ADA Tejas (LCA) News and Discussions

[Kunal Biswas]

Some Specs :

the above is the mock up of of proposed tejas mk-2

 

[ersakthivel]

 

[ersakthivel]

despite all the obvious diferences still some call it a rip off!!!!!

 

[sayareakd]

despite all the obvious diferences still some call it a rip off!!!!!

it was posted in Pakistani forum so guess who is saying it..........

Since they never made anything by themselves, therefore they have no idea what it takes to develop a fighter.

 

[Kunal Biswas]

Except both are delta wing and Single engine every thing else is different, Only a less informed or some smart-pant could make such a poster or Some Blind Nationalist Pakistani / Chicom ..

 

[Kunal Biswas]

Tejas Pilots' Hall of Fame

 

[Kunal Biswas]

Tejas Pilots' Hall of Fame

 

[Kunal Biswas]

Tejas Pilots' Hall of Fame

 

[ersakthivel]

Tejas Pilots' Hall of Fame

these are he men who made india's aviation history .they all praised that tejas handles very well and especially SUNEET KRISHNA , "who said TEJAS is ours, and whatever we need in it, it is modularly upgradable.

No one said it is mig-21 ++ .They know what they are flying and what they are talking.They all know that tech level of tejas is one of the very best in IAF.

 

[rahulrds1]

An Indian Navy Official told the magazine-Aviation Week, "The naval variant of the LCA will require the F414 Enhanced Performance Engine [EPE-120KN] providing up to 26,500 pounds of thrust, a 20-percent boost."

LCA Navy - IDP Sentinel
India's Naval LCA Flies but Needs More Power | Aviation International News

 

[sesha_maruthi27]

LCA TEJAS must be mass produced and must be used against the enemy jets as defence and some selected numbers should be used as multi role fighters...........

 

[ersakthivel]

An Indian Navy Official told the magazine-Aviation Week, "The naval variant of the LCA will require the F414 Enhanced Performance Engine [EPE-120KN] providing up to 26,500 pounds of thrust, a 20-percent boost."

LCA Navy - IDP Sentinel
India's Naval LCA Flies but Needs More Power | Aviation International News

India has ordered 99 F414-INS6 engines to power Mk2 versions of the Tejas, but they are believed to offer the standard 22,000 pounds of thrust. The prototype and limited series production Tejas Mk1s–including the naval prototype–are powered by GE F404-IN20 engines that produce 17,700 pounds. India ordered 41 of these after development problems with the indigenous Kaveri engine that was supposed to power the LCA.

well this shortfall in power of 5000 pounds between IN20 and 414 normal is the reason for some of the shortfalls of mk-1 compared to mk-2.

good post rahul.

There was a buzz for a long time that NAVAL LCA will need more than the thrust of normal GE-414, since landing gear and arrestor hook arrangement will add more kgs to the empty weight.

Hope that airforce too will go in for this engine,if not initially then atleast in the second engine change ,but the timeframe for the completion of EPE development must be fixed.otherwise it will lead to the delay in mk-2 development. If it's development is linked to future grippen orders and super hornets winning more export orders ,it will be a hazy outlook.

If all the development cost is not dumped on IAF and if a reasonable price along aith concrete timeframe is quoted this engine will be a boon for tejas-mk-II

I forgot where I came across the news.Thats why I was not able to quote the source.Now your post clarifies a lot of misunderstanding,especially many people are saying that airforce has rejected higher powered version of Ge-EPE -414 engine.

Having this engine will give one of the highest thrust to weight ratios to tejas and also improve top speeds beyond mach-2. service ceilng,sustained turn rate,instantaneous turn rate all will improve, fuel carrying capacity and range will also improve.

If this engine is used for the test flighting of AMCA untill the higher powered engine for AMCA gets ready, it will shorten the time frame for development of AMCA.

Also this 120 kn epe can be used as a fall back option in case there are delays in the development of original higher powered engine meant for amca,exactly like PAKFA and J-20/31 programs are doing now.



Anyway we should wait for the confirmation officially before jumping into any conclusion regarding the availability of 120 kn thrust version of ge- 414 - EPE to tejas-mk-II.A few million dollars more per aircraft for this engine is worth the investment.

 

[ersakthivel]

http://-----------------------/threads/light-combat-aircraft-tejas.111/page-3

SOME interesting news on developmental history of GE-414 engines in the above link.

