What's new

Tejas(LCA)- Setting the record straight

I couldn't understand the logic how you find these two planes are indentical?? :undecided:

Both have wings, missiles, and engines. Most important both are planes. So its quiet easy to say it is copy. You Indian don't have good IQ and not accepting the IQ of Chini. :rofl:
 
Chapter 3: Kaveri

Like the river it is named after this engine and its story also seems to stretch on as far as the eye can see.

This is the most important and difficult part of the entire and LCA project.

To develop and then manufacture a fully indigenous engine. for use in the Military aircraft.

an ambition that has been riddled with years of delay. Failure to create a fully realized version of the designed engine has been the single greatest contributor to the Delay of the LCA programe.

A little summary for our less informed members.
In 1986, the Indian Defence Ministry's Defence Research and Development Organisation (DRDO) was authorized to launch a programme to develop an indigenous powerplant for the Light Combat Aircraft. It had already been decided early in the LCA programme to equip the prototype aircraft with the General Electric F404-GE-F2J3 afterburning turbofan engine, but if this parallel program was successful, it was intended to equip the production aircraft with this indigenous engine.

The DRDO assigned the lead development responsibility to its Gas Turbine Research Establishment (GTRE), which had some experience in developing jet engines. It had developed the GTX37-14U afterburning turbojet, which first ran in 1977, and was the first jet engine to be designed entirely in India. A turbofan derivative, the GTX37-14UB, followed. The GTRE returned to turbojet technology with the greatly redesigned, but unsatisfactory, GTX-35.

For the LCA programme, the GTRE would again take up a turbofan design which it designated the GTX-35VS "Kaveri" (named after the Kaveri River). Full-scale development was authorised in April 1989 in what was then expected to be a 93-month programme projected to cost 382 crores (nearly US$82 million at the time).

Contrary to popular belief this was not India's first ever engine.

Design and development of a "demonstrator" gas turbine engine—GTX 37-14U—for fighter aircraft. Performance trials commenced in 1977 and the "demonstrator phase" was completed in 1981. The GTX 37-14U was "configured" and "optimized" to build a "low by-pass ratio jet engine" for "multirole performance aircraft. This engine was dubbed GTX 37-14U B.

However the GTRE GTX-35VS Kaveri, would be the country's most advanced and capable engine.

But the Engine more than any other, has had the failure tag attached to it, because frankly the deadline has long passed and there is nothing to show for it or is there.


Lets examine what Kind of engine the Kaveri really is.

Design

The Kaveri is a low-bypass-ratio (BPR) afterburning turbofan engine featuring a six-stage core high-pressure (HP) compressor with variable inlet guide vanes (IGVs), a three-stage low-pressure (LP) compressor with transonic blading, an annular combustion chamber, and cooled single-stage HP and LP turbines. The development model is fitted with an advanced convergent-divergent ("con-di") variable nozzle, but the GTRE hopes to fit production Tejas aircraft with an axisymmetric, multi-axis thrust-vectoring nozzle to further enhance the LCA's agility. The core Turbojet engine of the Kaveri is the Kabini, named after the Kabini River (which is a tributary of the Kaveri river).

The general arrangement of the Kaveri is very similar to other contemporary combat engines, such as the Eurojet EJ200, General Electric F414, and Snecma M88. At present, the peak turbine inlet temperature is designed to be a little lower than its peers, but this is to enable the engine to be flat-rated to very high ambient temperatures. Consequently, the bypass ratio that can be supported, even with a modest fan pressure ratio, is only about 0.16:1, which means the engine is a "'leaky' turbojet" like the F404.

The Kaveri engine has been specifically designed for the demanding Indian operating environment, which ranges from hot desert to the highest mountain range in the world. The GTRE's design envisions achieving a fan pressure ratio of 4:1 and an overall pressure ratio of 27:1, which it believes will permit the Tejas to "supercruise" (cruise supersonically without the use of the afterburner). The Kaveri is a variable-cycle, flat-rated engine and has 13% higher thrust than the General Electric F404-GE-F2J3 engines equipping the LCA prototypes.

