AMCA - Advanced Medium Combat Aircraft

[scholar of war]

If i sort the sheet based on T/W ratio &/or bypass ratio then the list will become random & staggered w.r.t. airframe size/weight bcoz the # of engines also differ.
Perhaps i need to make a separate engine comparison list.

Brother this is what I am saying.

Engines with similar levels of tech can have vast weight and thrust difference.

let's compare 4 engine with similar level of tech.
Engine || Dry T/W || By-Pass Ratio || TET || Weight(KG) || Thrust(wet)(KN)||
EJ-200 || 6 || .4 || 1527 C || 988 || 90 ||
M-88 || 5.68 || .3 || 1577 C || 897 || 75 ||
F-414 || 5.3 || .3 || ~1600 C || 1110 || 98 ||
F-119 || 5.21 || .3 || 1649 C || 2270 || 156(flat nozzle) ||

as you can see these similar levels of tech engines have similar dry thrust-to-weight ratios as well as similar bypass ratios.
EJ-200 despite having the lowest turbine entry temperature has the highest T/W ratio because of it's higher bypass ratio.

My viewpoint is that by-pass ratio, TET and T/W ratio are better parameters to compare tech than simply the value of wet thrust. But you can have a different viewpoint and we can agree to disagree.

A similar analogy can alsobe used to compare CPUs from different vendors that is to compare the architecture of CPUs core instead of pure numbers as different CPUs have different numbers of cores and different power consumption.

 

[Neil (नील/Нил)]

Isn't the whole CATS programme mainly geared towards this kinda thing only. You can mount jammers, IR, decoys and other radars on expendable assets and 'send ahead' of your manned platforms (connected via a data link) which stay back in relative safety, essentially making them a command and control unit. Medium sized ones will even carry missiles. The unmanned assets can even guide the payload to the target, in theory.

Whats missing is a really long range standoff weapon. Astra mk 3 will give us some of the range but IMO if one is to make this kind of tactic into a doctrine, they should have two stage ammunitions (at least for A2A). The purpose of the first stage would be to just provide range as fast as possible, which can be dropped off after doing its thing, making the rest of the missile/ammunition lighter and as maneuverable as the current ones. The second stage can then function as a normal missile. It will make the payload heavier but doing it on your non expendable heavier manned assets is a lot more achievable than making your unmanned assets heavier and keeping them cheap.
This will help make your manned platfoms stay a lot behind and safe. Ofc, a reliable and safe data link will also be needed.
Without this (again IMHO), you would either have to depend on payloads carried by your unmanned assets which will have lower payload capacity due to smaller size, making them shorter in range, OR your manned assets will have to be a lot closer behind, making them more vulnerable to enemy fire.

In my mind, this should be the obvious progression before more reliably autonomous unmanned assets enter service which can be commanded from a ground station and just given missions to execute. For now this remains almost a stuff of sci-fi.

CATS Warrior is being developed for similar roles as what the SPEAR-EW will be able to accomplish. Both CATS and SPEAR-EW are in similar stages of development, both are on paper and only put forth as a concept. HAL had showcased a full-scale mockup of the CATS Warrior at the Aero India 2021 Airshow. We have several mockups of SPEAR-EW showcased by MBDA in various defence expos. But more or less, existing only as a concept and as scale models, both have yet to be tested from a real life platform but both will enter service in the near future.

SPEAR-EW mockup by MBDA.


CATS Warrior Mockup by HAL.


In case you want to understand how SPEAR-EW works: For example an F-35 is carrying several SPEAR-EW jammers (internally & hence it will have the advantage of Stealth in the sense it won't be detected immediately) and is performing a SEAD mission to destroy SAM threats like S-400, S-300, S-125 etc then it will detect the SAM & fire the SPEAR-EW at the SAM, ofcource the SAM won't sit like some sitting duck, they too will retaliate & fire missiles against the jammers but I suppose that by the time they manage to detect and are able to counter act then many of the SPEAR EW would have got close enough to the SAM to be able to employ jamming against it and this would be able to blind the SAM & help the F-35 itself or if it having escorts like F-15, E-18 Growler, F-16 etc then they will be able to get close enough to fire anti radiation missiles like AGM-88 HARM.

