LCA News and Discussions

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Re: LCA News and Discussions

Postby Rahul M » 21 Feb 2011 10:17

shiv ji, all those factors considered together are expressed by the value of corner velocity which is defined as the min velocity at which the aircraft achieves its max allowed g-forces. I'm sure you know all this.
to compare the turning performance of two aircraft it is sufficient to consider their corner velocity, lower the corner velocity, better the turning performance.

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Re: LCA News and Discussions

Postby vina » 21 Feb 2011 10:32

shiv wrote:OK - with a loop being controlled flight that is always over stalling speed/AoA - would it be wrong to say that the G one pulls depends on how tight the loop circle is. If the loop is smaller the Gs are higher and vice versa.

With speed being the same, yes. Tighter loop, higher Gs!

If that is true then wouldn't a higher wing loading create more stress on an airframe than a lower wing loading aircraft in a similar sized loop?

Lets say that there are two planes both with weight x tons. One plane has 25% lower wing area than the other , so the wing loading (lift/area) is higher in than the other by 25%! But notice that since both the planes are the same weight X tons, the wings in both the planes produce the same lift of X tons (only then can the plane be level in the air and not rise or fall).

Now if both the plane's airframes are 9 G rated, then both the sets of wings produce 9*X tons max lift and place where the fusleage and wings are joined will have to lift exact those 9X tons!. So to answer your question, the wing loading will have no effect on the fuesage and other structures (wing-fueslage join etc) . The stiffeners inside the wings will experience different stress levels (coz fewer stiffeners inside the smaller wing will have to carry a higher load), but that is really it and nothing very different, coz the wing will have been designed for it.

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Re: LCA News and Discussions

Postby vina » 21 Feb 2011 10:50

shiv wrote:But at one point that tangential velocity will drop below stall speed. The whole idea is that a loop is done at a speed and AoA that is above stall speed.

Yes, if you fly below the minimum speed, you will stall and fall out of the sky in whatever condition! The AoA cannot increase beyond a maximum (which is also the slowest speed the aircraft can fly at). So you will maintain minumum air speed under any condition.

And at any given speed and AoA a higher wing loading should experience more G than a lower one.


G's pulled are not directly related to wing loading as I posted earlier.Gs pulled are limited by the structure of the aircraft, not aerodynamics. However usually a lower wing loading can achieve a higher AoA than a higher loaded wing and the lower wing loading aircraft can turn inside higher wing loaded one.

How is that ?. Foggedabout cambered wings, just take a flat thin plate that is the wing (like in the F-104). Now at 0 AoA, it is a symmetrical airfoil, so zero lift. Now at a slight positive AoA, like say 3 to 4 degs, it generates lift and if you fly that wing fast enough, you generate enough lift to fly and fight and do all that razzmatazz like the F-104. Now suppose AmirKhan Babooze decide that the F-104's wings are "too large" and we want to reduce size by 25%, so all you can do is say Aye Aye Saar, and clip 25% off and to compensate (coz the weight stays same), you will have to increase the AoA of the flat plate wing from the earlier 3 to 4 deg to now 5 to 6 deg (say) to fly level. Problem is that a flat plate has a max AoA of around 15 deg or 16 deg (My madrassa days were long long long ago saar, haven't opened a book since and now do Phynance), so the 25% less wing can do 15/16 - 5 to 6 (ie 8 to 10 deg more) before it stalls and falls out of the sky, while the original wing can do some 12 to 13 deg more before it stalls and falls out of the sky. That effectively means that extra 2 to 3 deg AoA allows you to turn a tighter circle and turn within the plane with a higher wing loading.


So the question I had was that it appears to me that a plane that can achieve a better AoA but has a higher wing loading might not be able to do a tighter loop than another aircraft that has a lower AoA limit but lower wing loading because of G limitations on the airframe. This is what I want to know.