Plans also already exist for derivatives of the Kaveri, including a non-afterburning version for an advanced jet trainer, and a high-bypass-ratio turbofan based on the Kabini core. Another concept being considered is an enlarged version of the Tejas with two engines fitted with fully vectoring nozzles, which might make the vertical tail redundant (the Tejas has no horizontal tail).

An indigenous Full-Authority Digital Engine Control (FADEC) unit, called Kaveri Digital Engine Control Unit (KADECU) has been developed by the Defence Avionics Research Establishment (DARE), Bangalore. The Combat Vehicles Research and Development Establishment (CVRDE) of Avadi was responsible for the design and development of the Tejas aircraft-mounted accessory gear box (AMAGB) and the power take-off (PTO) shaft.

A lot of money the largest chunk of the LCA programe in fact and time has gone into trying to create the GTX-35VS Kaveri.

suffice to say things did not go according to plan.

it is known that the Kaveri has had a tendency to "throw" turbine blades, which required securing blades from SNECMA (as well as digital engine control systems).

Continuing development snags with the Kaveri resulted in the 2003 decision to procure the uprated F404-GE-IN20 engine for the eight pre-production Limited Series Production (LSP) aircraft and two naval prototypes. The ADA awarded General Electric a US$105 million contract in February 2004 for development engineering and production of 17 F404-IN20 engines, delivery of which is to begin in 2006.

In mid-2004, the Kaveri failed its high-altitude tests in Russia, ending the last hopes of introducing it with the first production Tejas aircraft.This unfortunate development led the Indian Ministry of Defence (MoD) to order 40 more IN20 engines in 2005 for the first 20 production aircraft, and to openly appeal for international participation in completing development of the Kaveri. In February 2006, the ADA awarded a contract to SNECMA for technical assistance in working out the Kaveri's problems. At that time, the DRDO had hoped to have the Kaveri engine ready for use on the Tejas by 2009-10.

The Kaveri program has attracted much criticism due to its ambitious objective, protracted development time, cost and time overruns, and the DRDO's lack of clarity and openness in admitting problems. Much of the criticism of the LCA program has been aimed at the Kaveri and Multi-Mode Radar programs.

There has been much criticism of the degree of realism in the DRDO's planning schedules for various elements of the LCA programme, most particularly for the Kaveri development effort. France's SNECMA, with over half a century of successful jet engine development experience, took nearly 13 years to bring the Rafale fighter's M88 engine to low-volume production after bench testing had begun; a similar timespan for the less-experienced GTRE would see Kaveri production beginning no earlier than 2009.

Another criticism has been DRDO's reluctance to admit problems in the engine and its resistance to involve foreign engine manufacturers until the problems became too large to handle.

Lets face it, if this didn't happen, then the LCA would have been inducted already and i would not be typing this post.

This is where LCA program lets us down. where many of its problems arose. Its like giving birth to a baby with its Heart(engine) and Brain(radar) not fully functioning. You could see how that could be interpreted. well as a dead(failure)

BUT its isn't a baby, The LCA is machine and in machines parts can be replaced(as was the case with the Radar), and parts can be mended(engine).

So it was that in recent years, DRDO has been hard at work tryig to get the dam thing completed.

The Kaveri is still in development, and reports indicate that it will be ready to fly by 2009. Testing and certification for use on the Tejas is expected to take some more time after that. Till then, the first two squadrons of Tejas will be powered by the GE404 engine.

Scientific Advisor to Defence Minister M Natarajan said nearly 90 to 93 per cent of the expected performance had been realised and the government had recently floated an expression of interest to seek partners to move the programme further

DRDO has reportedly been able to develop single crystal blades, which represent a major technological achievement for engine development. Production and integrating this technology into the engine is expected to take some more time.

Kaveri has already undergone 1,700 hours of tests and has been sent twice to Russia to undergo high-altitude tests for which India has no facility. The engine is also being tested to power the next generation of Unmanned Aerial Vehicles.

