AMCA News and Discussions

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Re: AMCA News and Discussions

Postby Victor » 15 Oct 2014 06:59

indranilroy wrote:I don't know why it will be a brute.

Well, both LCA and AMCA lengths are mentioned as 43' in wiki but this is obviously wrong because there is no way to squish two of the same engine into an airframe and maintain the same length without looking strange and obese which the AMCA drawings certainly don't show. The Rafale is an extremely compact fighter built around an extremely compact engine and it is 50' long while the F/A-18 which uses the F414 is 56' with both their engines being about the same size (12'-13'). The AMCA illustrations resemble the latter more in general dimensions if not a little larger and is why I expect the AMCA to be about 56' to 60' long. Not exactly a brute by Su30 standards (73') but thankfully not a frugal non-violent "light" fighter either and it should be able to carry a meaningful load a long way.

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Re: AMCA News and Discussions

Postby Indranil » 15 Oct 2014 07:58

Wiki is clearly wrong on this. I expect it to be around that length as well (55'-60').

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Re: AMCA News and Discussions

Postby member_26622 » 15 Oct 2014 08:45

^^ If you notice all compact airplanes tend to be Delta wings. Length saving is basically the missing tailplane. Downside was maneuverability until the advent of unstable designs using fly by wire and thrust vectoring...

If length or compactness is main criteria then following are options in increasing length - my best guess and empirical evidence

1. Delta wing and variants - aka Tejas
2. Delta wing and variants with thrust vectoring - LCA MK II ?
3. Delta wing with canards (Euro canards - thrust vectoring likely better choice for maneuverability going by Su-35 evolution)
4. Regular configurations - the F-15,16,18 and Mig-29)
5. Super config - all combo (Fore-plane+wings+Tailplane)
6. Super Super Config (Fore-plane+wings+Tailplane+Thrust vectoring) - This is our MKI - a super kill

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Re: AMCA News and Discussions

Postby member_28714 » 15 Oct 2014 14:56

indranilroy wrote:I don't know why it will be a brute. The F-35 is under-powered for an A2A platform. It should not be a benchmark. Eurofighter is currently powered with 2 X EJ-200s. And it was supposed to be upgraded with the upgraded EJ-200s (if funds permit). AMCA cannot be as sleek through the air as the Eurofighter (internal carriage and stealth shaping). So, 2 X 110 kN might be perfect. For example the J-31 (another aircraft) of very similar role and dimensions is supposed to be powered by 2 X 100 kN (WS-13A) engines.



Its not underpowered, its just gonna be on afterburners most of the time. Lots of people will disagree but it will show up in service history in a few years when engines start failing with under 1000 hours.

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Re: AMCA News and Discussions

Postby NRao » 15 Oct 2014 17:47

George wrote:
indranilroy wrote:I don't know why it will be a brute. The F-35 is under-powered for an A2A platform. It should not be a benchmark. Eurofighter is currently powered with 2 X EJ-200s. And it was supposed to be upgraded with the upgraded EJ-200s (if funds permit). AMCA cannot be as sleek through the air as the Eurofighter (internal carriage and stealth shaping). So, 2 X 110 kN might be perfect. For example the J-31 (another aircraft) of very similar role and dimensions is supposed to be powered by 2 X 100 kN (WS-13A) engines.



Its not underpowered, its just gonna be on afterburners most of the time. Lots of people will disagree but it will show up in service history in a few years when engines start failing with under 1000 hours.


Hmmmm....

Even if all that is true, why worry about that plane, take care of your own.

The USAF has another engine waiting in the wing that is some 10-15% more powerful and some 20% more efficient.

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Re: AMCA News and Discussions

Postby brar_w » 15 Oct 2014 18:38

George wrote:
indranilroy wrote:I don't know why it will be a brute. The F-35 is under-powered for an A2A platform. It should not be a benchmark. Eurofighter is currently powered with 2 X EJ-200s. And it was supposed to be upgraded with the upgraded EJ-200s (if funds permit). AMCA cannot be as sleek through the air as the Eurofighter (internal carriage and stealth shaping). So, 2 X 110 kN might be perfect. For example the J-31 (another aircraft) of very similar role and dimensions is supposed to be powered by 2 X 100 kN (WS-13A) engines.



Its not underpowered, its just gonna be on afterburners most of the time. Lots of people will disagree but it will show up in service history in a few years when engines start failing with under 1000 hours.


Absurd!