GE F414-GE-INS6 ordered for the IAF mk-2 doesnot have 120 kn thrust.

 

[Defenceindia2010]

it was posted in Pakistani forum so guess who is saying it..........

Since they never made anything by themselves, therefore they have no idea what it takes to develop a fighter.

RIP-OFF'' an assessment coming from beggars who use cheap Chinese rip-off's of Soviet now Russian and Israeli designs. The comment's on Pakistani forums are nothing more than public display of (Marshal Mental Mentality) :der:, a nation which is unable to make durable bicycler parts is commenting on a aircraft which has taken a better part of 2 decades in planning, conceptualization, prototyping, testing, not to mention the vast knowledge which has been created as a result of the aircraft. The induction may have taken time but self reliance is better than dependence.

 

[ersakthivel]

Earlier this year, the F404-GE-IN20 was trial-installed in Light Combat Aircraft (LCA) as part of final evaluations toward flight-testing, scheduled for mid-2007. The F404-IN-20 engine has generated more than 19,000 pounds (85 kN) uninstalled thrust and has completed 330 hours of Accelerated Mission testing, which is the equivalent of 1,000 hours of flight operation.

The F404-GE-IN20 succeeds F404-F2J3 development engines used for nearly 600 flights, cumulatively covering eight engines.

Based on the F404-GE-402, the F404-GE-IN20 is the highest rated F404 model and includes a higher-flow fan, increased thrust, a Full Authority Digital Electronic Control (FADEC) system, single-crystal turbine blades and a variety of single-engine features.

The F404 fighter engine family is one of the most successful in military aviation history. More than 4,000 F404 engines power a number of combat aircraft flown by the United States Air Force, Navy and Marine Corps, plus countries throughout Europe, Asia and Africa.


the F404-F2J3 that is being used in LSPs and PVs has thrust rating of only 18,300 pounds.

The reason LCA tejas LSPs and PVs are stuck with mach-1.6 at high altitude,and are able to achieve mach 1.2 at sea level , only in a dive from a height of 4km ,and has only 22 degree AOA, and restricted 6Gs is,

The LSP s are operating only at a restricted flight envelope of 85 percent on the thrust of 18,300 pounds from F404-F2J3 engine.

But the SPs (serial production) will operate on 100 percent fully opened flight envelope with 19000 pounds of thrust. from Ge-F404-IN20 engine.

So the Tejas in SP version will have much better specs than the LSps and PV versions which have lesser powered engines.

And mk-2 will have much higher thrust at 22000 pounds.

The option of 26000 pounds in EPE version is also available.




The F404-1N20 selected for initial tejas mk-1 has ------- 19,000 (LCA MK1)

Often it is said GE F414-INS6 ordered for LCA Mk2 is same as GE F414-EPE.


Thrust of GE F404 variants in pounds

F404-1N20 > 19,000 (LCA MK1)

F404-F2J3 = 18,300 (LCA-TD)--Running on the tech demos,prototype vehicles(PV),Limited series production (LSP) versions of tejas mk-1.

F404/RM12 = 18,100 (Gripen)

F404-402 = 17,700
F404-400 = 16,000

SO it is bullshit to compare TEJAS to old mig-21s and no performance shortfall exists in reality.IAF is getting a world class 4th gen plane to replace all the outdated four hundred mig-21s,mig-27s and jaguars that are in IAF .And it can perform closer to mirage in mk-1 and exceed mirage in mk-2 version with 120 km range radars and BVR missiles.

 

[Godless-Kafir]

Then why every fighter manufacturer like LM , Boeing , Sukhoi , Dassault ,EADS ,chengdu,SAAB are building low wing loading fighters? 4th gen or 5th gen?
Why are they not building high wing loading energy retaining fighters like F-16 ,which has a wing loading of 400 plus kg/sq.met.?

I would think the F-16 had a lot of wing area. Any way after the end of cold war dedicated fighters are no longer required, today AFs have moved to Multi-roll fighters which can be a combination of many requirments.

 

[ersakthivel]

I would think the F-16 had a lot of wing area. Any way after the end of cold war dedicated fighters are no longer required, today AFs have moved to Multi-roll fighters which can be a combination of many requirments.

if the wing design was wrong ADA had a chance to correct it for mk-2.if canards were needed ADA would have added them on mk-2.
Instead canards have not been added on mk-2 and the wing area of tejas-mk-2 will increase to retain the same low wing loading.
But mk-2 will have mach-2 top speeds in high altitude and 1.2 mach at sealevel same as any high wing loading fighter in IAF.