In September 2008, it was announced that the Kaveri would not be ready in time for the Tejas, and that an in-production powerplant would have to selected. Development of the Kaveri by the GRTE would continue for other future applications.

It was announced in November 2008 that the Kaveri engine will be installed on LCA by December 2009, apparently for tests only.

"Scientific Advisor to Defence Minister M Natarajan said nearly 90 to 93 per cent of the expected performance had been realised"

well that's a whole lot better then the alternative of using another foreign engine.

But enough of all this lets just get some cold hard figures on the engine. as well as comparison to other engins the IAF also uses or could use.

Specification (GTX-35VS Kaveri)

General characteristics

* Type: Afterburning turbofan
* Length: 137.4 in (3490 mm)
* Diameter: 35.8 in (910 mm)
* Dry weight: 2,427 lb (1,100 kg) [Production model goal: 2,100 lb (950 kg)]

Components

* Compressor: two-spool, with low-pressure (LP) and high-pressure (HP) axial compressors:
o LP compressor with 3 fan stages and transonic blading
o HP compressor with 6 stages, including variable inlet guide vanes and first two stators

* Combustors: annular, with dump diffuser and air-blast fuel atomisers
* Turbine: 1 LP stage and 1 HP stage

Performance

* Maximum Thrust:
o Military thrust (throttled):11,687 lbf (52.0 kN) [Goal: 13,500 lbf (60.0 kN) ]
o Full afterburner:18,210 lbf (81.0 kN) [Goal: 20,200 lbf (90.0 kN)]
* Specific fuel consumption:
o Military thrust: 0.78 lb/(lbf•h) (79.52 kg/(kN·h))
o Full afterburner: 2.03 lb/(lbf•h) (207.00 kg/(kN·h))
* Thrust-to-weight ratio: 7.8:1 (76.0 N/kg)

Engine cycle

* Airflow: 172 lb/s (78.0 kg/s)
* Bypass ratio: 0.16:1 [Goal: Between 0.3:1 & 0.4:1]
* Overall pressure ratio: 21.5:1 [Goal: 27:1]
* LP compressor pressure ratio: 3.4:1 [Goal: 4:1]
* HP compressor pressure ratio: 6.4:1
* Turbine entry temperature: 2,218-2,601 °F (1,214-1,427 °C; 1,487-1,700 K) [Goal: 3,357 °F (1,847 °C; 2,120 K)]

The Saturn AL-31 is a family of military turbofan engines. It was developed by Lyulka, now NPO Saturn, of Russia (former Soviet Union), originally for the Sukhoi Su-27 'Flanker' air superiority fighter. It produces a total thrust of 123 kN (27,600 lb) with afterburning in the AL-31F, 137 kN (30,800 lb) in the AL-31FM (AL-35F) and 142 kN (32,000 lb) in the AL-37FU variants. Currently it powers all Flanker derivatives and the Chengdu J-10 multirole jet fighter which has been developed in China.

Specifications (AL-31F)
General characteristics

* Type: Two-shaft afterburning turbofan
* Length: 4990 mm
* Diameter: 905 mm inlet; 1280 mm maximum external
* Dry weight: 1570 kg(Russia standard), 1800 kg(French standard)

Components

* Compressor: 4 fan and 9 compressor stages
* Bypass ratio: 0.59:1
* Turbine: 2 single-staged turbines

Performance

* Maximum Thrust:
o 16,754 lbf (74.5 kN) military thrust
o 27,557 lbf (122.6 kN) with afterburner
* Specific fuel consumption:
o Military thrust: 0.67 lb/(lbf·h)
o Full afterburner: 1.92 lb/(lbf·h)
* Thrust-to-weight ratio: 8 (Russia standard), 7 (French standard)

Specification (F404-GE-402)
General characteristics

* Type: Afterburning turbofan
* Length: 154 in (3,912 mm)
* Diameter: 35 in (889 mm)
* Dry weight: 2,282 lb (1,036 kg)

Components

* Compressor: Axial compressor with 3 fan and 7 compressor stages
* Bypass ratio: 0.34:1
* Turbine: 1 low-pressure and 1 high-pressure stage

