Development of the LCA's Kaveri turbofan engine is progressing well at Gas Turbine Research Establishment (GTRE). Five engines are being ground tested; while the first test engine, the Kabini, consisted of only the core module, test runs of the first complete prototype Kaveri began in 1996. The third engine was the first with variable inlet guide- vanes on the first three compressor stages. The fifth unit is already close to the production engine weight, Dr. Harinarayana says. About 17 test engines are to be built, and initial flight tests of the Kaveri are planned for the end of 1999. The first flight in an LCA may follow a year later.

For initial flight tests, Dr. Harinarayana says, an agreement has been signed with Russia for loan of a Tu-16 twinjet, on which the test Kaveri will be mounted in a ventral pod. Engine tests are also planned at a high-altitude test facility, as an important feature of the Kaveri for operation in hot-and-high conditions is flat rating of the engine to maintain thrust to higher temperatures and altitudes. The production Kaveri, with a reheat thrust of 20,200 lbs. (80kN), will be more powerful than the 17,000 lbs. Snecma M88-2 now powering the twin-engined Rafale. It matches the output of the uprated M88-3. GTRE says a growth version of the Kaveri will have a turbine entry temperature of 1 ,8500 C and single-crystal turbine blades being developed by GTRE with the Defence Metallurgical Research Laboratory. Directionally solidified blades are now used.

The new variant, which India says will be at the technology level of the M88, will have a fan pressure ratio of 4:1 and an overall pressure ratio of 27:1. A new combustor will be shorter and lighter than the present unit. The increased, unspecified, dry thrust should allow the aircraft to super cruise (cruise supersonically without the use of reheat). Also under development is a thrust-vectoring nozzle, to enhance its agility, as well as a digital engine control system. The axisymmetric TV nozzle is planned to be flight tested on a later prototype. The nozzle could possibly permit the elimination of the vertical stabiliser and decrease the radar cross section. Plans are already under way for derivatives of the Kaveri; a non-afterburning version for an advanced jet trainer, a high bypass-ratio turbo fan based on the Kaveri core, as well as variants for other applications.

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

Prototypes Versions