Indian Regional Navigation Satellite System (IRNSS)-1D launches from Sriharikota pic.twitter.com/vt32ZALUTX — ANI (@ANI_news) March 28, 2015

CHENNAI: India took another step towards putting in place an alternative to the American GPS on Saturday, putting in orbit IRNSS-1D , the fourth of the seven satellites that would form a navigation satellite network.Polar Satellite Launch Vehicle (PSLV-C27) lifted off from Satish Dhawan Space Centre, Sriharikota at 5.19pm and placed IRNSS (Indian Regional Navigation Satellite System)-1D weighing 1,425kg in a sub-geostationary orbit after a 20minutes flight.With the launch of IRNSS 1 D, four active satellites will be transmitting navigation signals. This meets the minimum number of satellites required for the system to be fully functional enabling a navigation receiver to compute position.PSLV-C27 that lifted off from the second launch pad was an `XL' version of the PSLV rocket as was the case with the previous three launches. After injection into the preliminary orbit, the two solar panels of IRNSS 1D were deployed in quick succession.It was a textbook launch as all the four stages performed as planned. The first stage of the rocket successfully separated 130 seconds after the lift-off and the second stage ignited as planned. At 262 seconds, the second stage of the rocket was burned out as planned and soon the third stage was ignited.The Master Control Facility at Hassan will take control of the satellite and perform the initial orbit raising manoeuvres consisting of one manoeuvre at perigree (nearest point to earth) and three at apogee (farthest point to earth). These movements are done using the liquid apogee motor of the satellite till it is placed in a circular geostationary orbit.Speaking after the launch, ISRO director A S Kiran Kumar said, “This was 28th consecutive launch that shows that we have come of age. The satellite is in orbit.”PSLV mission director P Kunhikrishnan said, “The orbit achieved is excellent. We achieved 20, 644km apogee against the targeted 20,650km and reached a perigree of 282.5km against the 284km planned. This process was well within the specification and better than planned.”He also said that the PSLV did four launches this financial year and it had evolved into a world class brand of excellence.Liquid Propulsion Systems Centre director K Sivan said that the precision showed not only maturity of PSLV but also the sleepless work by team members. “The task in front is huge,” he added.VSSC director M Chandraduthan said that 2015 was going to be a critical year as five launches including three PSLV and one GSLV D6 are planned. “There will also be a demonstration of a reusable technology for launch vehicle. One third of ISRO is youngsters which show that the future is bright,” he added.IRNSS 1D carries two payloads- a navigation payload and a ranging payload. The navigation payload will transmit navigation service signals to users, while the ranging payload the satellite has a C-band transponder which helps accurate determination of the range of the satellite. ISRO chairman A S Kiran Kumar has said that the new satellite would help a person on the ground locate his geographical position in the subcontinent.The first three satellites in the series were launched from Sriharikota in July 2013, April 2014 and October 2014.