Performance

* Maximum Thrust:
o 11,000 lbf (48.9 kN) military thrust
o 17,700 lbf (78.7 kN) with afterburner
* Overall pressure ratio: 26:1
* Specific fuel consumption:
o Military thrust: 0.81 lb/(lbf·h) (82.6 kg/(kN·h))
o Full afterburner: 1.74 lb/(lbf·h) (177.5 kg/(kN·h))
* Thrust-to-weight ratio: 7.8:1 (76.0 N/kg)

The SNECMA M53 is an afterburning turbofan engine developed for the Dassault Mirage 2000 fighter by Snecma. The engine is in service with different air forces, including the latest Mirage 2000-5 and 2000-9 multirole fighters.

Variants

* M53-5 - powered initial Mirage 2000C models
o Dry thrust: 54.0 kN (5,500 kgp / 12,230 lbf)
o Afterburning thrust: 86.3 kN (8,800 kgp / 19,400 lbf)

* M53-P2 - powered later Mirage 2000C models and used to upgrade earlier models [2]
o Dry thrust: 64.7 kN (6,600 kgp / 14,500 lbf)
o Afterburning thrust: 95.1 kN (9,700 kgp / 21,400 lbf)

[edit] Specifications (M53-P2)
General characteristics

* Type: Afterburning single-shaft turbofan
* Length: 5,070 mm (199.60 in)
* Diameter: 796 mm (31.33 in) inlet
* Dry weight: 1,515 kg (3,340 lb)

Components

* Compressor: 8-stage axial compressor
* Bypass ratio: 0.36:1
* Turbine: 2-stage axial turbine

Performance

* Maximum Thrust:
o 64 kN (14,300 lbf) military thrust
o 95 kN (21,384 lbf) with afterburner
* Overall pressure ratio: 9.8:1
* Specific fuel consumption:
o 0.90(kg/daN.h)Dry engine thrust
o 2.10(kg/daN.h) military thrust
* Thrust-to-weight ratio: 6.5

The Snecma M88 is an afterburning turbofan engine developed by Snecma for the Dassault Rafale fighter.

Specifications
General characteristics

* Type: twin-shaft, bypass turbofan engine
* Length: 3531 mm (139 in)
* Diameter: 698.5 mm (27.5 in) inlet
* Dry weight: 897 kg (1,978 lb)

Components

* Compressor: 6-stage
* Bypass ratio: 0.30:1
* Turbine: 2 single-staged turbines

Performance

* Maximum Thrust:
o 11,250 lbf (50.04 kN) military thrust
o 17,000 lbf (75.62 kN) with afterburner
* Overall pressure ratio: 24.5:1
* Turbine inlet temperature: 1,850K (2,871 °F)
* Fuel consumption: dry 0.80 kg/(daN·h)
* Thrust-to-weight ratio: approx. 8.5:1


well be examining these specifications you can see where the current Kaveri and Project goal Kaveri stand. Performance wise.

upon examine the figures you will find the Kaveri to be in fact a Highly capable engine in its own right.
And it has to be given the fact that the there so many uses for it.

Plans are also already under way for derivatives of the Kaveri, including a non-afterburning version for an advanced jet trainer and a high-bypass-ratio turbofan based on the Kaveri core, named as Kabini.

* GTX-35VS Kaveri:
o HAL Tejas (planned for production models)
o HAL Medium Combat Aircraft (conceptual)
o Unmanned Aerial Vehicles

Derivatives:

* The Indian government plans to adapt and further develop the Kaveri engine design and technology to create a gas-turbine powerplant for armoured fighting vehicles such as the Arjun tank.

* Kaveri Marine Gas Turbine (KMGT), a recently developed derivative of the GTX-35VS Kaveri engine for ships.

The IAF has stated interest in Making the GTX-35VS Kaveri and its variants the standard engines for all its aircraft. Given that it realizes all its project goals.
To that end
Dassault has also offered to fit the Kaveri engine into the Rafale, which, if chosen, which would greatly improve commonality with the Tejas aircraft that will enter service into the IAF by 2010.