For a given wing, AoA capability and wing loading are related I think (from Madrassa scratching of head from 1st principles) as I just posted. Max G pulled is structure related (for any AoA say just 10 deg, if you fly fast enough, you can pull any high G you want).

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Re: LCA News and Discussions

Postby vina » 21 Feb 2011 11:01

Now , given that basic Madrassa teachings about wings, you ask a kweschun.

Given two planes of nearly same size , nearly same engine (and hence similar power) and nearly same weight , but one plane , plane A has a wing area that is 25% more than the other Plane B and thus has a lower wing loading, which plane will have a higher climb rate, a better turn rate (shorter turn radius) ?.

Good now that you have answered the question. Let us put some numbers. Plane A and Plane B are roughly 13.XX to 14.XX m in length, both weigh 6750 kg empty and Plane A is actually called Tejas and Plane B is called the Gripen, and Tejas has 4XX sqm of wing area and Gripen has 3YY of wing area (roughly 20% more I think) and then ask the sane "objective" folks the same question and what answer do you think the fan boys in the "International" forums will give ? :lol: :lol: :lol:

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Re: LCA News and Discussions

Postby Viv S » 21 Feb 2011 11:15

Dileep wrote:
Viv S wrote:But wouldn't the aircraft eventually gather some speed while falling? The torque on the flaps will eventually push the aircraft back into a neutral AoA position.

An aircraft designed to be aerodynamically stable would eventually recover (if it doesn't reach the ground before that) if left alone. But for an unstable aircraft like Tejas, no action on any of the surfaces would recover it, because the movement is stable in the backward direction.


I don't mean the aircraft would right itself naturally - if the flaps were deployed at maximum deflection, wouldn't the moment of the force acting on them pitch the aircraft down (or up, if the aircraft had stalled in an inverted position).

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Re: LCA News and Discussions

Postby Kanson » 21 Feb 2011 11:50

x-post


To consume fuel more efficiently, a gas turbine engine needs to squeeze air harder before it enters the combustion chamber and turn up the heat.

If only it were so easy.

As the temperature of exhaust gases creeps higher, the next trick is to prevent the high-pressure turbine blades immediately aft of the combustor from melting. Modern turbofans are reaching the limits of metallic survival. Even with blades fashioned from the most robust alloys and systems parasitically diverting airflow into intricate cooling systems, the heat eventually wins.

That is why a 10 November test of a modified General Electric F414 engine is so critical. For the first time, GE has tested a ceramic matrix composite (CMC) turbine blade in a working engine.

Although the 4h-test is only the beginning in a long series, it means CMC receives credit within GE's processes for a technology readiness level of six, meaning that hardware has been tested in an operational environment. It is now eligible to be incorporated in GE's next generation of commercial and military engines.

"As we look to our future engines late this decade or early next decade, we'll be able to get that [CMC] material to a prime, reliable application state," says Dale Carlson, manager of advanced programmes at GE Aviation.

CMC materials have been used in various aerospace applications before. GE incorporates CMC in static parts of the GE/Rolls-Royce Fighter Engine Team F136, the alternate engine for the Lockheed Martin F-35 Joint Strike Fighter.

The recent F414 test, however, represents the first application of CMC material in a rotating engine part, such as a turbine blade. Although part of GE's overall technology roadmap, the test was funded by the US Navy's energy task force. It is being considered for a turbine blade upgrade in the F414, which powers the Boeing F/A-18E/F Super Hornet and the Hindustan Tejas light combat aircraft.

Meanwhile, GE is facing competitive pressure to dramatically improve fuel efficiency rates in future generation of engines. NASA's N+3 concept study, for example, has established a goal to reduce fuel burn by more than 70%.

"You're not going to get there by working coatings [on metallic blades]," says John Kinney, GE's director of advanced programmes.

In the near term, GE is considering CMC materials for its next wave of commercial engines programmes. GE is partnered with Snecma on the CFM International CFM56 turbofan. The replacement Leap-X concept is considering CMC materials for turbine nozzles, but not blades.