Something like a SPEAR EW will be a lot more cheaper and the biggest advantage is that you can carry a lot more of these when performing a mission like SEAD operations. SPEAR-EW is a lot more lighter too, you can carry a lot of them. It will be a more effective to throw a barrage of SPEAR-EW at your enemy to confuse them than a few CATS. Both have their pros and cons, I think you will agree with this.

I think we should do it this way. Yes we need to work on CATS Warrior because the future combat will demand more participation of drones and other unmanned platforms but we should also work on making a self propelled jammer that can be used not just from our fighter jets but also from our own Wingman drones. CATS warrior is projected to carry short range air-to-air missiles internally so it could in theory also carry an indigenous/desi self-propelled jammer too.

Imagine it this way. An AMCA or Tejas Mk-1A/2 is commanding a flight of 6 CATS Warriors. Three of the CATS warriors are armed with only air-to-air missiles, and the remaining three are armed with four "SPEAR-EW's. So that will make it 3 x 4 = 12 SPEAR EW. And the numbers can be increased a lot more if you want to really saturate and overwhelm a SAM system. With enough CATS Warrior drones operating in conjunction with a host/mothership aircraft and the drones themselves armed with a variety of weapons such as air-to-air missiles, self propelled jammers, glide bombs, ARM etc, it will be a force to be reckon with.

HAL CATS WARRIOR.


I think you should understand it this way: if the Idea of a self propelled jammer was not a pragmatic or logical concept as implied by you, why would MBDA bother to continue developing it? I think you will have your answer there.

 

[Azaad]

CATS Warrior is being developed for similar roles as what the SPEAR-EW will be able to accomplish. Both CATS and SPEAR-EW are in similar stages of development, both are on paper and only put forth as a concept. HAL had showcased a full-scale mockup of the CATS Warrior at the Aero India 2021 Airshow. We have several mockups of SPEAR-EW showcased by MBDA in various defence expos. But more or less, existing only as a concept and as scale models, both have yet to be tested from a real life platform but both will enter service in the near future.

SPEAR-EW mockup by MBDA.
View attachment 1494

CATS Warrior Mockup by HAL.
View attachment 1493

In case you want to understand how SPEAR-EW works: For example an F-35 is carrying several SPEAR-EW jammers (internally & hence it will have the advantage of Stealth in the sense it won't be detected immediately) and is performing a SEAD mission to destroy SAM threats like S-400, S-300, S-125 etc then it will detect the SAM & fire the SPEAR-EW at the SAM, ofcource the SAM won't sit like some sitting duck, they too will retaliate & fire missiles against the jammers but I suppose that by the time they manage to detect and are able to counter act then many of the SPEAR EW would have got close enough to the SAM to be able to employ jamming against it and this would be able to blind the SAM & help the F-35 itself or if it having escorts like F-15, E-18 Growler, F-16 etc then they will be able to get close enough to fire anti radiation missiles like AGM-88 HARM.

Something like a SPEAR EW will be a lot more cheaper and the biggest advantage is that you can carry a lot more of these when performing a mission like SEAD operations. SPEAR-EW is a lot more lighter too, you can carry a lot of them. It will be a more effective to throw a barrage of SPEAR-EW at your enemy to confuse them than a few CATS. Both have their pros and cons, I think you will agree with this.

I think we should do it this way. Yes we need to work on CATS Warrior because the future combat will demand more participation of drones and other unmanned platforms but we should also work on making a self propelled jammer that can be used not just from our fighter jets but also from our own Wingman drones. CATS warrior is projected to carry short range air-to-air missiles internally so it could in theory also carry an indigenous/desi self-propelled jammer too.