The Kaveri is realy not about just the LCA anymore, All three branches of the Indian Military have a stake in it.

Quite frankly given the Huge support the Engine has garnered, what should have been a failed venture has been brought back from the brink of defeat to well a positive outcome.

The DRDO, however, currently hopes to have the Kaveri engine ready for use on the Tejas by 2010.

This program has survived literally fueled by hope(as well as quarter of a billion dollars), who knows may be, we may still be surprised.

Chapter 4: The Battle royale
 
Last edited:
I couldn't understand the logic how you find these two planes are indentical?? :undecided:

Both have engine, wings, can carry weapons, can't you see all these similarities. on top of that delta wing. :rofl: :rofl:

Yara, people cries foul when you use words like copy, identical, imitate etc. for their tech. :cry: but shamelessly use them to show their superbia :woot:

so it's better to ignore them :cheers: Naaaa never do that :disagree: :devil:
 
788fd6daf8258133eb93d5f6b3c78bc9.jpg



0fa51e2e0abde7168c2ae4b9972badba.jpg



c78a2f6c748d0c3fc91c754d098a3d86.jpg



b74142bbc89bfd10ded424acf08db1c4.jpg



kaveri-marine

7e73ec6930d3cda9c08758a7d240daf6.jpg
 
Chapter 3: Kaveri

"Scientific Advisor to Defence Minister M Natarajan said nearly 90 to 93 per cent of the expected performance had been realised"


well be examining these specifications you can see where the current Kaveri and Project goal Kaveri stand. Performance wise.

Specification (GTX-35VS Kaveri)


Performance

* Maximum Thrust:
o Military thrust (throttled):11,687 lbf (52.0 kN) [Goal: 13,500 lbf (60.0 kN) ]
o Full afterburner:18,210 lbf (81.0 kN) [Goal: 20,200 lbf (90.0 kN)]
* Specific fuel consumption:
o Military thrust: 0.78 lb/(lbf•h) (79.52 kg/(kN·h))
o Full afterburner: 2.03 lb/(lbf•h) (207.00 kg/(kN·h))
* Thrust-to-weight ratio: 7.8:1 (76.0 N/kg)

Specification (F404-GE-402)

Performance

* Maximum Thrust:
o 11,000 lbf (48.9 kN) military thrust
o 17,700 lbf (78.7 kN) with afterburner
* Overall pressure ratio: 26:1
* Specific fuel consumption:
o Military thrust: 0.81 lb/(lbf·h) (82.6 kg/(kN·h))
o Full afterburner: 1.74 lb/(lbf·h) (177.5 kg/(kN·h))
* Thrust-to-weight ratio: 7.8:1 (76.0 N/kg)

it seems the problem with Kaveri is only related to its performance which is about 90-93% to its designed goal as per Scientific Advisor to Defence Minister M Natarajan.
but i failed to understand it after comparing Kaveri spec with F404-GE spec in terms of performance. Isn't Kaveri's current performance better than F404-GE? then why LCA is now flying with F404-GE not Kaveri? :what:
 
it seems the problem with Kaveri is only related to its performance which is about 90-93% to its designed goal as per Scientific Advisor to Defence Minister M Natarajan.
but i failed to understand it after comparing Kaveri spec with F404-GE spec in terms of performance. Isn't Kaveri's current performance better than F404-GE? then why LCA is now flying with F404-GE not Kaveri? :what:

As far as I know, Kaveri is still under development.
 
it seems the problem with Kaveri is only related to its performance which is about 90-93% to its designed goal as per Scientific Advisor to Defence Minister M Natarajan.
but i failed to understand it after comparing Kaveri spec with F404-GE spec in terms of performance. Isn't Kaveri's current performance better than F404-GE? then why LCA is now flying with F404-GE not Kaveri? :what:

The Kaveri engine only this year has become operational. With no flaws in design.