On turbine blades, CMC materials are likely to prove attractive on the next generation of widebody engines, such as the powerplant that replaces the Boeing 777's GE90.

The key potential benefit is weight savings. CMC material is lighter than metallic turbine alloys, but it also reduces the weight of the cooling systems required.

"Taking two-thirds out of the weight of a set of turbine blades means you have a lot less turbine structure," Carlson says. "That translates into smaller shafts, smaller bearings. It allows the design to improve all areas of the engine."

GE has estimated that incorporating CMC turbine blades on a GE90-sized engine could reduce the overall weight by about 455kg (1,000lb), which represents about 6% of 7,550kg dry weight of the full-sized GE90-115.

Advanced materials has been identified as one of the key technology investments by NASA and the US military. The latter has launched two programmes - the advanced versatile engine technology and the highly efficient embedded turbine engine - to dramatically improve performance and reduce fuel burn in future engines.

"These are incredible targets," Kinney says. But "you see a pathway to get there. We're marching our way towards those goals."


May 11, 2009 3:51 pm
The Naval Air Systems Command (NAVAIR) has awarded a sole-source, cost-plus-fixed-fee order against a previously issued Basic Ordering Agreement to General Electric Aircraft Engines (GEAE), located in Lynn, MA. The required effort is for the demonstration of new technologies to reduce the Specific Fuel Consumption (SFC) of the F414-GE-400 engine, which powers the F/A-18E/F and E/A-18G aircraft.


Inference than can be made:

1. This CMC in hot section is not some tech demonstrator to take pride as, we too have such technology. It is US Navy funded program and eventually going to be implemented in the engine.

2. Conspicuous by absence is the Gripen program that uses F414. Can we take that only US Navy and Tejas are going to be the beneficiary of this F414 upgrade program ?

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Re: LCA News and Discussions

Postby Indranil » 21 Feb 2011 11:57

To the guys discussing spin ... here the spin is flat spin not role or any other spin.

In a roll in most cases the recovery is simple (though counterintuitive in many cases). Besides, there are some complications in some extreme cases. To understand those cases will be a huge aerodynamics class. One such case was discussed in the Aero India seminar by the American F-18 test pilot. I don't remember correctly but most probably he was discussing CCS at 2000 feet!

Anyways flat spin (the aircraft spins on its belly) is much much more difficult to recover from. You might want to read about it. some aircrafts can't get out of it, no matter what you do.

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Re: LCA News and Discussions

Postby NRao » 21 Feb 2011 13:39

Kanson wrote:x-post


Inference than can be made:

.....................................

2. Conspicuous by absence is the Gripen program that uses F414. Can we take that only US Navy and Tejas are going to be the beneficiary of this F414 upgrade program ?


I would not go that far - yet. GE and Volvo are fused at the hips in certain areas. GE does rely on Volvo for some research. Perhaps not on this particular item. There is enough material out there to indicate that they are cross pollinated. How much of it impacts the MMRCA (present/future) I do not know.

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Re: LCA News and Discussions

Postby Vikram W » 21 Feb 2011 15:38

SaiK wrote:Q: What is that in LCA design that makes it aerodynamically unstable?


The most basic cause of the instability(by design) is the wing shape which is anhedral compared to a Dihedral shape seen on commercial aircrafts and gliders. ( there's also a flat wing style which is seen on entry level trainers). The dihedral tends to bring the aircraft back to stable position in case of a roll , where as the anhedral allows the plane to roll and do other maneuvers.


http://en.wikipedia.org/wiki/Anhedral#Anhedral
http://en.wikipedia.org/wiki/Dihedral_(aircraft)

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Re: LCA News and Discussions

Postby shiv » 21 Feb 2011 16:38

SaiK wrote:Q: What is that in LCA design that makes it aerodynamically unstable?


The instability is in pitch with the CG behind the center of lift causing pitch up.