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Re: AMCA News and Discussions

Postby member_28714 » 15 Oct 2014 18:39

brar_w wrote:
George wrote:
Its not underpowered, its just gonna be on afterburners most of the time. Lots of people will disagree but it will show up in service history in a few years when engines start failing with under 1000 hours.


Absurd!


Sure!

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Re: AMCA News and Discussions

Postby Victor » 16 Oct 2014 01:14

George wrote:Its not underpowered, its just gonna be on afterburners most of the time. Lots of people will disagree but it will show up in service history in a few years when engines start failing with under 1000 hours.

The F-35 is the only fighter that can supercruise without an engine designed for supercruise or even using wet thrust. Being such a slippery airplane (stealth shape, internal stores etc), they found it just blows past Mach 1 on dry thrust alone without a sweat. It can maintain supersonic flight like this without afterburner for about 10 minutes and this was considered more than adequate since almost all of a fighter's real work is done in the subsonic space. Under no imaginable circumstance will it be using afterburner "most of the time". That's hogwash.

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Re: AMCA News and Discussions

Postby Indranil » 16 Oct 2014 02:39

Ummm! While the statement that F-35s will be flying with AB all the time is very foolish (bordering on trolling), F-35's supercruise ability is also quite question-able. By the way, the F-35 is not more slippery than EF at supersonic speeds. At those speeds, the wave drag dominates and F-35 because of its internal carriage suffers wrt the 'finer' Eurocanards. That is why, you will hear EF/Rafale advertise that they can supercruise with weapons and external fuel above 1.3-1.4+M even though they have lesser TWR than F-35.

Also, the advertisement that F-35 can supercruise at 1.1-1.2M is a little bit of marketing. "Supercruise-capability" as others defined it is:
1. Ability to reach supercruise speed on MIL power, and
2. Ability to maintain supercruise speed at same altitude on MIL power.

While most people don't use capability 1 (too slow and fuel consuming), they want to have capability 2 when speed matters over fuel efficiency. But that trade-off must be meaningful. Being able to "supercruise" at 1.1-1.2M is not meaningful. The problem is that the difference in drag between 0.9M and 1.1M is about 2 times. So, burning twice the amount of fuel for 20% advantage in speed does not make much sense in most situations. The F-35 would do just fine cruising at 0.95M and increasing its range significantly.

That is why, whenever somebody argues that F-35/Gripen have supercruise capability, my personal response is "Well, if you want to have it on the brochure, you can have it". I am glad that ADA has not shown signs of brochuritis till now. And that's why I hope, when they say AMCA supercruise, they mean at a speeds of at least 1.4M.

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Re: AMCA News and Discussions

Postby Victor » 16 Oct 2014 04:03

F-35 does not advertise itself as supercruise-capable and in fact states that it is not designed for supercruise on its official site. The fact remains however that it does attain supersonic cruise for about 10mts/150 miles without afterburner. The definition of "supercruise" is all over the map as of today but is generally understood to mean "supersonic cruise without afterburner". No other jet can do this. The Gripen NG uses the F414G which is designed for supercruise.

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Re: AMCA News and Discussions

Postby srai » 16 Oct 2014 05:11

indranilroy wrote:...

Also, the advertisement that F-35 can supercruise at 1.1-1.2M is a little bit of marketing. "Supercruise-capability" as others defined it is:
1. Ability to reach supercruise speed on MIL power, and
2. Ability to maintain supercruise speed at same altitude on MIL power.

...


"Supercruise-capability" should also include ability to carry useful weapons payload at supercruise otherwise there is no point for a combat jet. Another would be ability to fire weapons while on supercruise mode.

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Re: AMCA News and Discussions

Postby NRao » 16 Oct 2014 05:14

As far as I know the JSF has never claimed to be super-cruise capable .............. LM, by definition, pegs super-cruise to be > Mach 1.5 and the JSF does Mach 1.2 for 150 miles. May be because of that 1.2 number people misinterpret - as they do many other aspects of that plane.

Do not even think the JSF claims to have a very "slippery" skin. Do they? ????? There are other things that are attributed to the skin, but slippery, not heard of it.

IF the Rafale/Euro crowd are glad with their pups, so be it.

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Re: AMCA News and Discussions

Postby NRao » 16 Oct 2014 05:16

srai wrote:
indranilroy wrote:...

Also, the advertisement that F-35 can supercruise at 1.1-1.2M is a little bit of marketing. "Supercruise-capability" as others defined it is:
1. Ability to reach supercruise speed on MIL power, and
2. Ability to maintain supercruise speed at same altitude on MIL power.

...


