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
but shamelessly use them to show their superbia 
Naaaa never do that 
and i hope other understant it 