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Re: LCA News and Discussions

Postby shiv » 21 Feb 2011 19:19

Here is a stall and spin demo on an L-39 simulator
http://www.youtube.com/watch?v=qTPSCfV2wqU

Dramatic F-14 flat spin and crash (good video)
http://www.liveleak.com/view?i=d1a_1251060179

Inverted flat spin and fatal crash
http://www.liveleak.com/view?i=bbe_1250712882

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Re: LCA News and Discussions

Postby Drishyaman » 21 Feb 2011 19:27

SaiK wrote:LCA is not Mig21++ or 3 legged cheetah. It is Mirage2k++ and soon a 4 legged tiger.
from DRDO thread..

+1
I was actually amazed when the ACM told Tejas was Mig-21++.
What Mr. Ajit Doval spoke is the naked truth.

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Re: LCA News and Discussions

Postby shiv » 21 Feb 2011 19:30

Incredible flat spin video and descrption of pilot disorientation
http://www.youtube.com/watch?v=TT1QGG1510w

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Re: LCA News and Discussions

Postby chackojoseph » 21 Feb 2011 20:53

I am cross posting. This could be used as an reference for LCA Naval challenges or understanding.

Eurofighter Naval Version makes debut at Aero India 2011

Image

Image Link

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Re: LCA News and Discussions

Postby Drishyaman » 21 Feb 2011 21:00

Drishyaman wrote:
Tejas MK – II will be lengthened by 0.5 meter just behind the cockpit. Is that being done to accommodate more of the delta wing within “Mach” cone? Can this be assumed as a drag reduction measure?
What else drag reduction measures are taken up (or can be taken up) for reducing the drag in Tejas MK – II?


Can someone answer my query ? If I am wrong, can someone correct me please ?

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Re: LCA News and Discussions

Postby aditya.agd » 21 Feb 2011 21:01

I hope that IAF replaces all mig21 and Mig27 with LCAmk1 and Mig21 Bisons with LCA mk2.

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Re: LCA News and Discussions

Postby Raveen » 21 Feb 2011 21:09

Drishyaman wrote:
Drishyaman wrote:
Tejas MK – II will be lengthened by 0.5 meter just behind the cockpit. Is that being done to accommodate more of the delta wing within “Mach” cone? Can this be assumed as a drag reduction measure?
What else drag reduction measures are taken up (or can be taken up) for reducing the drag in Tejas MK – II?


Can someone answer my query ? If I am wrong, can someone correct me please ?


Better area ruling of the fuselage by lengthening
Last edited by Raveen on 21 Feb 2011 21:24, edited 2 times in total.

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Re: LCA News and Discussions

Postby Drishyaman » 21 Feb 2011 21:16

Raveen wrote:Better area ruling of the fuselage by lengthening

Sir ji, Can you please me a more detailed answer with some more explaination, so that a layman like me can understand.
Also, I had asked 3 questions :)

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Re: LCA News and Discussions

Postby Drishyaman » 21 Feb 2011 21:17

duplicate
Last edited by Drishyaman on 21 Feb 2011 21:18, edited 1 time in total.

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Re: LCA News and Discussions

Postby Lalmohan » 21 Feb 2011 21:18

drishyamanji, please consult a big thick book on supersonic aerodynamics for the answer to your questions!

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Re: LCA News and Discussions

Postby Raveen » 21 Feb 2011 21:20

Drishyaman wrote:
Raveen wrote:Better area ruling of the fuselage by lengthening

Sir ji, Can you please me a more detailed answer with some more explaination, so that a layman like me can understand.
Also, I had asked 3 questions :)



http://en.wikipedia.org/wiki/Area_rule

You can start here and then proceed onto:

Lalmohan wrote:drishyamanji, please consult a big thick book on supersonic aerodynamics for the answer to your questions!


P.S. I thought the increase was 1m in overall length, so I guess the additional .5m would be added past the wing area
Last edited by Raveen on 21 Feb 2011 21:24, edited 1 time in total.

