specific Fuel Consumption.

F-22's F119 engine's SFC with inlet dia. 100cm at 100% power (116-120.3 KN) is around 17 g/KN/s.
2 engines, so F-22 SFC is 34 g/KN/s at 100% power & Sup.Cr. Mach 1.5-1.8 (514.5-617.4 m/s).
So 3.94-4Kg/s fuel for covering 514.5-617.4 m/s or 128.6-156.7 m/Kg or 6.38-7.77 gm/m.
Empty weight 19.7 T + 50% fuel 4.1 T + full IWB 8 AAMs 1.1 T = 24.9 tons
Airframe T/W ratio at 100% power = 2x(116 to 120.3)/9.8 /24.9 = 0.94 to 0.98
Fuel per ton = (3,940-4,000)/24.9 = 158.23-160.64 gm/s/T.
50% fuel 4.1 tons while supercruise will be depleted in 1,025-1040 seconds or 17-18 minutes covering 527-642 Kms.

F-35's F-135 engines SFC with inlet dia. 109cm at 100% power (128.1 KN.) is around 20.3 g/KN/s.
Sup.Cr. M1.2 (411.6 m/s).
So 2.6 Kg/s fuel for covering 411.6m.s or 158.3 m/Kg or 6.31 gm/m.
But to go this extra 30m/Kg-fuel Vs F-22, the SFC is increased from 17 to 20.3 g/KN/s.
F-35A Empty weight 13.3 T + 50% fuel 4.15 T + 4 AAMs 0.6 T = 18.05 tons
Airframe T/W ratio at 100% power = 128.1/9.8 /18.05 = 0.72
Fuel per ton = 2,600/18.05 = 144.04 gm/s/T.
50% fuel 4.15 tons while supercruise will be depleted in 1,596 seconds or 26.6 minutes covering 675 Kms.
So we see that F135 engine has more thrust but higher SFC than F119 engine,
& F-35 goes further /Kg fuel, consumes less fuel per unit distance, per ton of body BUT has lower T/W ratio and cannot supercruise.

GE F-414 engine's SFC with inlet dia. 79cm at 100% power (57.8-61.83 KN) is 20.5-23.25 g/KN/s depending upon model. 75 KN JV engine is planned.
2 engines, so AMCA SFC will be 41-46.5 g/KN/s at 100% power.
So 2.37-2.87Kg/s fuel will be used.
AMCA empty weight 12 T + 50% fuel 3.25 T + 4 Astr MK3 SFDR 0.88 T = 16.13 tons
T/W ratio at 100% power = 2x58/9.8 /16.13 = 0.73
Fuel per ton = (2,370-2,870)/16.13 = 146.93-177.92 gm/s/T.
let's assume that with 0.73 T/W AMCA can also supercruise at M 1.2 (411.6 m/s).
50% fuel 3.25 tons while on supercuise will be depleted in 1,132-1,371 seconds or 18-23 minutes covering 466-564 Kms.
When new engine with 75 KN dry thrust will be available then hopefully 6 AAMs will be carried.
T/W ratio at 100% power = 2x75/9.8 / (16.13 + 0.44) = 0.92
Then hopefully AMCA will supercruise around M 1.5

NOTE - Among these 3 engines F414 is smallest engine with highest SFC at 100% power.
NOTE - IDK what is the SFC of these engines at say Mach 0.7 & what is the throttle position. I think these kind of parameters are secret. Sometimes these fiigures are calculated at full IWB load, sometimes AA load + 50%-80% fuel dpending upon fuel left after reaching 35-40K feet altitude & supercruise speed.

Rafale's M-88-2 engine's SFC with inlet dia. 70cm at 100% power (50KN) is 22.14 g/KN/s.
2 engines, so Rafale SFC is 44.28 g/KN/s at 100% power & Sup.Cr. Mach 1.4 (480.2 m/s).
So 2.21 Kg/s fuel for covering 480.2 m/s or 217.28 m/Kg or 4.6 gm/m.
To go this extra 59 m/Kg-fuel Vs F-35, the SFC is increased from 20.3 to 22.14 g/KN/s.