So I think ADA has not thought that some thing was wrong with their low wing loading design.

Delta wing - Wikipedia, the free encyclopedia

The primary advantage of the delta wing is that, with a large enough angle of rearward sweep, the wing's leading edge will not contact the shock wave boundary formed at the nose of the fuselage as the speed of the aircraft approaches and exceeds transonic to supersonic speed.


The rearward sweep angle vastly lowers the airspeed normal to the leading edge of the wing, thereby allowing the aircraft to fly at high subsonic, transonic, or supersonic speed, while the over wing speed of the lifting air is kept to less than the speed of sound.

The delta plan form gives the largest total wing area (generating useful lift) for the wing shape, with very low wing per-unit loading, permitting high maneuverability in the airframe. As the delta's platform carries across the entire aircraft, it can be built much more strongly than a swept wing, where the spar meets the fuselage far in front of the center of gravity.


Generally a delta will be stronger than a similar swept wing, as well as having much more internal volume for fuel and other storage.

Another advantage is that as the angle of attack increases, the leading edge of the wing generates a vortex which energizes the flow, giving the delta a very high stall angle. [citation needed] A normal wing built for high speed use is typically dangerous at low speeds, but in this regime the delta changes over to a mode of lift based on the vortex it generates.


The disadvantages, especially marked in the older tailless delta designs, are a loss of total available lift caused by turning up the wing trailing edge or the control surfaces (as required to achieve a sufficient stability) and the high induced drag of this low-aspect ratio type of wing. This causes delta-winged aircraft to 'bleed off' energy very rapidly in turns, a disadvantage in aerial maneuver combat and dogfighting.

With newer compound delta, and a part of the delta wing with lower sweep angle , mimics the old swept swings properties to off set the disadvantege, and postpones the onset of stall.e-x F-16 XL, TEJAS

Canards also serve the same purpose of creating helpful energising vortices over delta wing and delays the onset of stall. e-x grippen rafale,typhoon

Fly by wire software also helps the pilot for carefree flying.

This following link beautifully explains the resurgence of low wing loading delta form.
http://www.century-of-flight.net/Aviation history/evolution of technology/Delta Wings.htm

By 1953, Convair's engineers had developed the YF-102 Delta Dagger, a radical design that lacked a horizontal tail and featured a large, sharply swept delta wing. Wind tunnel tests of small-scale models indicated that the aircraft could accelerate through Mach 1 (the speed of sound) with relative ease, rather than "punching" through it like earlier experimental planes that had to burn a lot of fuel to go faster than Mach 1. However, the first prototype unexpectedly encountered immense drag as it approached Mach 1. This so-called "transonic" region presented a major problem for the aircraft.

Near the same time, Richard T. Whitcomb, an aeronautical scientist at the National Advisory Committee for Aeronautics (NACA), was studying transonic drag. Whitcomb developed what he called the "supersonic area rule." This theory stated that aircraft that would fly at supersonic speed should increase in cross-sectional area from a pointed nose.


Anything that protruded into the air stream, such as the canopy over the cockpit, wings, or tail, should be accompanied by a reduction in cross-section elsewhere. In 1954, Whitcomb, who was then only 33-years old, was awarded the prestigious Collier Trophy for this contribution to aeronautics.

Convair's designers quickly applied the supersonic area rule to a new aircraft, the YF-102A, pinching the fuselage near its mid-point to give it a slightly hourglass (or Coke-bottle) appearance. This was a compromise for an existing aircraft; later airplanes included the area rule in their designs in much less obvious ways. When the first YF-102A with this new design took flight, it easily accelerated through Mach 1.


During the 1950s the delta wing was used on several aircraft that had a need for speed, including the B-58 Hustler and the cancelled XB-70 Valkyrie bomber. The Soviet Union used a delta wing for its failed Tu-144 supersonic passenger jet, and for its famed MiG-21, one of the most widely-used fighter jets of the Cold War. The French also adopted the delta for its successful Dassault Mirage III.

The two most famous current aircraft to use the delta wing are the Concorde and the Space Shuttle. The Concorde's delta wing made the plane's sustained cruising speed of Mach 2 possible. The Space Shuttle's wing, known as a "cranked delta" because the leading edge of the wing has a slight bend near its midpoint, is used for a different purpose. The Space Shuttle originally had what was known as a "high cross-range" requirement, which was the ability to glide for thousands of miles to either side of its flight path when landing. Conventional straight wings did not provide enough lift at high speeds and altitudes to achieve this type of range, and so the large delta wing was necessary.