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Re: LCA News and Discussions

Postby Raveen » 21 Feb 2011 21:26

aditya.agd wrote:I hope that IAF replaces all mig21 and Mig27 with LCAmk1 and Mig21 Bisons with LCA mk2.


I am not sure how this post adds constructively to the ongoing discussion, imho brings no value to technical analysis here
Maybe better reserved for the Newbie section

aditya.agd wrote:IAF MUST LEARN FROM INDIAN NAVY, HOW TO PROMOTE LOCAL INNOVATION??


But for this one post I am certain that it belongs in the Newbie section if at all on BR

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Re: LCA News and Discussions

Postby Drishyaman » 21 Feb 2011 21:56

Raveen wrote:
http://en.wikipedia.org/wiki/Area_rule

You can start here and then proceed onto:

Lalmohan wrote:drishyamanji, please consult a big thick book on supersonic aerodynamics for the answer to your questions!


P.S. I thought the increase was 1m in overall length, so I guess the additional .5m would be added past the wing area


Thank you Raveen Ji for the link and the answer.
Lalmahon Ji, Thank you for suggesting me a book, atleast you did not suggest me to go back to college for another 4 yrs UG course or university for another 2 yr PG course :)
My bread and butter would restrict me.

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Re: LCA News and Discussions

Postby sankum » 21 Feb 2011 23:48


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Re: LCA News and Discussions

Postby adarshp » 22 Feb 2011 01:21

^^ Thank you... I have been waiting a long time for a definitive explanation like that...

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Re: LCA News and Discussions

Postby Uttam » 22 Feb 2011 01:26



This article deserves to be posted in full:

When a sword arm is worth it
Ajai Shukla / Bangalore February 22, 2011, 0:49 IST

Myth and reality in the cost of Tejas, the IAF and Navy’s under-development fighter.

The spotlight is swinging on to the Tejas Light Combat Aircraft (LCA). It has been cleared for induction into the Indian Air Force, construction has begun on two squadrons (40 aircraft) and the IAF is picking 40 per cent of the tab for developing a more powerful Tejas Mark II. Now its designers are hitting out at critics who charge the programme has greatly overshot its budget.
P S Subramanyam, head of the Aeronautical Development Agency (ADA), which spearheads the Tejas programme, has given Business Standard detailed financial figures to argue the development cost has remained within budget. ADA also notes the Tejas is significantly cheaper than any comparable fighter.

‘No overshoot’
Slamming some recent media reports that the Tejas was enormously over budget, Subramanyam reveals just Rs 6,051 crore has been spent so far on the fighter, that performed aerobatics at the Aero India show in Bangalore this month. Another Rs 746 crore (of the sanctioned Rs 3,650 crore) has been spent on the naval Tejas, which will fly from the Indian Navy’s future aircraft carriers.

ADA has provided a detailed cost breakdown. The LCA project began in 1983 (the name Tejas only came later), with a preliminary allocation of Rs 560 crore for ‘feasibility studies and project definition’. Subramanyam complains that accusations of cost overruns stem from the misperception that Rs 560 crore was the entire budget for developing the Tejas. In fact, this was merely for defining the project and creating the infrastructure needed for designing, building, testing and certifying a fighter.

Only after a decade of infrastructure building did the design work start, when the ministry of defence (MoD) sanctioned Rs 2,188 crore in 1993 (which included the initial Rs 560 crore). This allocation was to fund the building of two ‘technology demonstrator’ Tejas fighters.

“Within this budget, we flew the Tejas in 2001, and even built two extra Tejas prototypes,” says Subramanyam. “And, that was without any adjustment for inflation or foreign exchange appreciation, though the dollar shot up from Rs 26 to Rs 47 during that period. Our forex component of Rs 873 crore should have been adjusted to Rs 1,642 crore.”

