It's the biggest day in the history of India as India's Polar Satellite Launch Vehicle, PSLV-C14, in its 16th Mission launched 958 kg Oceansat-2 and six nano-satellites into a 720 km. intended Sun Synchronous Polar Orbit (SSPO) on September 23, 2009, before this PSLV has launched multiple satellites into orbit with the maximum number being 10 during PSLV-C9 mission in April 2008.
PSLV is a four-stage launch vehicle employing both solid and liquid propulsion stages. PSLV is the trusted workhorse launch Vehicle of ISRO. During Sep. 1993 - Apr. 2009 period, PSLV had fifteen launches of which fourteen were consecutively successful. PSLV has repeatedly proved its reliability and versatility by launching 39 spacecrafts (17 Indian and 22 for international customers) into a variety of orbits so far. It may be recalled that during its previous mission, PSLV had successfully launched RISAT-2 and ANUSAT spacecrafts on April 20, 2009.
In its standard configuration, the 44 m tall PSLV has a lift-off mass of 295 tonne. It is a four-stage launch vehicle with the first and the third stages as well as the six strap-ons surrounding the first stage using HTPB based solid propellant. PSLV's first stage is one of the largest solid propellant boosters in the world. Its second and fourth stages use liquid propellants.
This mission is unique for PSLV as this is the first time that new AMC/ATS based avionics is being used for a typical SSPO mission. A Core Alone configuration of the vehicle with PS4 L2.5 stage is being employed to put the satellites in orbit. This is the fifth mission of PSLV in Core alone configuration.
Major changes are:
PS4 to use L2.5 stage
Introduction of a 45° inclined deck to mount Rubin spacecrafts on EB
CUBESATs are separated using a separation system SPL supplied along with S/C by the user.
In its sixteenth flight conducted from Satish Dhawan Space Centre (SDSC) SHAR, Sriharikota today (September 23, 2009), ISRO's Polar Satellite Launch Vehicle, PSLV-C14 successfully launched the 960 kg Indian remote sensing satellite Oceansat-2 and six nano satellites for international customers into a polar Sun Synchronous Orbit (SSO). This was the fifteenth successful flight of PSLV.
After a 51 hour count down, PSLV-C14 lifted off from the first launch pad at SDSC SHAR, at 11:51 am IST with the ignition of the core first stage. The important flight events included the separation of the first stage, ignition of the second stage, separation of the payload fairing at about 125 km altitude after the vehicle had cleared the dense atmosphere, second stage separation, third stage ignition, third stage separation, fourth stage ignition and fourth stage cut-off.
The 960 kg main payload, Oceansat-2, was the first satellite to be injected into orbit at 1081 seconds after lift-off at an altitude of 728 km. About 45 seconds later, four of the six nano satellites were separated in sequence. The initial signals indicate normal health of the satellites.
Oceansat-2 is the sixteenth remote sensing satellite of India. The state-of-the-art Oceansat-2 carries three payloads and has the shape of a cuboids with two solar panels projecting from its sides.
The eight band Ocean Colour Monitor (OCM) payload carried by Oceansat-2 images a swath (strip of land or ocean) of 1420 km width with a resolution of 360 metre and works in the Visible and Near Infrared region of the electromagnetic spectrum. The Ku-band Scatterometer with a 1 metre diameter antenna rotating at 20 rpm, works at a frequency of 13.515 GHz. The Scatterometer covers a swath of 1400 km and operates continuously. ROSA is a GPS Receiver for atmospheric sounding by radio occultation built by Italian Space Agency (ASI).
Soon after separation from PSLV fourth stage, the two solar panels of OCEANSAT-2 were automatically deployed. The satellite's health is continuously monitored from the ISRO Telemetry, Tracking and Command Networks (ISTRAC) Spacecraft Control Centre at Bangalore with the help of a network of ground stations at Bangalore, Lucknow, Mauritius, Biak in Indonesia and Svalbard and Tromso in Norway as well as a station in Troll, Antarctica.
PSLV-C14 mission carried six nano satellites - Cubesat 1, 2, 3 and 4 as well as Rubin 9.1 and 9.2 - as auxiliary payloads along with Oceansat - 2. The weight of these nano satellites was in 2-8 kg range. Oceansat - 2 and the six auxiliary payloads were placed in a polar Sun Synchronous Orbit inclined at an angle of 98.28 degree to the equator.
The auxiliary payloads of PSLV-C14 are educational satellites from European Universities and are intended to test new technologies. After the separation of Oceansat - 2 from PSLV - C14, the four cubesats were also separated, while Rubin 9.1 and 9.2 remain permanently remain attached to the upper stage of PSLV-C14.
The 44.4 metre (147 ft) tall PSLV - C14 weighed 230 tons at lift-off. PSLV - C14 is the core alone version of PSLV which is the same as PSLV standard configuration except for the strap-on motors. Six such strap-ons surround the first stage of PSLV standard configuration, but are absent in core alone version. PSLV-C14 was the fifth core alone mission of PSLV.
PSLV - C14 had four stages using solid and liquid propulsion systems alternately. The first stage, carrying 139 tonne of propellant, is one of the largest solid propellent boosters in the world. The second stage carried 41.5 tonne of liquid propellant. The third stage used 7.6 tonne of solid propellant and the fourth had a twin engine configuration with 2.5 tonne of liquid propellent.
This was the sixteenth mission of ISROs workhorse launch vehicle PSLV and its fifteenth consecutive success. From October 1994 onwards, PSLV has repeatedly proved its reliability, robust design and versatility by launching satellites into polar Sun Synchronous, Geosynchronous Transfer, Low Earth and Highly Elliptical Orbits. Of the 39 satellites launched by PSLV so far, 17 have been Indian and the rest being satellites from abroad. During many of its missions, including todays PSLV-C14, PSLV has launched multiple satellites into orbit with the maximum number being 10 during PSLV-C9 mission in April 2008.