Imagine it this way. An AMCA or Tejas Mk-1A/2 is commanding a flight of 6 CATS Warriors. Three of the CATS warriors are armed with only air-to-air missiles, and the remaining three are armed with four "SPEAR-EW's. So that will make it 3 x 4 = 12 SPEAR EW. And the numbers can be increased a lot more if you want to really saturate and overwhelm a SAM system. With enough CATS Warrior drones operating in conjunction with a host/mothership aircraft and the drones themselves armed with a variety of weapons such as air-to-air missiles, self propelled jammers, glide bombs, ARM etc, it will be a force to be reckon with.

HAL CATS WARRIOR.
View attachment 1490View attachment 1491

I think you should understand it this way: if the Idea of a self propelled jammer was not a pragmatic or logical concept as implied by you, why would MBDA bother to continue developing it? I think you will have your answer there.

F-35 in itself is a VLO platform , why should it be escorted by Eagles & Hornets or Vipers ? The configuration for such missions would be Raptors or NGAD escorting the Lightnings. Any other escort & it defeats the entire purpose.

These EW platforms aren't meant to take out SAMs but for such targets as HPRs / OTH / BMD sites / C&C sites , etc . Put another way it's to neutralize high value targets in an ISR saturated environment.

A platform like CATS Warrior makes more sense for a relatively LO platform like the Mk-2 although it'd also serve the same purpose for an AMCA Mk-1 . Perhaps with modifications it can also serve the TEDBF.

 

[Neil (नील/Нил)]

F-35 in itself is a VLO platform , why should it be escorted by Eagles & Hornets or Vipers ? The configuration for such missions would be Raptors or NGAD escorting the Lightnings. Any other escort & it defeats the entire purpose.

I just gave an example above to explain how the SPEAR-EW would work using the F-35 as a launch platform and aircraft such as the E-18, F-15, F-16 as escort. Besides SEAD operations can be performed in different configurations. It can be this way:
1. Stealth + Non-Stealth.
2. Stealth + Stealth.
3. Non-Stealth + Non-Stealth.

"Stealth + Stealth" would be a lot more expensive than "Non-Stealth + Non-Stealth"/"Stealth + Non-Stealth". Simply because of the fact that stealth aircraft have higher operating, maintainance cost and cost per flying hour etc and they can't have the payload capacity of Non-Stealth aircraft because to maintain their VLO/LO characteristics, they need to carry weapons internally unless you want to switch to beast mode.

At the end of the day, it really depends upon you and how also well defended the enemy SAM layer is.

These EW platforms aren't meant to take out SAMs but for such targets as HPRs / OTH / BMD sites / C&C sites , etc . Put another way it's to neutralize high value targets in an ISR saturated environment.

Wrong. They are meant to take any kind of High value targets in an contested environment. A SAM is a high value target and taking them out during times of war is one of the first priority.

A platform like CATS Warrior makes more sense for a relatively LO platform like the Mk-2 although it'd also serve the same purpose for an AMCA Mk-1 . Perhaps with modifications it can also serve the TEDBF.

Yes it will also be able to serve as a wingman for the TEDBF because along with IAF, CATS Warrior is also being developed for use by the Indian Navy as well. But my point was about a self propelled jammer and why I think we should work on making something similar. Already covered the same in my previous post.
Post in thread 'AMCA - Advanced Medium Combat Aircraft' https://defenceforumbharat.com/threads/amca-advanced-medium-combat-aircraft.110/post-2870

 

[fire starter]

*Radome assembly with RAS
*ITO coated windscreen & canopy.
*sandwich RAS fairing and cover.
* RCS test bed.

 

[Bhartiya Sainik]

Regarding infrared stealth here is the paper by ADA for active cooling of engine bay and nozzle for stealth aircraft.

Feasibility study of engine bay ventilation with intake air driven by ejector nozzle.
View attachment 1449

In this approach nozzle of engine will be covered by ejector inlet.