The IAF being ever uncompromising , wants further trials and tweaking of the engine. Till then they have the GE-404 which has been tried and tested with over 1000 flights on tejas. Inducting the desperately need first squadron with an Imported engine that was already bought 2 years prior, was really the quickest step forward.

But the major issue is that The Kaveri weighs more then it should about 200-400 Kg more.
And LCA also weighs more then it was supposed to.
Combined it was felt the Increased weight would effect Payload size.
For long range missions.

so, in order for the project to move forward.
The engine needs to either produce more trust or slim down.
Or preferably a little bit of both.

That's why India wants to bring Schema in to help with the Engine work. They want to Slim down the engine whilst co-currently increasing trust. And generate desired pressure ratios with in the Engine.

As it is now. The engine is only effective when used in twin engine format. But since the LCA is single engine to reduce costs this alternative was not acceptable.

It can even be speculated that this proposed alternative was what offshooted into the MCA. But that's a different subject.

Well i hope that answered your question :cheers:
 
Last edited:
The Kaveri engine only this year has become operational. With no flas in design.

The IAF being uncompromising as it is wants further trials and tweaking of the engine. Till then they have the GE-404 which has been tried and tested with over 1000 flights on tejas. Inducting the desperately need first squadron with an Imported engine that was already bought 2 years prior.

But the major issue is that The Kaveri weighs more then it shoudl about 200-400 Kg more.
And LCA also weighs more then it was supposed to.
Combined it was felt the Increased weight would effect Payload size.
For long range missions.

so in order for the project to move forward.
The engine needs to either produce more trust or slim down.
Or preferably a little bit of both.

That's why India wants to bring Schema in to help with the Engine work. They want to Slim down the engine whilst co-currently increasing trust. And generate desired pressure rations with in the Engine.

As it is now. The engine is only effective when used in twin egine format. But since the LCA is single engine to reduce costs this alternative was not acceptable.

It can even be speculated that this proposed alternative was what offshooted into the MCA. But that's a differnet subject.

Well i hope that answered your question :cheers:

Thanks gogbot that is a nice explanation :smitten:and i hope other understant it :angel:
 
Broadsword

here we come PV5 twin seater to fly today ....

by Ajai Shukla
Bangalore
Business Standard, 26th Nov 09


On Thursday morning the first prototype twin-seater, trainer version of the Tejas Light Combat Aircraft (LCA) will taxi out to the runway in Bangalore. With its design team watching tensely from the sidelines, the two test pilots will rev up the engine, race down the runway and, if all goes according to plan, lift the twin-seat Tejas into the sky for its first ever flight.


In the cockpit will be two of the IAF’s most skilled test pilots, now a part of the National Flight Test Centre (NFTC), which handles all Tejas test flying. Air Commodore Rohit Verma, a MiG-21 ace will be the commander; behind him will be Group Captain RR Tyagi, a veteran Jaguar pilot.


Over the last few days the first twin-seat Tejas, called Prototype Version 5 (PV-5) has been carrying “high-speed taxi trials”. In these, the Tejas PV-5 has been speeding down the runway at speeds of over 200 kilometers/hour, applying the brakes just short of take-off speed. But on Thursday the pilot will not brake; keeping the throttle pressed he will pull back the joystick and make history as the trainer actually takes off.


The first flight of the twin-seat Tejas is a crucial landmark in the LCA programme. With the first squadron of the single-engine, single-seat Tejas already ordered by the IAF, and the order for the second squadron being processed, twin-seat trainers are urgently needed for training the IAF pilots who will man these two squadrons. Every IAF squadron is authorised 18 single-seat fighters and 2 twin-seat trainers.


The twin-seat Tejas is also important for the Indian Navy. The naval version of the Tejas, which will operate off aircraft carriers, will be based on the Tejas trainer; it’s higher cockpit allows the pilot a view of the carrier landing deck while descending steeply to land. In the naval Tejas there is no second cockpit; its place is taken by an extra fuel tank and some avionics.