Buoyed by the successful test flight in 2001, the MoD allocated ADA Rs 3,302 crore in November 2001, for Phase-II of the programme. This was to fund a production line and the building and flight-testing of 8 ‘limited series production’ fighters. Phase-II will run till 2012, when the Tejas obtains final operational clearance (FOC) for induction into the IAF as a frontline fighter.

In 2009, with the Tejas flight-testing running slow, ADA obtained an additional Rs 2,475 crore from the government for Phase-II. Subramanyam argues this is not a cost overrun. “The MoD’s allocation of 2001 contained no protection from inflation. If you roll back our annual expenditure to the base year of 2001, we remained within budget,” says the ADA chief.

The IAF is now confident that its Tejas Mk-I will obtain FOC in 2012, within the sanctioned Rs 7,965 crore (Rs 2,188 + Rs 3,302 + Rs 2,475) crore. What remains is to integrate a long-range missile; to enable mid-air refuelling; and to enable the Tejas to fly as slow as 200 kmph.

What we got
Subramanyam argues that this money has not just developed the Tejas, but also India’s ability to build serious fighters. “Consider the aerospace infrastructure that we have built across the country, in key DRDO laboratories, defence PSUs, private industry, academic institutions, and test facilities like the National Flight Testing Centre (NFTC). This has bridged a technology and infrastructure gap of two-three generations,” he says.


WHAT THE MoD WILL PAY
Development Date of
sanction Sanctioned
cost Spent till
Jan 25, ‘11
1. Air Force
(a) Phase-1 (Tejas prototype) Jun 23, ‘93 2,188* 2,188
(b) Phase-2 (Tejas Mark I) Nov 20, ‘01 5,777** 3,859
Sub-total (a & b) 7,965 6,047
(c)Phase-3 (Tejas Mark II) Nov 20, ‘09 2,432 4
Sub-total (a, b & c) 10,397 6,051

2. Navy
(a) Pre-project design Jan 20, ‘99 14 14
(b) Phase-1 (Tejas Mark I) Mar 28, ‘03 1,715*** 732
Sub-total (a & b) 1,729 746
(c) Phase-2 (Tejas Mark 2) Dec 17, ‘09 1,921 Nil
Total (a, b & c) 3,650 746
Grand Total (1 & 2) 14,047 6,797
* Includes Rs 560 crore sanctioned on Aug 22, 1983
** Rs 3,302 crore + Rs 2,475 crore on Jan 20, 2001, and Nov 20, 2009, respectively
*** Rs 949 crore + Rs 766 crore on Mar 28, 2003, and Dec 17, 2009, respectively
Figures in Rs crore

Meanwhile, the naval Tejas will fly within weeks. Significantly different from the IAF version, the naval Tejas must get airborne within 195 metres (the length of an aircraft carrier deck) and withstand the cruel impact of repeated deck landings, in which it must be slammed down precisely where the deck begins. Of the Rs 1,729 crore allocated for the naval Tejas, ADA has spent Rs 746 crore so far.

Encouraged by the success of Tejas Mk-I, the MoD allocated Rs 2,432 crore in 2009 for making the IAF’s fighter even better: developing a Tejas Mk-II, with a newer, beefier, GE-414 engine. Simultaneously, Rs 1,921 crore was sanctioned for the Naval Tejas Mk-II. While the Navy funded 40 per cent of its fighter from the start, the IAF is a new convert, matching the Navy in funding the Tejas Mk-II.

“By 2012, the total development cost for an IAF and a naval Tejas — including a single-seat fighter and a twin-seat trainer variant for each — will be Rs 9,690 crore. Another Rs 4,353 crore will be spent on the Tejas Mark-II, bringing the total cost to Rs 14,047 crore,” says Subramanyam.

The Gripen, a comparable if somewhat more advanced fighter, which Sweden developed during this period, cost US $13.5 billion for 204 fighters, assuming complete tax exemption. A similar number of Tejas fighters entering IAF and Navy service would — provided that HAL holds the Tejas manufacturing price at its current estimate of Rs 180 crore per fighter — have cost India US $11.28 billion.

