India’s PSLV Blazes Its Own Path to Space

PSLV C-28 Lifts Off : Image Credit ISRO

As many in the U.S. ponder the immediate future of commercial space launch industry in the aftermath of SpaceX’s surprising failure on the NASA CRS-7 mission to the International Space Station, rising space power India has taken another small but significant step in expanding its own commercial capabilities.

On Friday evening, at 9:58 PM IST, an Indian Polar Satellite Launch Vehicle, or PSLV, lifted off from the First Launch Pad at the Satish Dhawan Space Centre (SDSC) SHAR, Sriharikota. It was the 29th consecutive successful flight of the PSLV, a remarkable record in itself for what has turned to be a workhorse rocket for the Indian Space Research Organization, and Antrix, its commercial arm. It was also the 9th flight of the rocket’s heaviest, or XL version, which lifts off with 6 solid rocket strap-on boosters. What stood out about Friday night’s flight however, is the fact that it was the first XL to perform a fully commercial mission for a non-Indian customer. Secured aboard under the payload fairing via a custom designed adapter, were three commercial Earth Observation spacecraft for DMC International Imaging, a wholly owned division of Great Britain’s Surrey Satellite Technology.

The satellites, DMC3A, DMC3B and DMC3C will join the DMC Consortium, a fleet of separately owned Earth imaging satellites managed by DMC Imaging International  which is employed individually on a commercial basis and collectively on a humanitarian basis to provide free observational images of major disasters. In addition to the DMCII spacecraft, two smaller satellites, CBNT-1 and DeOrbitSail, and experimental cubesat rode the PSLV to a 647 km Polar Sun Synchronous orbit as well.

To put it charitably, the PSLV is a bit of a Frankenrocket, consisting of alternating solid and liquid fueled cores. The solid first stage uses a strontium perchlorate fluid injection for pitch and yaw, while roll control is provided by two small liquid thrusters. The second stage is a hypergolic, burning a toxic combination of UDMH and N2O4. The third stage is solid, whereas the fourth, which provides coast and restart capability is again fliquid. When the six solid strapon boosters are included, two are air-started 25 seconds into the flight. And yet for all this, the PSLV has amassed an admirable track for which SpaceX and its 21st century Falcon 9 have no remaining margin of error for matching. According to a 2014 report on the launch of a French SPOT commercial imaging satellite, the PSLV in its core alone version without the strap-ons, cost 90 Crore, or approximately $15 million USD, making it a vey cost effective booster.

To be clear, the PSLV and the Falcon are not, and never will be competitors, but in the growing debate over launch vehicle reliability which was ignited by the latter’s June 28th failure, there is something interesting in the disparity between the two systems which is altogether different than differences with SpaceX’s most commonly cited competitors. If nothing else, it demonstrates the truth in the adage that there is no one correct way to reach orbit.

It also makes one wonder what India is capable of achieving if it ever sets about the task of developing a greatly simplified and truly modern booster.