EF-2000's EJ-200 engine's SFC with inlet dia. 74cm at 100% power (60 KN) is 21-23 g/KN/s.
2 engines so EF-2000 SFC is 42-46 g/N/s at 100% power & Sup.Cr. Mach 1.5 (514.5 m/s).
so 2.52-2.76 Kg/s fuel for covering 514.5 m/s or 186.41-204.16 m/Kg or 4.9-5.36 gm/m.

So we see that Rafale with empty design weight 8.5 T, 492 sqft clipped delta wing & 50KN engine can supercruise at M 1.4
but F-18E/F with empty design weight 14.5 T, 500 sqft. trapezoidal wing & 58 KN engine cannot due to 6T weight increase due to carrier-ops MLG & other things & higher drag wing.

Now after knowling fuel used, distance traversed per second at Supercruising speed with 100% thrust level, if people can obtain the same data at say Mach 0.7-0.8, then merit/demerit of Supercruise can be debated.

But the R&D to increase speed, distance travelled in minimum fuel used will never stop.

The worst forum i have seen so far:

We cant attach diagrams, images. So black & white.
We can't message anyone.
Every message requires approval.
DFI/DFB Vs this defence.in is like today's phone Vs Nokia 3310.

Bhartiya Sainik said:

Agenda - supercruise
Can AMCA SUPERCRUISE with F414?
SHOULD AMCA supercruise withF414?
What kind of questions are these?

Supercruising is not about just squeezing out thrust from engines but also requires aerodynamic shaping of jets, good lift by wings &/or lifting body, variable cycle engine, inlet geometry control, pressure recovery & air flow management, etc.
NOTE - Afterburner thrust & MTOW are not required to consider. 50-70% fuel & std. A-A load is used.

Benefits of Supercruise -
- Higher launch altitude & velocity gives higher weapon range & NEZ (No Escape Zone)
View attachment 2239
- Supercruising jet has better chances to conceal IR signature compared to afterburner using jet.
- Evade incoming missile

But aircrafts also have to overcome air-friction & sonic drag forces.
At transonic speeds the sonic drag increases suddenly & sharply then falls towards Mach 2.
View attachment 2240
So ideally an aircraft should supercruise beyond Mach 1.8 at least. The danger zone is 0.9 to 1.5

Also, there is the "Whitcomb Area Rule" to shape a fuselage of jet to reduce the drag. Supersonic Area rue also there as per which the aircraft body need to be within the Sonic-Cone. These rules are being used in almost all jets i think. there could be more rules which we civilians enthusiasts may nor know yet.

Given any engine with an inlet diameter, it is upto designer how much thrust can be squeezed out. Engineers either do not know that limit or it is above top secret.
We already saw in previous posts the parameters required for airframe & engine performace.

2 same jets with different wing & fuselage design but with same # & type of engine(s) will have different performance.

Different sources give different data on Supercruise
For example F-22,
View attachment 2241
Fuel consumption is measured in units like g/KN/s or lb/lbf/hr, called SFC or Specific Fuel Consumption.

F-22's F119 engine's SFC with inlet dia. 100cm at 100% power (116-120.3 KN) is around 17 g/KN/s.
2 engines, so F-22 SFC is 34 g/KN/s at 100% power & Sup.Cr. Mach 1.5-1.8 (514.5-617.4 m/s).
So 3.94-4Kg/s fuel for covering 514.5-617.4 m/s or 128.6-156.7 m/Kg or 6.38-7.77 gm/m.
Empty weight 19.7 T + 50% fuel 4.1 T + full IWB 8 AAMs 1.1 T = 24.9 tons
Airframe T/W ratio at 100% power = 2x(116 to 120.3)/9.8 /24.9 = 0.94 to 0.98
Fuel per ton = (3,940-4,000)/24.9 = 158.23-160.64 gm/s/T.
50% fuel 4.1 tons while supercruise will be depleted in 1,025-1040 seconds or 17-18 minutes covering 527-642 Kms.