View attachment 1450
View attachment 1452

(PDF) Feasibility study of engine bay ventilation with intake air driven by ejector nozzle

PDF | Feasibility study of engine bay ventilation with intake air driven by ejector nozzle Abhijit Dhamanekar, Aishwarjya Gogoi ABSTRACT The present... | Find, read and cite all the research you need on ResearchGate

www.researchgate.net

It seems to be already used in some or all jets.

F-18 E/F



A16 = ECS ram-air inlet in engine duct
A17 = ECS auxilliary air inlet
A18 = ECS primary HX (Heat Exchanger)
A19 = ECS Package (Hamilton Sundstrand)
A20 = ECS exhaust
A21 = ECS secondary HX
132 = ECS auxilliary inlet door

Additionally the cooling of engine bays & other areas including cockpit happens in multiple ways by ECS (Environmental Control System) -
1> similar to in civil jets - BLEED-AIR is taken from compressor stages & HVAC & crew/passenger cabin pressurization is handled by mixers & heat exchangers.
2> air is taken by scoops near the cockpit, airframe intake, near the engines. Air exits also by nearby vents.
3> Dedicated coolant system for airframe. There is a coolant reservoir from which critical parts of airframe get plumbing network.

Air scoop, Ram-air inlets
Example - F-18 A/B/C/D, not in E/F



somewhere else on top on F-18 E/F



But in stealth jet such inlets on airframe cannot be there.
F-22 air scoop is in boundary layer splitting gap. For stealth there doesn't seem to be any other scoop.
There could be ram-air inlet inside the duct.



one of the ECS steam exhaust is above left IWB. It is labled also on its side



Those 6 diamond shaped areas are ventilation screens. There are no scoops to be seen.



Vapours, most likely steam or something can be seen coming out of those vent screens.



But F-22 & F-35 have circulated coolant based system.

F-35
2 scoops are at wing root just ahead of MLG



It is characteristics of stealth aircraft to prioritise complete comprehensive thermal management by air, liquid, heat-resistant materials, etc meaning more heat exchangers, pumps, plumbing leading to weight increase which has to be countered by a better engine to maintain certain total thust / airframe weight ratio.

 

[Gutenmorgen]

F-35 in itself is a VLO platform , why should it be escorted by Eagles & Hornets or Vipers ? The configuration for such missions would be Raptors or NGAD escorting the Lightnings. Any other escort & it defeats the entire purpose.

These EW platforms aren't meant to take out SAMs but for such targets as HPRs / OTH / BMD sites / C&C sites , etc . Put another way it's to neutralize high value targets in an ISR saturated environment.

A platform like CATS Warrior makes more sense for a relatively LO platform like the Mk-2 although it'd also serve the same purpose for an AMCA Mk-1 . Perhaps with modifications it can also serve the TEDBF.

CATS also has a similar component called Hunter. In an interview (can't remember, maybe DDR) it was mentioned that it can carry radars, jammers, smaller drones or an explosive warhead.
At least I cant see much difference between this and Spear-ew, except the latter is being designed for an IWB from the get go. If anything, hunter seems more versatile.

 

[Neil (नील/Нил)]

