Hormuz Mama/MUMBAI
A flight-ready production standard Kaveri turbofan (number K-5)for India's Light Combat Aircraft (LCA) will be ready by the middle of this year. Project engineers say engine K-4 is being assembled at India's Gas Turbine Research Establishment (GTRE).
GTRE plans to build 17 test engines, with production beginning in 2002. Only K-3 has been shown, at last year's Aero India show in Bangalore.
About 850h of a 2,500h ground test programme has been completed. The core unit of the engine, known as Kabini, has been flight tested in Russia at the Central Aviation Engines Institute. The tests were conducted at altitudes from 3,000ft (900m) to 45,000ft and, says GTRE, demonstrated satisfactory combustor light-up and stability.
A complete engine is due to be test flown in Russia on a Tupolev Tu-16 testbed at the end of this year, clearing the engine up to Mach 0.8.
The engine will be integrated with the LCA airframe around the same time, leading to a first flight of the LCA/Kaveri combination in 2001, with flight trials in 2002. The Indians say the aircraft will enter service in 2003.
The LCA has yet to fly, although the aircraft was rolled out three years ago. The latest problems concern work on the flight controls. The prototype is powered by a General Electric F-404.
Kaveri is a three-stage, low bypass turbofan with a first stage of transonic titanium blades, fixed inlet guide vanes and a 3.3:1 pressure ratio. The compressor is a six-stage unit with variable geometry inlet vanes on the first two stator stages and a 6.5:1 pressure ratio. Both stages are driven by a single-stage power turbine with cooled blades of a directionally solidified material.
The engine has a short annular combustor with dump diffuser and variable nozzle. Although the power turbine blades are produced abroad, India's Defence Materials Research Laboratory is studying a locally built blade.
Kaveri's full-authority digital engine control is also under development by GTRE.
The initial production version will have a dry thrust of 11,700lb (52kN) and reheat thrust of 18,000lb and a thrust/weight ratio of 7.8:1. The engine has an in-built 25%growth factor in its design, which will partly be achieved with the use of single crystal blades and variable inlet guide vanes for the low pressure compressor. A long-term aim is the development of a thrust vectoring nozzle, possibly leading to elimination of the LCA's vertical fin.
Source: Flight International
