CHENNAI: The 50th high performance motor case for the third stage of PSLV that is capable of handling more pressure and carry more weight will be used in the next PSLV mission in the month of May; said K Sivan, director, Vikram Sarabhai Space Centre (VSSC) on Saturday.Sivan said the third stage is one of the very efficient and cost effective stages. The rocket uses a solid motor in its third stage and the 50th high performance motor case for the stage was recently rolled out of VSSC. Sivan was talking at the 25th convocation of Dr MGR Educational and Research Institute where he was conferred an honorary degree. "The third stage uses a solid motor. This stage has a combination of high performance, mass reduction and cost reduction. We will use it in our next PSLV mission," he said.ISRO had earlier said the PS3 motor case was initially made with aramid (synthetic fibres) and epoxy through a filament winding process. But the design and processing parameters followed in making the PS3 motor case was modified after they made certain observations during burst tests of the cases. The processing parameters of the PS3 motor case were optimised to augument the payload capacity of PSLV to meet the future requirement of Isro.PSLV is Isro's most reliable launch vehicle, having placed 226 satellites in orbit as of February 2017. This includes missions like Chandrarayaan-1, Mars Orbiter Mission and NavIC.