Indian Space Research Organization (ISRO) has successfully ground tested an improved version of the solid propellant strap on motor for PSLV. The new motor, PSOM-XL, was static tested at SDSC SHAR, Sriharikota on December 29, 2005. PSLV at present employs six solid propellant strap-on motors, each carrying 9 tonne of propellant. The new version, PSOM-XL, with a length of 13.5 m, has the capacity to carry 12.4 tonne. The motor developed a peak chamber pressure of 4.16 MPa and burned for a duration of 58 seconds in the ground test conducted today. The performance of the new motor, developed by ISRO’s Vikram Sarabhai Space Centre at Thiruvananthapuram, was as per the prediction. PSOM-XL will enable improve the capability of PSLV from the present 1450 kg to 1600 kg and will be employed in future PSLV flights including for launching Chandrayaan-1 and the microwave remote sensing satellite, RISAT.