Given that Sweden entered the Gripen programme with a mature aerospace industry (coming off the successful Viggen programme), India will have built the Tejas, as also an entire aerospace design and manufacturing eco-system, for 17 per cent less money than Sweden paid for the Gripen.

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Re: LCA News and Discussions

Postby disha » 22 Feb 2011 06:39



From the above article:

The IAF is now confident that its Tejas Mk-I will obtain FOC in 2012, within the sanctioned Rs 7,965 crore (Rs 2,188 + Rs 3,302 + Rs 2,475) crore. What remains is to integrate a long-range missile; to enable mid-air refuelling; and to enable the Tejas to fly as slow as 200 kmph.


One of the reasons for high AoA is to ensure that the landing speeds are slow. The airframe can handle high AoA, and all wind tunnel testings might have attested to that, but the envelope might not have been opened up since the airflow to the engine and how the engine behaves is a big unknown. Again that cannot be obtained from wind-tunnel testing, and has to be done only as a real-life testing.

Thanks to Dr. Shiv's birdie, we now know that as a pre-cursor to high AoA testing, the will put in anti-spin parachutes. The engine might flame out at a high AoA and that might result in an un-recoverable spin. Again, the way Tejas is designed, it is difficult to see a situation where the musharaf is pointed to an airflow, since any spin should point the nose back into the wind! However precautions have to be taken.

Now if you want to simulate the lift and drag at different AoA, try this out, you can stick in a straight wing itself and see how it behaves.

http://www.grc.nasa.gov/WWW/K-12/airplane/foil3.html

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Re: LCA News and Discussions

Postby Baldev » 22 Feb 2011 06:57

nothing to do with derby capability but had IAF been asked which BVR missile they want on LCA?
http://livefist.blogspot.com/2011/02/de ... -deal.html

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Re: LCA News and Discussions

Postby Sid » 22 Feb 2011 07:31

Baldev wrote:nothing to do with derby capability but had IAF been asked which BVR missile they want on LCA?
http://livefist.blogspot.com/2011/02/de ... -deal.html


I think it has more to do with integration with radar.

With Israeli MMR on board it is logical that they went go for Derby. Might be others are not so willing to share their missile secrets for integration with MMR.

Some will argue that we have all Indian made codes/hardware in MMR, but it also depends missile company on how much they are willing to share regarding their AAM.

Last I read somewhere, Russians gave IAF/DRDO big headache when India asked for some missile integration.

Baldev
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Re: LCA News and Discussions

Postby Baldev » 22 Feb 2011 07:46

Sid wrote:
Baldev wrote:nothing to do with derby capability but had IAF been asked which BVR missile they want on LCA?
http://livefist.blogspot.com/2011/02/de ... -deal.html


I think it has more to do with integration with radar.

With Israeli MMR on board it is logical that they went go for Derby. Might be others are not so willing to share their missile secrets for integration with MMR.

Some will argue that we have all Indian made codes/hardware in MMR, but it also depends missile company on how much they are willing to share regarding their AAM.

Last I read somewhere, Russians gave IAF/DRDO big headache when India asked for some missile integration.
well if Russians gave headache was there no other missile except R77 and derby?

even in derby case is Israel doing integration for free?

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Re: LCA News and Discussions

Postby Gurneesh » 22 Feb 2011 07:49

Sid wrote:
Baldev wrote:nothing to do with derby capability but had IAF been asked which BVR missile they want on LCA?
http://livefist.blogspot.com/2011/02/de ... -deal.html


I think it has more to do with integration with radar.

With Israeli MMR on board it is logical that they went go for Derby. Might be others are not so willing to share their missile secrets for integration with MMR.

Some will argue that we have all Indian made codes/hardware in MMR, but it also depends missile company on how much they are willing to share regarding their AAM.

