PSLV-C18 puts four satellites in orbit

India's Polar Satellite Launch Vehicle (PSLV-C18) demonstrated its reliability and consistency yet again when it put four satellites in orbit with aplomb on October 12.

The satellites were: Megha-Tropiques, an Indo-French mission to study the weather and climate in the tropical regions of the world; SRMSat, built by students of SRM University, near Chennai; Jugnu, put together by Indian Institute of Technology, Kanpur students; and VesselSat from Luxembourg.

The fourth stage fired the four in orbit after 21 minutes of a flawless flight, the 19th consecutive success of the PSLV, prompting P.S. Veeraraghavan, Director, Vikram Sarabhai Space Centre, Thiruvananthapuram, to brand it a “Perfect Satellite LaunchVehicle.”

K. Radhakrishnan, Chairman, Indian Space Research Organisation (ISRO) called the flight “a grand success” and said the information received from the Megha-Tropiques satellite would be useful to the global community for measuring the precipitation in the tropical regions of the world. Twenty-one scientific teams from several countries would use the information for doing research on weather in the tropical countries.

S. Ramakrishnan, Director, Liquid Propulsion Systems Centre, ISRO, describing it as “a magnificent mission,” said: “Today, with the PSLV, we have an assured access to space. This is something that not many countries can boast of.”

There were patches of clouds above the spaceport as the PSLV-C18 soared from the seaside first launch pad at 11.01 a.m., after a delay of one minute. “We shifted the launch by a minute,” Dr. Radhakrishnan explained, to preclude the “probability of space debris,” smashing into the satellites.

T.K. Alex, Director, ISRO Satellite Centre, Bangalore, said space debris travelled at a velocity of eight km a second and so the ISRO did not want to take any chances.

The vehicle lifting majestically quickly disappeared into a bank of clouds. As it knifed out, it looked spectacular, riding on bright yellow flames and climbing nonchalantly into the sky. Clouds blanketed it again but it emerged, gathering velocity. The engines worked with clock-work precision, erupting into life on the dot and jettisoning into the Bay of Bengal after spending themselves out.

After the third stage burn-out, the fourth stage coasted on its own, without any power, that is, without firing. The vehicle was gaining altitude all the time Then, the two engines in the fourth stage started up, and 21 minutes after lift-off, the four satellites were shot into orbit one after the other, at a velocity of 26,000 km an hour.

Megha-Tropiques went into orbit at an altitude of 865 km against the targeted 867 km.