"Supercruise-capability" should also include ability to carry useful weapons payload at supercruise otherwise there is no point for a combat jet. Another would be ability to fire weapons while on supercruise mode.


weapons hanging outside will have that benefit - JSF pilots have been known to talk about that, I would imagine the pilots of other planes would too.

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Re: AMCA News and Discussions

Postby Indranil » 16 Oct 2014 05:37

Victor wrote:F-35 does not advertise itself as supercruise-capable and in fact states that it is not designed for supercruise on its official site. The fact remains however that it does attain supersonic cruise for about 10mts/150 miles without afterburner.

If it can accelerate to 1.1-1.2 M using only MIL power, then why does it slow down after 10 minutes or 150 miles? The plane only gets lighter, so it should actually have the capability to go faster as it reaches bingo fuel (as all planes do)! Actually, it is simple physics. The plane decelerates till the drag equals available engine power. Now, LM (or fanboys) decided on a definition of a supercruise. According to them, what is the minimum speed that the plane should be at (for a given config) so that it stays supersonic for 10 minutes on MIL power. That speed happens to be 1.2M and so they said F-35 "supercruises" at 1.2M. Simple procedure, use the AB to punch through to 1.2M, turn the AB off, keep the engine at full dry power, you will be supersonic for 10 minutes. For me this is twisting of facts, because this is operationally useless. Why would I not cruise at 0.95M for 10 minutes, light AB, reach maximum weapon launching speed, and launch my weapon? This will save me a lot of fuel and give me the longest possible range for the weapon!

The definition of "supercruise" is all over the map as of today but is generally understood to mean "supersonic cruise without afterburner". No other jet can do this. The Gripen NG uses the F414G which is designed for supercruise.

1. "Cruise" means to maintain same altitude and speed. Cruising while decelerating or losing altitude is the interesting part. :wink:
2. What exactly is an engine made for supercruise? All turbofan engines work with subsonic air. It is combination of engine plus airframe which makes the airplane capable of supercruise or not. All you need is sufficient and efficient dry power.

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Re: AMCA News and Discussions

Postby Victor » 16 Oct 2014 06:58

All that is being stated is that JSF can break the sound barrier and stay supersonic without using afterburner for a useful amount of time. That's all. As to why it stays supersonic for only 10 minutes, I don't have a clue. It could be the buildup of drag as you mention but I doubt it since wiki quotes Airforce Magazine saying:

"Although the Pratt & Whitney F135 F-35 engine was not designed to achieve a supercruise capability, the F-35 is able to maintain Mach 1.2 for a dash of 150 miles without using afterburners".

I suspect it is the sleek design with no pylons and other stealth details that enables this capability. The Concorde would cruise at supersonic speed without afterburners all across the Atlantic although it used afterburners for takeoff and climb to cruise, then it would shut them down. I believe XB-70 Valkyrie also could do this. Both were exceptionally clean, sleek designs.

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Re: AMCA News and Discussions

Postby Indranil » 16 Oct 2014 08:36

Victor wrote:All that is being stated is that JSF can break the sound barrier and stay supersonic without using afterburner for a useful amount of time. That's all. As to why it stays supersonic for only 10 minutes, I don't have a clue. It could be the buildup of drag as you mention but I doubt it since wiki quotes Airforce Magazine saying:

"Although the Pratt & Whitney F135 F-35 engine was not designed to achieve a supercruise capability, the F-35 is able to maintain Mach 1.2 for a dash of 150 miles without using afterburners".

All that I am saying is that JSF cannot break the speed barrier in level flight without AB. Nor can it "maintain 1.2M" without AB. Either this, or the engine or associated components cannot be running at this power continuously for more than 10 mins. I have a hard time believing this.

Also, I never said drag builds up. It is instantaneous in nature and is dependent on speed, shape, weight and density of air. I said drag should be going down in cruise (same speed, same altitude) as weight is going down.

Victor wrote:
I suspect it is the sleek design with no pylons and other stealth details that enables this capability. The Concorde would cruise at supersonic speed without afterburners all across the Atlantic although it used afterburners for takeoff and climb to cruise, then it would shut them down. I believe XB-70 Valkyrie also could do this. Both were exceptionally clean, sleek designs.

If you read why the Concorde required AB to go past the Mach 1 barrier, and then could cruise all the way across the Atlantic (without falling back to Mach 1) without using AB, you would realize why I am asserting that:
1. F-35 cannot go past the speed barrier or maintain mach 1.2 without AB.
2. Why nobody wants to fly between Mach 0.99 and Mach 1.2.

