Sriharikota: A new variant of the India’s Polar Satellite Launch Vehicle (PSLV) rocket on Monday carrying the electronic intelligence satellite, Emisat for the Defence Research Development Organisation (DRDO) and 28 other third party satellites lifted off from the second launch pad here. About 17 minutes into the flight, the rocket would eject the 436 kg Emisat into a 749 km orbit.

“There is increased demand for satellites from strategic sectors. About six/seven satellites are planned to be built,” a senior official told IANS on the condition of anonymity. After putting into orbit the Emisat, the rocket will be brought down to put into orbit the 28 foreign satellites at an altitude of 504 km.

This will be followed by bringing the rocket down further to 485 km when the fourth stage/engine will turn into a payload platform carrying three experimental payloads: (a) Automatic Identification System (AIS) from ISRO for Maritime satellite applications capturing messages transmitted from ships (b) Automatic Packet Repeating System (APRS) from AMSAT (Radio Amateur Satellite Corporation), India – to assist amateur radio operators in tracking and monitoring position data and (c) Advanced Retarding Potential Analyser for Ionospheric Studies (ARIS) from Indian Institute of Space Science and Technology (IIST) – for the structural and compositional studies of ionosphere, the space agency said.

The whole flight sequence will take about 180 minutes from the rocket’s lift off at 9.27 a.m. The 28 international customer satellites — 24 from the US, two from Lithuania and one each from Spain and Switzerland — will weigh about 220 kg. “It is a special mission for us. We will be using a PSLV rocket with four strap-on motors. Further, for the first time we will be trying to orbit the rocket at three different altitudes,” Indian Space Research Organisation Chairman K. Sivan had earlier told IANS.

The PSLV is a four-stage engine expendable rocket with alternating solid and liquid fuel. In its normal configuration, the rocket will have six strap-on motors hugging it’s first stage. But the 44.5 metre tall rocket that lifted off on Monday had four strap-on motors and its configuration is designated as PSLV-QL.