[Satellite News 07-09-10] The Indian Space Research Organisation (ISRO) shut down half of the transponders on the Insat-4B communications satellite after it suffered a solar panel power glitch July 7 — the latest addition to a list of delays, failures and anomalies that ISRO has endured in 2010.
    After starting of the year strong, ISRO has suffered a series of mishaps. In January, the agency conducted a static test of the S-200 — India’s largest solid rocket booster and part of ISRO’s GSLV-Mk 3 geosynchronous satellite launch vehicle. The S-200 is the third largest solid booster in the world, next to the reusable solid rocket motor, solid booster of NASA’s Space Shuttle and the P-230 solid booster of Arianespace’s Ariane-5 rocket. ISRO expected the launcher to be used for placing heavy satellites in the 4-ton class in geostationary orbit, with the potential to put a 10-ton satellite in a near-earth orbit at an altitude of about 300 kilometers.
    However, ISRO experienced third-stage related issues in April when its GSLV-D3 rocket, carrying the GSAT-4 communications satellite, failed, resulting in loss of control of the spacecraft. The engine failure happened just minutes after liftoff, which caused the rocket to tumble uncontrollably back to Earth. ISRO’s GSLV-D3 mission aimed to debut an Indian-made cryogenic engine in efforts to expand India’s satellite launch business to about $120 million a year and end the country’s dependence on Russian-built cryogenic engines for lifting heavy payloads. The GSAT-4 satellite carried a multi-beam Ka-band bent pipe and regenerative transponder and navigation payload in multiple bands to guide civil and military aircraft.
    ISRO, looking to shake off past issues, including the loss of the $82 million Chandrayaan-1 lunar-orbiting satellite in August, continued to have problems. In May, ISRO postponed the launch of its Polar Satellite Launch Vehicle PSLV C-15 due to technical issues with the launcher. The agency detected a marginal drop in the pressure in the second stage of the vehicle during mandatory checks. The launch was rescheduled for July 12. The PSLV-C15 launch has several potential customers, as the rocket will carry as many as five satellites into space, including Indian mapping satellite Cartosat-2B, Alsat from Algeria, a nanosatellite from Canada, a Swiss nanosatellite and the Studsat satellite. 
    “Detailed analysis of the data will be carried out to find out the reason for non-ignition of two engines,” ISRO Director G. Radhakrishnan said after the incident. ISRO in June appointed Ramakrishnan as director of its liquid propulsion systems center, shaking up the agencies technical leadership in an effort to change course. Ramakrishnan previously served as projects director for ISRO at the Vikram Sarabhai Space Centre, providing technical guidance and program direction to ISRO launch vehicle projects as well as new developmental activities.
    While ISRO’s PSLV-C14 vehicle saw success with the September launch of Oceansat-2 and six nanosatellites, including Jugnu, India’s lightest nanosatellite, ISRO’s latest troubles with Insat-4B may impact broadcast customers, including broadcasters Doordarshan and Sun Direct TV, which use the satellite to support DTH services. Insat-4B, launched by Arianespace in 2007, carries 12 Ku-band and 12 C-Band transponders. ISRO said it had to switch off six of each type of transponder following the anomaly.
    “An expert team is studying the possibilities of partial utilization of some of the transponders that were switched off and restoring the services at the earliest [possible time],” ISRO said in a statement.