Tejas LCA Enters Key Test Phase

(Aviation Week) The Tejas Light Combat Aircraft has certainly tested the patience of the Indian air force and the Indian defense establishment, but the coming weeks may finally yield important breakthroughs to fielding the indigenously developed aircraft. Next month, Tejas is due to undergo a second phase of night trials and, if the systems perform as advertised, it will be cleared for night attack, a crucial requirement to achieve full operational clearance (FOC) as a day/night, all-weather platform by December 2012. The Tejas recently began its first phase of night attack trials. The fifth limited-series-production aircraft (LSP‑5), in the final Mk.1 configuration that includes a night-vision-capable cockpit, was used in six night flights in which test pilots conducted mock targeting and attack drills to test simulated avionics and integration of weapons and sensors. The aircraft’s modified ELTA Systems multimode radar and Rafael Litening pod were both tested during the flights. Following the first six tests last month, India’s Defense Research and Development Organization (DRDO) said, “The preliminary results indicate that the integrated system performed very well, meeting the requirements of night operations. The flights also tested the helmet-mounted display system [Elta DASH] and instrument landing system.” With the Indian air force set on establishing its first Tejas squadron in 2013, the next 16 months are crucial for the project test team. There are several flight-envelope expansion tasks still unfinished, including assessing angle of attack, g-forces and sustained turn rate. The next limited-series-production aircraft, LSP-6, is expected to be dedicated to resolving those issues quickly. The air force is putting pressure on developments. Before Tejas reached initial operational clearance (IOC), the service waived some requirements, but it is firm it will not do so again for FOC, Air Chief Marshal Pradeep Naik made clear during a Tejas ceremony in January when IOC was attained. “We’ve waited a long time for the Tejas. We don’t want a partial platform. We want everything fully operational,” he said. The absence of certain capabilities that the Tejas team promised but could not deliver for IOC in January 2011 did not please the service, which was finally forced to extract assurances that the untested capabilities will be completed by next month. These include wake penetration tests as well as all-weather, day/night and lightning clearances. Several test points in weapons delivery in different configurations remain on the team’s must-do list and will continue through into next year. So far, the Tejas has only conducted live drops of gravity bombs and Vympel R-73 (AA-11 Archer) short-range air-to-air missiles. Strike profiles are being tested at the DRDO’s new bombing range outside Bengaluru. In the next few months, Tejas platforms will fire air-to-ground munitions such as cluster weapons, laser-guided bombs and S-8 rocket pods against still and moving targets. Rafael’s Derby beyond-visual-range missile is expected to be a standard on the Tejas, with trials scheduled a year from now. Reports suggest a contract could be signed shortly. In its final Mk.1 configuration, the air force also expects the Tejas to be fully capable of deploying Kh-59-series stand-off strike weapons and Kh-35/31 antiship missiles. The next big item on the program time line is the first flight of the LCA navy variant, expected in the next two months. Its progress has been delayed by issues with weight, landing gear and sink-rate parameters. Meanwhile, India’s troubled and hugely delayed Kaveri turbofan engine development effort—once linked to the Tejas program—has made some progress in flight trials. Between November 2010 and April this year, the engine has powered an Iluyshin Il-76 flying testbed on 11 flights outside Moscow. The Kaveri, delinked from the Tejas program several years ago because of persistent failures to meet requirements, is being completed in cooperation with Snecma (and its M88 ECO core) for India’s fifth-generation Advanced Medium Combat Aircraft and, in a modified form, the country’s concept stealth unmanned combat aircraft known as AURA. Photo: Aviation Week