Single-seat Tejas prototypes have completed about 1200 test flights, but the first flight of the twin-seat trainer is almost like testing a new aircraft. Though the trainer’s engine and fuselage is the same as the single-seater’s, internal systems have been extensively re-engineered to create space for a second cockpit, complete with a second set of controls, for the trainee pilot. Flight-testing will determine whether this new configuration works perfectly.


The twin-seat Tejas’ first flight comes almost 6 months later than originally planned, because the agency developing the Tejas --- the Aeronautical Development Agency --- wants to minimise the chances of a failed test. The ADA chief, PS Subramaniam, told Business Standard in Bangalore in August that caution in flight-testing was one of the drawbacks in the Tejas programme, but was understandable given that India was testing and certifying a modern fighter for the first time.


European aerospace consortium, EADS, which has been appointed consultant for the air force Tejas programme, is expected to advise on how to cut down on flight-testing without compromising safety. Reducing flight-testing by a year, believes Subramaniam, would save Rs 1000 crores in costs and bring the Tejas into operational service early.


In the absence of major hiccups, the twin-seat Tejas trainer is expected to complete testing and certification by 2014 and start being delivered to the IAF by 2015.
:taz:
 
The Kaveri engine only this year has become operational. With no flaws in design.

The IAF being ever uncompromising , wants further trials and tweaking of the engine. Till then they have the GE-404 which has been tried and tested with over 1000 flights on tejas. Inducting the desperately need first squadron with an Imported engine that was already bought 2 years prior, was really the quickest step forward.

But the major issue is that The Kaveri weighs more then it should about 200-400 Kg more.
And LCA also weighs more then it was supposed to.
Combined it was felt the Increased weight would effect Payload size.
For long range missions.

so, in order for the project to move forward.
The engine needs to either produce more trust or slim down.
Or preferably a little bit of both.

That's why India wants to bring Schema in to help with the Engine work. They want to Slim down the engine whilst co-currently increasing trust. And generate desired pressure ratios with in the Engine.

As it is now. The engine is only effective when used in twin engine format. But since the LCA is single engine to reduce costs this alternative was not acceptable.

It can even be speculated that this proposed alternative was what offshooted into the MCA. But that's a different subject.

Well i hope that answered your question :cheers:

first of all, thanks for the explanation. :cheers:

Specification (GTX-35VS Kaveri)

General characteristics

* Type: Afterburning turbofan
* Length: 137.4 in (3490 mm)
* Diameter: 35.8 in (910 mm)
* Dry weight: 2,427 lb (1,100 kg) [Production model goal: 2,100 lb (950 kg)]

Specification (F404-GE-402)
General characteristics

* Type: Afterburning turbofan
* Length: 154 in (3,912 mm)
* Diameter: 35 in (889 mm)
* Dry weight: 2,282 lb (1,036 kg)

Compare with F404, Kaveri is a bit overweight but not that much only abt 70kg? To me that's not significant 'bad' enough for not using it as LCA's engine as both LCA and Kaveri are so important for India. Furthermore their thrust-to-weight ratio is same: 7.8:1 (76.0 N/kg)
 
Last edited:
first of all, thanks for the explanation. :cheers:



Compare with F404, Kaveri is a bit overweight but not that much only abt 70kg? To me that's not significant 'bad' enough for not using it as LCA's engine as both LCA and Kaveri are so important for India. Furthermore their thrust-to-weight ratio is same: 7.8:1 (76.0 N/kg)

That is odd, an article i read during the start of the year cited weight problems.

India's LCA unlikely to use Kaveri engine until Middle of the Next Decade
(this was before the Successful high latitude tests and other flight tests that took place during the middle of the year)


Either some weight reduction has taken place or the Specs are wrong so i went to the DRDO website to make sure.

and well enough their specs are accurate.