Future 6th generation aircraft after AMCA.
After the AMCA's development, ADA would have gained the necessary/required expertise to work on a 6th generation aircraft.
It's possible that ADA is working on developing 6th generation aircraft technology right now in parallel with the AMCA, and this makes sense.
As time passes, technology also progresses and our regional rival China is already actively working on developing it's own 6th generation aircraft after the J-20 and to counter it, we will need our own domestic 6th generation jet.
The Su-30MKIs will remain the IAF's back-bone for up till the 2040s with the Super Sukhoi Upgrade.
After that what will replace Su-30MKI? I think India should make an AHCA on the expertise gained in the development of the AMCA.
AHCA should be a 5.5+/6th generation heavy weight aircraft in the future.
AMCA Mk-1 and AMCA Mk-2 will be fifth generation aircraft in medium weight category. But a 6th generation aircraft cannot be in the medium weight as the level of sophistication in a future 6th-gen plane.
The thrust requirement, the power requirements to run the on-board computers, processors and other electronics of a 6th generation aircraft simply won't be possible to implement on a medium weight body, so size will have to increase no matter what. Even NGAD will be in heavy weight category.
From online sources that I have managed to gather:
F-22 being a heavy weight 5th generation fighter has an empty weight of around 19.7 tons.
NGAD is supposed to weigh upwards of 22 tons or more.
NOTE: I cannot give a precise estimate as there isn't actually much information about the NGAD's projected specifications. I am only basing this number on an infographic I saw online.
The NGAD is supposed to be much more expensive in terms of costs than the F-22 and F-35. It's supposed to cost almost 3-4 times as much as an F-35. This is expected, any new technology during its release will be expensive but over time the same technology will become less expensive and will become more economical with time.
There was a time when 1st generation aircraft were the backbone of most major airforces around the world. Then when 2nd generation planes made their debut freshly, they were deemed too expensive and non-economical to induct in large numbers as compared to 1st generation aircraft, as a result very few airforces could develop their own Indigenous 2nd-gen jets.
The same happened with 2nd generation when 3rd generation planes came out for the first time, same is the case with 4th when 5th came out and it will be the same case when 6th generation aircrafts start coming out gradually.

 

[SwordOfDarkness]

Future 6th generation aircraft after AMCA.
After the AMCA's development, ADA would have gained the necessary/required expertise to work on a 6th generation aircraft.
It's possible that ADA is working on developing 6th generation aircraft technology right now in parallel with the AMCA, and this makes sense.
As time passes, technology also progresses and our regional rival China is already actively working on developing it's own 6th generation aircraft after the J-20 and to counter it, we will need our own domestic 6th generation jet.
The Su-30MKIs will remain the IAF's back-bone for up till the 2040s with the Super Sukhoi Upgrade.
After that what will replace Su-30MKI? I think India should make an AHCA on the expertise gained in the development of the AMCA.
AHCA should be a 5.5+/6th generation heavy weight aircraft in the future.
AMCA Mk-1 and AMCA Mk-2 will be fifth generation aircraft in medium weight category. But a 6th generation aircraft cannot be in the medium weight as the level of sophistication in a future 6th-gen plane.
The thrust requirement, the power requirements to run the on-board computers, processors and other electronics of a 6th generation aircraft simply won't be possible to implement on a medium weight body, so size will have to increase no matter what. Even NGAD will be in heavy weight category.
From online sources that I have managed to gather:
F-22 being a heavy weight 5th generation fighter has an empty weight of around 19.7 tons.
NGAD is supposed to weigh upwards of 22 tons or more.
NOTE: I cannot give a precise estimate as there isn't actually much information about the NGAD's projected specifications. I am only basing this number on an infographic I saw online.
The NGAD is supposed to be much more expensive in terms of costs than the F-22 and F-35. It's supposed to cost almost 3-4 times as much as an F-35. This is expected, any new technology during its release will be expensive but over time the same technology will become less expensive and will become more economical with time.
There was a time when 1st generation aircraft were the backbone of most major airforces around the world. Then when 2nd generation planes made their debut freshly, they were deemed too expensive and non-economical to induct in large numbers as compared to 1st generation aircraft, as a result very few airforces could develop their own Indigenous 2nd-gen jets.
The same happened with 2nd generation when 3rd generation planes came out for the first time, same is the case with 4th when 5th came out and it will be the same case when 6th generation aircrafts start coming out gradually.

View attachment 1880View attachment 1881View attachment 1882

As of now, there is nothing as "6th gen"

6th gen is a marketting gimmic used for mature 5th gen designs.

Actual 6th gen will come with either hypersonic stealth fighters or with fully autonomous fighters. Before that, everything is 5th gen.

 

[Satish Sharma Ji]

As of now, there is nothing as "6th gen"

6th gen is a marketting gimmic used for mature 5th gen designs.

Actual 6th gen will come with either hypersonic stealth fighters or with fully autonomous fighters. Before that, everything is 5th gen.