Besides, the JSF is not sleek. None of the fighters carrying bombs internally can be. It is a trade-off.

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Re: AMCA News and Discussions

Postby Victor » 16 Oct 2014 09:47

indranilroy wrote:All that I am saying is that JSF cannot break the speed barrier in level flight without AB. Nor can it "maintain 1.2M" without AB.

This is from 2010:
Pratt & Whitney’s F135 Breaks Sound Barrier on F-35B
The F-35 has supercruise capability and does not require the use of engine afterburner to achieve supersonic flight. The F135’s 28,000-pound dry thrust (without augmentor) is capable of accelerating the fighter beyond Mach one

I had read somewhere that JSF was the only jet that can do this but can't find the link now.

Anyway, I've taken this way off topic so back to the Assembly Elections dhaga for now. Adios.

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Re: AMCA News and Discussions

Postby Karan M » 16 Oct 2014 12:34

Martenji, thanks for getting the topic back from the "slippery" JSF.

http://www.indiastrategic.in/topstories ... p_Raha.htm

Exclusive Interview
Air Chief Marshal Arup Raha, Chief of the Air Staff, Indian Air Force


IS: What are your views on the – still on the drawing board – indigenous MCA (Medium Combat Aircraft) programme? How does it fit in the already crowded fighter acquisition programmes such as the MMRCA, FGFA and of course the LCA too? Also, what time horizons have been fixed for its operational induction into the IAF?

CAS: After having successfully developed the LCA indigenously, the next logical step for DRDO is to design and develop an indigenous medium category fighter aircraft which would replace some of our legacy fleets due to retire in 10-15 years time. Presently MCA is on the drawing board and it is too premature to draw out its induction timelines.

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Re: AMCA News and Discussions

Postby Indranil » 16 Oct 2014 23:41

My apologies.

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Re: AMCA News and Discussions

Postby Karan M » 17 Oct 2014 00:20

None required saar, you didnt start it..

Meanwhile, I dont understand how can the AMCA start replacing aircraft 10-15 years from now, when the design is yet to be fixed. IMHO, the IAF needs to progress this fast and join the program asap, to avoid all the previous issues we faced. Sequential step by step development with user joining late..not required.

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Re: AMCA News and Discussions

Postby brar_w » 17 Oct 2014 02:18

If it can accelerate to 1.1-1.2 M using only MIL power, then why does it slow down after 10 minutes or 150 miles? The plane only gets lighter, so it should actually have the capability to go faster as it reaches bingo fuel (as all planes do)! Actually, it is simple physics. The plane decelerates till the drag equals available engine power. Now, LM (or fanboys) decided on a definition of a supercruise. According to them, what is the minimum speed that the plane should be at (for a given config) so that it stays supersonic for 10 minutes on MIL power. That speed happens to be 1.2M and so they said F-35 "supercruises" at 1.2M. Simple procedure, use the AB to punch through to 1.2M, turn the AB off, keep the engine at full dry power, you will be supersonic for 10 minutes. For me this is twisting of facts, because this is operationally useless. Why would I not cruise at 0.95M for 10 minutes, light AB, reach maximum weapon launching speed, and launch my weapon? This will save me a lot of fuel and give me the longest possible range for the weapon!


You are getting into trouble here because you are treating "super cruise" as if it is something embedded in the dictionary or a technically acceptable term that is clearly defined and agreed upon. The modern origin of the word probably came during the 90's when the ATF program material was released. Here they specified mach 1.5 with at a desired altitude with a desired weapons load. The range (or radius) was defined with a minimum super cruise radius combined with a subsonic radius. That was it. Soon others began taking the term and applying it to older aircraft claiming they could also super cruise. Supercruise post the ATF became a sort of gospel as if one definition (as defined by the ATF for that program) was set in stone. Then came the European marketing materials and trade show delegations which started claiming that they could also super cruise. A lot of these OEM's specified a speed but were less specific on the exact load, exact altitude and what impact a particular super cruise radius would have on the overall combat radius of the aircraft (something which the ATF program baked into the specification and KPP's). So the Gripen people said we can do mach 1.1 or 1.2 (don't remember exactly), Dassault said we can do 1.3-1.4 or something and Typhoon folks said we can do a full 1.5 or something like that. The ATF program wanted mach 1.5 with an internal load and the F-22 (final version) managed to better that to mach 1.72 (As per the fighters official website - Flight test Data).