Kaveri-Special Characteristics
Air-mass flow : 78 kg/s
By-pass ratio : 0.16
Overall pressure ratio : 21.5
Turbine entry temperature : 1487-1700 K
Maximum dry thrust : 52 kN (5302 kg)
Maximum dry SFC : 0.78 kg/hr/kg
After burner maximum power thrust : 81 kN (8260 kg)
After burner maximum power SFC : 2.03 kg/hr/kg
Thrust-to-weight ratio : 7.8
Application : Indian LCA

Frankly the only reason i can cite for the engine not to be used now. is that more tests are necessary.
And the engine it self is still incomplete having not archived at least 99% of its design specifications. Nor has the Current model of the engine ever completed a test flight on the LCA.

Good observation there Merilion, you had me stumped for a bit.

Then again a topic that very few people seem to discuss is the problems, Using the Ge-404. IAF does consider it underpowered for a reason. India has already bought the Ge-404 in bulk before DRDO actually got the Kaveri operational. As i said in my previous post they are using it as it is the quickest route at this point to get the first batch of planes.
It wasn't the ideal engine to begin with and that's why The there is search for a newer and better engine for use int he aircraft, Till the Kaveri is ready.

I still hope That IAF chooses Rafael, SCHEMA then provides assistance in getting the engine to function at peak efficiency. SCHEMA has also said that It will replace the India Rafael engines with the Kaveri engines that are more powerful.

Frankly speaking however if progress is being made with resolving either the trust or weight issues. Then me yet may see the Engine inducted in the MK-2.
 
Sorry for Answering a question from Year ago, and bring back a dead thread.

But i just happen to be reading some of the comments on the handful on thread i made, and luck would have it i just came across some info to actually answer it this time.

ps: @ Gogbot, if LCA and Rafale are on a comparative grounds, given both were meant to improve upon M2K design,

why doesnt the LCA have canards or twin engines? Was that ever considered? Why go for delta wing design considering LCA was/is to be a multi-role platform?

nal_wtmodels.jpg


Wind Tunnel Models from when LCA was still being designed.
The Aircraft on the left looks very familiar.

Constructing the models themselves and the actual wing tunnel testing, are both expensive ventures, meaning that there must have been a level of seriousness behind the design. The other model is that of the HAL HF-73 concept.

Early LCA with Cranked Arrow Design

05292005104218pm.jpg


Keep in Mind The LCA had many prototypes and many a issues with IAF deciding on its requirements. HAL , NAL and ADA all would have been trowing around various concepts to fit those ever changing Requirements .

Stuff like Avionics Editions that were added to the plane , increasing its weight. Those were not part of the original requirements.

(Take note: i am saying "LCA" and not Tejas , LCA is a requirement for a Light Combat Aircraft , Whilst Tejas is what was designed for That LCA)

Why go with a delta wing design ?
Well i am not really an expert , to answer this with Justice.
I have read that answer before , for an expert. So i know its there.

But i can say , Our MMRCA search for Multi-role aircraft .
Has Three Delta wing aircraft Participating and All three of them are top contenders.

You should also keep in mind.
Originally intended to serve as an air superiority aircraft with a secondary "dumb bomb" ground-attack role, the flexibility of this design approach has permitted a variety of guided air-to-surface and anti-shipping weapons to be integrated for more well-rounded multirole and multimission capabilities.

Hope this is still relevant to you in some way Gubbi :cheers:
 
nal_wtmodels.jpg


Wind Tunnel Models from when LCA was still being designed.
The Aircraft on the left looks very familiar.

Looks familiar but is not the Rafale, that's a model of the BAE P106B as far as I could find out. It is one of the early design concepts from BAE for the Eurofighter, but they went with a twin engine fighter and it is believed that this design was proposed to Saab and HAL instead:

attachment.php


attachment.php


Any Drawings of pre-Eurofighter BAe Design Studies? P.96, P.106, P.110 or ACA? - Key Publishing Ltd Aviation Forums
 
you indians impress me deeply with your incredible perseverance over incredible long time, then the incredible result will certainly be seen i guess, as no country including malaysia can keep embracing a non-effective project, so keep it up !

I think you get impress very quickly, please make sure next time impress when someone do really good job, not a joke like this.
 

Pakistan Defence Latest Posts

Pakistan Affairs Latest Posts

Back
Top Bottom