Yeah whatever the components they say of 6th gen can be equipped with/on 5g.
Laser weapons, wing mans actually 6th gen would way ahead that we can imagine. Usa/china would be the trend setter

 

[Gutenmorgen]

@Neil (नील/Нил)
Whoops.. Sorry, my last reply was meant for your earlier post..

CATS Warrior is being developed for similar roles as what the SPEAR-EW will be able to accomplish. Both CATS and SPEAR-EW are in similar stages of development, both are on paper and only put forth as a concept. HAL had showcased a full-scale mockup of the CATS Warrior at the Aero India 2021 Airshow. We have several mockups of SPEAR-EW showcased by MBDA in various defence expos. But more or less, existing only as a concept and as scale models, both have yet to be tested from a real life platform but both will enter service in the near future.

SPEAR-EW mockup by MBDA.
View attachment 1494

CATS Warrior Mockup by HAL.
View attachment 1493

In case you want to understand how SPEAR-EW works: For example an F-35 is carrying several SPEAR-EW jammers (internally & hence it will have the advantage of Stealth in the sense it won't be detected immediately) and is performing a SEAD mission to destroy SAM threats like S-400, S-300, S-125 etc then it will detect the SAM & fire the SPEAR-EW at the SAM, ofcource the SAM won't sit like some sitting duck, they too will retaliate & fire missiles against the jammers but I suppose that by the time they manage to detect and are able to counter act then many of the SPEAR EW would have got close enough to the SAM to be able to employ jamming against it and this would be able to blind the SAM & help the F-35 itself or if it having escorts like F-15, E-18 Growler, F-16 etc then they will be able to get close enough to fire anti radiation missiles like AGM-88 HARM.

Something like a SPEAR EW will be a lot more cheaper and the biggest advantage is that you can carry a lot more of these when performing a mission like SEAD operations. SPEAR-EW is a lot more lighter too, you can carry a lot of them. It will be a more effective to throw a barrage of SPEAR-EW at your enemy to confuse them than a few CATS. Both have their pros and cons, I think you will agree with this.

I think we should do it this way. Yes we need to work on CATS Warrior because the future combat will demand more participation of drones and other unmanned platforms but we should also work on making a self propelled jammer that can be used not just from our fighter jets but also from our own Wingman drones. CATS warrior is projected to carry short range air-to-air missiles internally so it could in theory also carry an indigenous/desi self-propelled jammer too.

Imagine it this way. An AMCA or Tejas Mk-1A/2 is commanding a flight of 6 CATS Warriors. Three of the CATS warriors are armed with only air-to-air missiles, and the remaining three are armed with four "SPEAR-EW's. So that will make it 3 x 4 = 12 SPEAR EW. And the numbers can be increased a lot more if you want to really saturate and overwhelm a SAM system. With enough CATS Warrior drones operating in conjunction with a host/mothership aircraft and the drones themselves armed with a variety of weapons such as air-to-air missiles, self propelled jammers, glide bombs, ARM etc, it will be a force to be reckon with.

HAL CATS WARRIOR.
View attachment 1490View attachment 1491

I think you should understand it this way: if the Idea of a self propelled jammer was not a pragmatic or logical concept as implied by you, why would MBDA bother to continue developing it? I think you will have your answer there.

CATS also has a similar component called Hunter. In an interview (can't remember, maybe DDR) it was mentioned that it can carry radars, jammers, smaller drones or an explosive warhead.
At least I cant see much difference between this and Spear-ew, except the latter is being designed for an IWB from the get go. If anything, hunter seems more versatile.

 

[Spitfire IX]

Whatever characteristics 6G fighters may have, they are going to be mighty expensive. They will only be bought by countries with large defence budgets, so are unlikely to be made in large numbers boosted by exports.

That will leave a lot of air forces considering buying 5G when their 4G fighters are reaching the end of the road. IMO India could get a slice of that market with AMCA if ownership costs (including Indian missiles) were considerably lower than F-35.