The F-35 cannot super cruise as per the F-22 or rather the ATF definition. What it most likely can do is sustain supersonic speeds for 150-200 nm or so which prolongs its supersonic radius with minimal use of afterburners. This was most likely by design as none of the aircraft the F-35 is replacing can go "supersonic" for tactically significant ranges with the sort of load and fuel they carry (on a strike mission). From my understanding of the issue the F-35 requires Burners to overcome the transonic drag and after that initial bump it can sustain with military thrust. Horses for Courses I guess, but the point is that SUPERCRUISE as a term is something that is a descriptive term for a capability specified by one particular service (and that happened to catch on and find its way into marketing materials around the world).

http://www.f22-raptor.com/technology/data.html

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Re: AMCA News and Discussions

Postby Indranil » 17 Oct 2014 02:58

Unfortunately, you are fitting the course for the horse. Anyways, my reply here.

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Re: AMCA News and Discussions

Postby Indranil » 17 Oct 2014 23:08

Cross post from the Kaveri thread:

Specs must be changing. But the numbers will be in the ball park:
Speeds
======
Max speed: 1.8 M
Max speed (Sea level): 1.1 M
Optimal supersonic cruise: 1.3M

Physical size
==========
Length: 17.1 m
Span: 10.5 m (This will change, but 10.5 is a very interesting number)
Height: 4.4m

Performance
==========
Service ceiling: 14 km
Endurance (CAP): 2 hrs
Range: 1000 kms

Weight
=====
MTOW: 23T (I think this has grown to 25 Tons now)
Empty weight: 11 T
Normal T.o. weight: 18.5 T
Internal fuel: 6.5 T
Payload: 5.5 T
Internal carriage: 1.5T (can be released in supersonic flight)

Engine
======
Thrust: 2 X 115 kN with 2D TVC.

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Re: AMCA News and Discussions

Postby Indranil » 18 Oct 2014 01:36

Oh sorry for the confusion. It is radius of action (combat radius): 1000 km (on internal fuel)

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Re: AMCA News and Discussions

Postby srai » 18 Oct 2014 10:31

Marten wrote:So my estimation of size was notnoffnthe mark!?! ;)

Range = 1000km on internal fuel alone! (Before people claim it is being designed/planned with a combat radius of 300 kms).

Who has this 110kN engine waiting for us? We might need to start focusing on parallel development of the Aura.
indranilroy wrote:Oh sorry for the confusion. It is radius of action (combat radius): 1000 km (on internal fuel)


Image

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Re: AMCA News and Discussions

Postby sankum » 18 Oct 2014 13:51

AMCA internal payload of 1.5 t can be expected to be 2*500 kg JDAM+2*150 kg BVR AAM+ 2*100kg SRAAM= 1500KG.

CGI image of AMCA earlier main weapon bay can be estimated to be dimensions of 4m by 1.8m which carry two jdam plus 2 BVRAAM or 5 BVRAAM.

Naval AMCA can be expected to have folded wing dimension of 7.5m.

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Re: AMCA News and Discussions

Postby member_28756 » 21 Oct 2014 09:28

indranilroy wrote: For example the J-31 (another aircraft) of very similar role and dimensions is supposed to be powered by 2 X 100 kN (WS-13A) engines.


Here is a picture of J-31 it looks rather small probably with limited range and load. I hope DRDO will not make the same mistake.


http://zzwave.com/plaboard/uploads/2014 ... 037644.jpg
http://zzwave.com/plaboard/uploads/2014 ... 955176.jpg

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Re: AMCA News and Discussions

Postby Yagnasri » 21 Oct 2014 10:34

Engine may be a major issue once again. Mango man question of course as I know next to none.
Can't we have two Kaveri engines for AMCA? But 2 Kaveri even with present power can be used for the first trench and then to next things. That will make the AC more indigenous and will help further indiginous developments later on.

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Re: AMCA News and Discussions

Postby PratikDas » 21 Oct 2014 10:47

Yagnasri ji, the word is tranche. Ironically, AMCA with 2 Kaveris, if such an aircraft were to materialise, would lift India out of the trenches :)

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Re: AMCA News and Discussions

Postby Yagnasri » 21 Oct 2014 10:55

You mean it is not possible?

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Re: AMCA News and Discussions

Postby PratikDas » 21 Oct 2014 11:11

I wish my opinion mattered, Sir ji :) Thank you for asking though.

For Kaveri to go from 78 kN to 100+ kN, from subsonic test flights alone to supersonic flight, and from the G forces of the subsonic test bed to that of a fighter jet, it seems like there is a lot left to be accomplished. I am all for spending national treasure to make it a reality, but then that's just my wish.