F-35's F-135 engines SFC with inlet dia. 109cm at 100% power (128.1 KN.) is around 20.3 g/KN/s.
Sup.Cr. M1.2 (411.6 m/s).
So 2.6 Kg/s fuel for covering 411.6m.s or 158.3 m/Kg or 6.31 gm/m.
But to go this extra 30m/Kg-fuel Vs F-22, the SFC is increased from 17 to 20.3 g/KN/s.
F-35A Empty weight 13.3 T + 50% fuel 4.15 T + 4 AAMs 0.6 T = 18.05 tons
Airframe T/W ratio at 100% power = 128.1/9.8 /18.05 = 0.72
Fuel per ton = 2,600/18.05 = 144.04 gm/s/T.
50% fuel 4.15 tons while supercruise will be depleted in 1,596 seconds or 26.6 minutes covering 675 Kms.
So we see that F135 engine has more thrust but higher SFC than F119 engine,
& F-35 goes further /Kg fuel, consumes less fuel per unit distance, per ton of body BUT has lower T/W ratio and cannot supercruise.

GE F-414 engine's SFC with inlet dia. 79cm at 100% power (57.8-61.83 KN) is 20.5-23.25 g/KN/s depending upon model. 75 KN JV engine is planned.
2 engines, so AMCA SFC will be 41-46.5 g/KN/s at 100% power.
So 2.37-2.87Kg/s fuel will be used.
AMCA empty weight 12 T + 50% fuel 3.25 T + 4 Astr MK3 SFDR 0.88 T = 16.13 tons
T/W ratio at 100% power = 2x58/9.8 /16.13 = 0.73
Fuel per ton = (2,370-2,870)/16.13 = 146.93-177.92 gm/s/T.
let's assume that with 0.73 T/W AMCA can also supercruise at M 1.2 (411.6 m/s).
50% fuel 3.25 tons while on supercuise will be depleted in 1,132-1,371 seconds or 18-23 minutes covering 466-564 Kms.
When new engine with 75 KN dry thrust will be available then hopefully 6 AAMs will be carried.
T/W ratio at 100% power = 2x75/9.8 / (16.13 + 0.44) = 0.92
Then hopefully AMCA will supercruise around M 1.5

NOTE - Among these 3 engines F414 is smallest engine with highest SFC at 100% power.
NOTE - IDK what is the SFC of these engines at say Mach 0.7 & what is the throttle position. I think these kind of parameters are secret. Sometimes these fiigures are calculated at full IWB load, sometimes AA load + 50%-80% fuel dpending upon fuel left after reaching 35-40K feet altitude & supercruise speed.

Rafale's M-88-2 engine's SFC with inlet dia. 70cm at 100% power (50KN) is 22.14 g/KN/s.
2 engines, so Rafale SFC is 44.28 g/KN/s at 100% power & Sup.Cr. Mach 1.4 (480.2 m/s).
So 2.21 Kg/s fuel for covering 480.2 m/s or 217.28 m/Kg or 4.6 gm/m.
To go this extra 59 m/Kg-fuel Vs F-35, the SFC is increased from 20.3 to 22.14 g/KN/s.

EF-2000's EJ-200 engine's SFC with inlet dia. 74cm at 100% power (60 KN) is 21-23 g/KN/s.
2 engines so EF-2000 SFC is 42-46 g/N/s at 100% power & Sup.Cr. Mach 1.5 (514.5 m/s).
so 2.52-2.76 Kg/s fuel for covering 514.5 m/s or 186.41-204.16 m/Kg or 4.9-5.36 gm/m.