Last I read somewhere, Russians gave IAF/DRDO big headache when India asked for some missile integration.


What I am concerned about is that Derby has been reported to not be a good performer and this might end up being an excuse for IAF against LCA. It is another story if IAF wanted Derby.

Sid
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Re: LCA News and Discussions

Postby Sid » 22 Feb 2011 08:00

Russians (IMHO) won't allow R-77 integration with Israeli radar, that leaves us with Mica EM/Meteor. And I am sure EADS is not so eager to allow their integration with MMR either.

Anyways, it should be considered as stopgap measure until Astra matures.

There are not so many AMRAAM out there. Guess which will allow MMR integration.

->AIM-120 (US)
->R77 (Russia)
->Derby (Israel)
->MICA EM (EU)
->Meteor (EU)

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Re: LCA News and Discussions

Postby Rahul M » 22 Feb 2011 08:24

what israeli radar ?

Sid
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Re: LCA News and Discussions

Postby Sid » 22 Feb 2011 08:40

^^Indian radar ji, how can I forget. Just like IN, I am not sure ADA has much choices with AMRAAM.

Just to make sure my guesses are not shot in the dark, here is what little birdie on BR wrote.

LSP-3 is ready to fly and will do very soon (within next 1-2months). LSP-3 has the radar integrated in it. The radar is has the LRDE/HAL antenna, ECIL/BARC developed APL, indigenous power amplifier and indigenous FRP radome.. the rest is all Elta stuff -- all the signal & data processing units, all the software for AA, AG, AS modes and the fire control algorithms come straight out of 2032

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Re: LCA News and Discussions

Postby SaiK » 22 Feb 2011 09:00

That is kind of odd... that we are actually struggling on the signal processing and software on the radar.

Rahul M
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Re: LCA News and Discussions

Postby Rahul M » 22 Feb 2011 09:03

it's a hybrid ji, why make it sound like something it is not ? and the 2032 backend would be replaced in due time.

Sid
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Re: LCA News and Discussions

Postby Sid » 22 Feb 2011 09:21

Yes, its a hybrid Rahul.

But on topic of Derby being selected for LCA, this is one of those denied technologies which comes at a high price (just what Vice Admiral Raman Puri said in link posted on last page).

Everyone knows that Astra is not available. And without AMRAAM LCA wont qualify for FOC. All this news of why Derby being selected will only slow things up for LCA.

Derby is just a interim solution just like MMR backend.

Austin
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Re: LCA News and Discussions

Postby Austin » 22 Feb 2011 10:05

Personally I do not think they would integrate R-77,AMRAAM,MICA etc with Tejas ... it might just end up being expensive and these countries would not allow such integration or might just ask blood money for it.

Right now integration of Derby/Python 5 should just do fine , these two missile have a overlapping kill zone and NEZ , integration of two will just play along quite well , it will make up for some shortcoming in range with high probability of kill and better ECM/Decoy protection.

Once Astra gets developed which should be accelerated as quickly as we can , we will get a AMRAAM C5 class BVR capability and if that comes with with Tejas Mk2 its fine , for Tejas Mk1 Derby/Python and at a later stage integration of Astra should go well.

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Re: LCA News and Discussions

Postby neerajb » 22 Feb 2011 11:00



Wow! PS Subramanyam fights back the DDM. :twisted:
I get this eerie feeling that DRDO/ADA guys go through this forum for motivation/'What to do next' purposes as far as PR is concerned. Distinctly remember Shivji's recent piskological post on how DRDO has withdrawn into it's shell by DDM's constant/irrational criticism of DRDO/PSUs/Desi stuff. Rajat Pandit et al, did the article whir grey matter (if any) in your thick heads?

Cheers....

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Re: LCA News and Discussions

Postby krishnan » 22 Feb 2011 11:10

My comment

Funny, no one complains when crores are wasted in bollywood good for nothing movies. Why? Cause Malika shows her skin?
:P


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