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Re: AMCA News and Discussions

Postby member_20453 » 21 Oct 2014 11:31

^^^^

414 EPE should be the ideal starting match, by then the engine is being made in India under TOT, being the design around it seems like the least risky way forward

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Re: AMCA News and Discussions

Postby srin » 21 Oct 2014 12:57

If they design for 414 EPE and the AMCA weight increases (as it inevitably seems to), you'll have the LCA saga all over again. Design the airplane around slightly overweight, underpowered and fuel hungry Kaveri and they'll see that afterwards, anything will be an improvement.

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Re: AMCA News and Discussions

Postby vishvak » 21 Oct 2014 13:06

OT here. Considering 'ideal' as weasel word, better to design modular engine structure which is a little bigger(can house many different engines) but efficient in aerodynamic and stealth.

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Re: AMCA News and Discussions

Postby Indranil » 21 Oct 2014 17:28

MANNY K wrote:Here is a picture of J-31 it looks rather small probably with limited range and load. I hope DRDO will not make the same mistake.

http://zzwave.com/plaboard/uploads/20141020-u54450ac6d6c037644.jpg
http://zzwave.com/plaboard/uploads/20141019-u544274d43a3955176.jpg


How do you judge from so far and without any other object as reference?

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Re: AMCA News and Discussions

Postby sankum » 22 Oct 2014 06:59

AMCA earlier requirement of 2t internal weapon carriage has been reduced to 1.5 t and internal fuel has gone up from 4t (for MTOW of 20t) to 6.5t (for MTOW of 25t).

For normal take of weight of 18.5t i.e, stealthy A2A mode 6.5 t internal fuel comes to fuel fraction of 35 % i.e comparable to that of F35A or PAKFA. Thus AMCA will have comparable range to that of frontline 5th gen fighters.

In A2G mode internal weapon carriage in stealthy mode TOW comes to 19T and we can expect external payload of 6T for MTOW of 25T in 4 wing stations of 2*1800kg+2*1200kg=6000kg.

Two inward weapon stations should be able to carry mini brahmos of 1500kg.

Rarely MTOW missions will be flown as light PGMs proliferate and heavy weapon load is not a absolute must and even MTOW of 23T will be ok.

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Re: AMCA News and Discussions

Postby abhik » 22 Oct 2014 14:30

^^^
I think the F-35 does carry proportionally more fuel that the AMCA(assuming the above figures). Fuel fraction without any weapons would be 6.5t/(6.5+12t) = ~35.2% compared to 8.4t/(8.4t+13.2t) = ~38.9% for the F-35.

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Re: AMCA News and Discussions

Postby sankum » 22 Oct 2014 14:57

AMCA Empty weight 11t+6.5t internal fuel +1t weapon load for A2A mission=18.5t.

1t air to air missiles consists of 5*160kg BVRAAM+ 2*100kg SRAAM=1000kg.

F35A 13.2T empty weight+ 8.4t internal fuel+ 1.2t weapon load for A2A mission=22.8t.

1.2t air to air missiles consists of 6*160kg BVRAAM+ 2*100kg SRAAM=1160 kg

Fuel fraction comes at 36.84% for F35A and 35.14 % for AMCA.

Roughly ball park figures.

Pilot weight 100kg+ 150kg cannon ammo& chaff/ flare + 350-400kg launcher weights is assumed under the empty weight which can very well be additional to the above figures.

abhik
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Re: AMCA News and Discussions

Postby abhik » 22 Oct 2014 16:16

Thanks for correcting, I thought the empty weight was 12t instead of 11t.

member_28756
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Re: AMCA News and Discussions

Postby member_28756 » 22 Oct 2014 18:34

indranilroy wrote:
MANNY K wrote:Here is a picture of J-31 it looks rather small probably with limited range and load. I hope DRDO will not make the same mistake.

https://imagizer.imageshack.us/v2/841x589q90/673/mSCWMI.jpg
https://imagizer.imageshack.us/v2/426x319q90/910/mALdFf.jpg


How do you judge from so far and without any other object as reference?

OK lets look at a closer pic.. look at the internal weapons bay, the square under the belly, it takes a lot of space and very unlikely it will use out side fuels tanks since it will defeat the stealth design. This is not a big plane most likely the size of a Mig - 29 so carrying both weapons and fuel will be a challenge.

https://imagizer.imageshack.us/v2/883x589q90/633/6bAGJu.jpg


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