So we see that Rafale with empty design weight 8.5 T, 492 sqft clipped delta wing & 50KN engine can supercruise at M 1.4
but F-18E/F with empty design weight 14.5 T, 500 sqft. trapezoidal wing & 58 KN engine cannot due to 6T weight increase due to carrier-ops MLG & other things & higher drag wing.

Now after knowling fuel used, distance traversed per second at Supercruising speed with 100% thrust level, if people can obtain the same data at say Mach 0.7-0.8, then merit/demerit of Supercruise can be debated.

But the R&D to increase speed, distance travelled in minimum fuel used will never stop.

Click to expand...

Made a table out of Bhartiya Sainik's detailed analysis. Will fill out and complete the table later

If kf 21 can super cruise with f-414 than most likely amca will also be able to super cruise with f-414.

Anyway F-414 has features suitable for supercruise so any Airframe within reasonable weight limits and aerodynamic design optimized for supercruise should be able to achieve super sonic speeds without afterburner.

Turboprops have high efficiency at subsonic speeds.
Tubojets have high efficiency at super sonic speeds.
Ramjets have high efficiency at mach 2.5+.
Scramjets have high efficiency at hypersonic speeds.


Turbofans are a compromise between turobojets and turbofan. Increase bypass ratio and you will get high thrust and high subsonic efficiency. Reduce bypass ratio and you will lose efficiency at subsonic speeds but the efficiency will be higher at mach 1+ speeds. That is why most supercruising planes engine are very low bypass engine.


So idealy F-414 with it's bypass ratio of .3 should allow supercruise if thrust to weight ratio and aerodynamics are favorable.

Now only thing that matter is weather drdo will be able to control weight of amca or not.

Another issue is weather f414 is able deliver desired thrust in indian conditions or not.

Kattar said:

Made a table out of Bhartiya Sainik's detailed analysis. Will fill out and complete the table later

AIRCRAFT	WEIGHT in Tons	ENGINE	MAX DRY THRUST in KN	FUELWEIGHT in TONS @ 50%	SFC in g/KN/s (x No of Engines)	INLET DIA in CMs	No of AAMs	Total Combat Weight in Tons (Empty + Fuel + AAMs)	Supercruise Speed in Mach (m/s)	Distance covered for every KG of fuel in m/KG	Projected duration of SuperCruise in Minutes	Projected Distance of SuperCruise in KMs
F-22	19.7	F-119	116-120.3	4.1	17 (34)	100	8	24.9 (19.7+4.1+1.1)	1.5-1.8 (514.5-617.6)	128.6-156.7	17-18	527-642
F-35	13	F-135	128.1	4.15	20.3	109	4	18.05 (13.3+4.15+0.6)	1.2 (411.6)		26.6	675
AMCA	12	F-414	57.8-61.83	3.25	20.5-23.25 (41-46.5)	79	4	16.13 (12+3.25+4)	1.2 (411.6)	146.93-177.92	18-23	466-564
RAFALE	8.5	M88-2	50		22.14 (44.28)	70			1.4 (480.2)	217.28
F-18 E/F	14.5		58
EUROFIGHTER 2000		EJ 200	60		21-23 (42-46)	74			1.5 (514.5)	186.41-204.16

Click to expand...

Good job. I tried copy-pasting the excel sheet but after posting the table was looking like ladder so i pasted it 1st in MS-Paint then here as a pic.
For airframe performace it would be good also to include fuel used in terms of
Airframe SFC (Engine SFC x # of engines x dry KN thrust) = Kg/s
& Gm/m @ 100% dry thrust.

Other members should also contribute in comparisons & making corrections if required & fill in values unavailable yet. Certain pages may not open in certain countries.