6G fighters, by the sound of it, will need an engine whose technology is way beyond India's capability for the foreseeable future. Any engine developed for AMCA will not be suitable for a heavy 6G fighter.

 

[SwordOfDarkness]

Whatever characteristics 6G fighters may have, they are going to be mighty expensive. They will only be bought by countries with large defence budgets, so are unlikely to be made in large numbers boosted by exports.

That will leave a lot of air forces considering buying 5G when their 4G fighters are reaching the end of the road. IMO India could get a slice of that market with AMCA if ownership costs (including Indian missiles) were considerably lower than F-35.

6G fighters, by the sound of it, will need an engine whose technology is way beyond India's capability for the foreseeable future. Any engine developed for AMCA will not be suitable for a heavy 6G fighter.

For exports, AMCA is poorly suited. Better to go for a cheaper, reduced capability single engine light fighter.

 

[Bhartiya Sainik]

Brother this is what I am saying.
Engines with similar levels of tech can have vast weight and thrust difference.
let's compare 4 engine with similar level of tech.
Engine || Dry T/W || By-Pass Ratio || TET || Weight(KG) || Thrust(wet)(KN)||
EJ-200 || 6 || .4 || 1527 C || 988 || 90 ||
M-88 || 5.68 || .3 || 1577 C || 897 || 75 ||
F-414 || 5.3 || .3 || ~1600 C || 1110 || 98 ||
F-119 || 5.21 || .3 || 1649 C || 2270 || 156(flat nozzle) ||
as you can see these similar levels of tech engines have similar dry thrust-to-weight ratios as well as similar bypass ratios.
EJ-200 despite having the lowest turbine entry temperature has the highest T/W ratio because of it's higher bypass ratio.

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-

There is also debate on whether an adjacant component attached to engine should be included in its weight or not like TVC nozzle, cooling system, gearbox, etc.
Some say that only the parts inside the cylindrical body controlling the airflow should be part of weight. Some include external attachments like electronics & sensor boxes, plumbing for air, fuel, oil, coolant.
Some say that whatever engine company delivers, in or out of engine body, is part of weight.
The above 3 logic gives 3 different engine weights.

- 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.



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.

My viewpoint is that by-pass ratio, TET and T/W ratio are better parameters to compare tech than simply the value of wet thrust. But you can have a different viewpoint and we can agree to disagree.

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.

Different engines have different Afterburner capabilities. People usually consider wet thrust to be roughly 50% of 100% dry thrust, but it can range from 30%-72%.

A similar analogy can alsobe used to compare CPUs from different vendors that is to compare the architecture of CPUs core instead of pure numbers as different CPUs have different numbers of cores and different power consumption.

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.

 

[Wolfie]

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.

Well if you want to actually know, read about various thermodynamics cycle, gas turbine are brayton/joule cycle. Read some good book on thermodynamics. Basically better the compressor, higher the TET, higher the efficiency.

https://web.mit.edu/16.unified/www/SPRING/propulsion/notes/node27.html
Read this to get a fair idea

 

[Bhartiya Sainik]

Future 6th generation aircraft after AMCA.
After the AMCA's development, ADA would have gained the necessary/required expertise to work on a 6th generation aircraft.
It's possible that ADA is working on developing 6th generation aircraft technology right now in parallel with the AMCA, and this makes sense.

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:

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.

As time passes, technology also progresses and our regional rival China is already actively working on developing it's own 6th generation aircraft after the J-20 and to counter it, we will need our own domestic 6th generation jet.
The Su-30MKIs will remain the IAF's back-bone for up till the 2040s with the Super Sukhoi Upgrade.
After that what will replace Su-30MKI? I think India should make an AHCA on the expertise gained in the development of the AMCA.

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.

AHCA should be a 5.5+/6th generation heavy weight aircraft in the future.
AMCA Mk-1 and AMCA Mk-2 will be fifth generation aircraft in medium weight category. But a 6th generation aircraft cannot be in the medium weight as the level of sophistication in a future 6th-gen plane.