While delta wings are critical to achieving high lift for supersonic flight, they also have a number of disadvantages for less high-performing aircraft. They require high landing and takeoff speeds and long takeoff and landing runs, are unstable at high angles of attack, and produce tremendous drag when "trimmed" to keep the plane level.

Of these disadvantages, pilots and designers usually consider the high landing and takeoff speeds the most important because they make flying the plane dangerous. Indeed, when the Concorde had its first ever crash in 2000, after two decades of safe operations, the high-speed takeoff was a factor in this terrible accident, for the plane's high ground speed before becoming airborne placed major stress upon the aircraft's tires, which exploded upon striking an object on the runway.

By the 1980s, except for the Concorde and Space Shuttle, the delta wing appeared headed for obsolescence. Its drawbacks made it unattractive and changes in fighter warfare reduced the requirement for sustained supersonic speed.

Few aircraft spend much time travelling at high supersonic speeds because it burns so much fuel, rendering the delta wing, which is primarily useful for supersonic flight, less attractive. But the computer and an additional flight control device called the canard and compound or cranked delta forms have rescued the delta wing from obsolescence.

Computer-controlled "fly-by-wire" flight control systems have allowed designers to compensate for some of the delta wing's poor control qualities. Canards are small horizontal fins (or small wings) mounted on the fuselage in front of an aircraft's main wings to provide greater control, particularly during high angles of attack. When they are part of a delta-wing aircraft, they improve its stability and manoeuvrability.

Several aircraft appeared in the 1980s and 1990s that incorporated both delta wings and canards. The latest delta-wing aircraft are the Swedish JAS 39 Grippen, the Dassault Rafale naval fighter (designed to be launched from the French aircraft carrier Charles de Gaulle), the Indian Light Combat Aircraft, or LCA, and the Eurofighter Typhoon.


The Typhoon, which had its first flight in the mid-1990s, is a joint European effort (Britain, Germany, Italy and Spain, with France withdrawing early) to develop an advanced fighter to replace a number of different aging aircraft in their air forces. Thus, the delta wing, which seemed destined for obsolescence, has gained a new lease on life.

A careful reading of the above link will help us all understand why tejas has such large low wing loading delta wing.

 

[Decklander]

Anyone who thinks that F414INS6 will be same as F414-400 is wrong. The EPE variant has only six HP stages as it has new wide swept fan. This has allowed them to increase thrust without the need of increasing its inlet diameter. F414-standard name of engine, IN-Indian variant, S6-six stage compressor. Of all F414 variants only EPE model has six stages and it was already tested to TRL-6 stage.
This variant will be delivered with full EPE power but derated to 108KN for IAF and a special bump feature for 118KN thrust for IN.

 

[ersakthivel]

Anyone who thinks that F414INS6 will be same as F414-400 is wrong. The EPE variant has only six HP stages as it has new wide swept fan. This has allowed them to increase thrust without the need of increasing its inlet diameter. F414-standard name of engine, IN-Indian variant, S6-six stage compressor. Of all F414 variants only EPE model has six stages and it was already tested to TRL-6 stage.
This variant will be delivered with full EPE power but derated to 108KN for IAF and a special bump feature for 118KN thrust for IN.

Thanks for the post.

So is it official mk-2 will have F414INS6 engine with 108 kn?

Then it will be a huge boost in performance level for mk-2.

Can FBW software use the bump feature in emergency close combat fights with full 120 kn thrust?
Please clarify.

 

[ersakthivel]

Anyone who thinks that F414INS6 will be same as F414-400 is wrong. The EPE variant has only six HP stages as it has new wide swept fan. This has allowed them to increase thrust without the need of increasing its inlet diameter. F414-standard name of engine, IN-Indian variant, S6-six stage compressor. Of all F414 variants only EPE model has six stages and it was already tested to TRL-6 stage.
This variant will be delivered with full EPE power but derated to 108KN for IAF and a special bump feature for 118KN thrust for IN.

Thanks for the post.

So is it official mk-2 will have F414INS6 engine with 108 kn?

Then it will be a huge boost in performance level for mk-2.

Can FBW software use the special bump feature with full 120 kn thrust in emergency close combat fights ?
Please clarify.