Kattar said:

Made a table out of Bhartiya Sainik's detailed analysis. Will fill out and complete the table later

AIRCRAFT	WEIGHT in Tons	ENGINE	MAX DRY THRUST in KN	FUELWEIGHT in TONS @ 50%	SFC in g/KN/s (x No of Engines)	INLET DIA in CMs	No of AAMs	Total Combat Weight in Tons (Empty + Fuel + AAMs)	Supercruise Speed in Mach (m/s)	Distance covered for every KG of fuel in m/KG	Projected duration of SuperCruise in Minutes	Projected Distance of SuperCruise in KMs
F-22	19.7	F-119	116-120.3	4.1	17 (34)	100	8	24.9 (19.7+4.1+1.1)	1.5-1.8 (514.5-617.6)	128.6-156.7	17-18	527-642
F-35	13	F-135	128.1	4.15	20.3	109	4	18.05 (13.3+4.15+0.6)	1.2 (411.6)		26.6	675
AMCA	12	F-414	57.8-61.83	3.25	20.5-23.25 (41-46.5)	79	4	16.13 (12+3.25+4)	1.2 (411.6)	146.93-177.92	18-23	466-564
RAFALE	8.5	M88-2	50		22.14 (44.28)	70			1.4 (480.2)	217.28
F-18 E/F	14.5		58
EUROFIGHTER 2000		EJ 200	60		21-23 (42-46)	74			1.5 (514.5)	186.41-204.16

Click to expand...

1) F35 is not supercruising : it can't go beyond mach 1 without reheat, and can only sustain mach 1+ without AB in slight descent.
2) Rafale is not 8.5T in dry. It is more 9T5 (Version C : 9350 kg, Version B : 9550 kg, Version M : 9950 kg)

Correct me if i'm wrong but wasn't super cruise just a marketing term for the F22, as it's supercruise was sustained above mach 1.5 and around 1.8?

Like the term hypersonic weapon, although the literal term meaning moving faster than mach 5, it's universally agreed upon that in the military sense is it's the ability to maneuver greatly at speeds above mach 5.

Therefore I thought supercruising below mach 1.5 didn't really count as real supercruise as it is very inefficient due to the drag. Therefore I don't believe KF-21 can supercruise >1.5 with it's F414.

Therefore AMCA should target >mach 1.5 supercruise.
Although I could be wrong please correct me if am so.

Kontakt5 said:

Correct me if i'm wrong but wasn't super cruise just a marketing term for the F22, as it's supercruise was sustained above mach 1.5 and around 1.8?

Like the term hypersonic weapon, although the literal term meaning moving faster than mach 5, it's universally agreed upon that in the military sense is it's the ability to maneuver greatly at speeds above mach 5.

Therefore I thought supercruising below mach 1.5 didn't really count as real supercruise as it is very inefficient due to the drag. Therefore I don't believe KF-21 can supercruise >1.5 with it's F414.

Therefore AMCA should target >mach 1.5 supercruise.
Although I could be wrong please correct me if am so.

Click to expand...

If it is like the 5G definition invented by LM, some margins are likely :
F35 is said to be 5G but fail to meet 3 or 4 of the 5 "5G" exigences : not supercruising at all, the sensor fusion is not fine (but they will fix it), it is not as agile as a F16, it is not affordable. Only OK for Stealth.
If F22 is the standard for supercruise, then supercruise is >= mach 1.8....

BON PLAN said:

If it is like the 5G definition invented by LM, some margins are likely :
F35 is said to be 5G but fail to meet 3 or 4 of the 5 "5G" exigences : not supercruising at all, the sensor fusion is not fine (but they will fix it), it is not as agile as a F16, it is not affordable. Only OK for Stealth.
If F22 is the standard for supercruise, then supercruise is >= mach 1.8....

Click to expand...

Okay thank you, so >= mach 1.8 should be 'true' supercruise target.

Kontakt5 said:

Okay thank you, so >= mach 1.8 should be 'true' supercruise target.

Click to expand...

There is a chart somewhere, (here perhaps) showing a steep fall in supersonic drag until roughly mach 1.8 is reached.