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.

The thrust requirement, the power requirements to run the on-board computers, processors and other electronics of a 6th generation aircraft simply won't be possible to implement on a medium weight body, so size will have to increase no matter what. Even NGAD will be in heavy weight category.
From online sources that I have managed to gather:
F-22 being a heavy weight 5th generation fighter has an empty weight of around 19.7 tons.
NGAD is supposed to weigh upwards of 22 tons or more.
NOTE: I cannot give a precise estimate as there isn't actually much information about the NGAD's projected specifications. I am only basing this number on an infographic I saw online.

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.

Yeah whatever the components they say of 6th gen can be equipped with/on 5g.
Laser weapons, wing mans actually 6th gen would way ahead that we can imagine. Usa/china would be the trend setter

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

Whatever characteristics 6G fighters may have, they are going to be mighty expensive. They will only be bought by countries with large defence budgets, so are unlikely to be made in large numbers boosted by exports.

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

That will leave a lot of air forces considering buying 5G when their 4G fighters are reaching the end of the road. IMO India could get a slice of that market with AMCA if ownership costs (including Indian missiles) were considerably lower than F-35.

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.

6G fighters, by the sound of it, will need an engine whose technology is way beyond India's capability for the foreseeable future. Any engine developed for AMCA will not be suitable for a heavy 6G fighter.

As workaround we will develop AHCA with 4 engines


: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.

 

[Physx32]

IDK what should be ideal Turbine Inlet Temp. for jet fighter engines but in my homework excel sheet I observed range is

The ideal Turbine inlet temperature (TIT) is as high as your blade material can withstand.

Higher the TIT, higher can be your compressor exit temperature, which means higher efficiency.

In the real world, your TIT is fixed, for e.g. 1800 K. Now, you design your compressor exit temperature based on your requirement (balancing between max efficiency and max work).

What creates this difference? Fuel type? Combuster design? Compression/Pressure ratio? Fuel-Air mix ratio?

The blade technology available to you determines your TIT. Now, to operate at that TIT, you'll set overall pressure ratio/compressor exit temperature and air-fuel ratio accordingly.

 

[Bhartiya Sainik]

The ideal Turbine inlet temperature (TIT) is as high as your blade material can withstand.

yes that's natural. The blade should not melt or crack. But we cannot heat the air indefintely in a turbofan. There could be some limit which forced people to move towards Ramjet & Scramjet research.

Higher the TIT, higher can be your compressor exit temperature, which means higher efficiency.
In the real world, your TIT is fixed, for e.g. 1800 K. Now, you design your compressor exit temperature based on your requirement (balancing between max efficiency and max work).

Why compressor exit temperature? After HPC comes the combustor which is hottest part which is at the TIT. Ingestion of air hotter than required can cause compressor stall resulting in flame-out.

The blade technology available to you determines your TIT. Now, to operate at that TIT, you'll set overall pressure ratio/compressor exit temperature and air-fuel ratio accordingly.

F-35's F-135 TIT is 2,260 K highest, but compression ratio is 28-30, not highest.
F-16E's F110-GE-132 TIT is 1,780 K not highest, but compression ratio is 33.3 highest.

 

[fire starter]

Drdo has developed innovative sliding door mechanism for amca internal weapon bay to reduce the drag.

Traditionally, the hinged door configuration with actuators is used which protrudes outside, thus experiencing the drag force.In the present study, an innovative sliding door operating mechanism is devised such that doors slide within the internal weapon bay and are minimally exposed outside.

I believe they have patented it.

 

[Bhartiya Sainik]

Drdo has developed innovative sliding door mechanism for amca internal weapon bay to reduce the drag.

Traditionally, the hinged door configuration with actuators is used which protrudes outside, thus experiencing the drag force.In the present study, an innovative sliding door operating mechanism is devised such that doors slide within the internal weapon bay and are minimally exposed outside.
View attachment 2007
I believe they have patented it.

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 :


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


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 :

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.