In a landmark of commercial success ,ISRO on 16th December 2015, launched six Singaporean satellites. This was the first time when no Indian satellite was not on board. The launch was done with  Polar Satellite Launch Vehicle’s core alone (PSLV-CA) variant.

To further enhance its technical capability,, apart from launching the six foreign satellites, ISRO also tested the rocket’s fourth stage/engine’s ability to restart after it was cut off around 17 minutes into the flight.

Technically speaking, India was testing a multiple burn fuel stage/rocket engine for the first time.

The successful launch of the six Singaporean satellites have taken Isro’s total flights of foreign satellites to 57.

Last month, India also launched its communication satellite GSAT-15 using the Ariane rocket of the European space agency which takes the total number of satellite launches in 2015 to 21 (17 foreign, four Indian).

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