PSLV-C8

PSLV-C8 is the eleventh flight of ISRO's Polar Satellite Launch Vehicle (PSLV) and its first commercial launch as well. In this flight, PSLV launches the 352 kg Italian astronomical satellite, AGILE, into a 550 km circular orbit, inclined at an angle of 2.5 deg to the equator. An Advanced Avionics Module (AAM), weighing 185 kg, to test advanced launch vehicle avionics systems like mission computers, navigation and telemetry systems, is also flown on PSLV-C8.

A Dual Launch Adapter (DLA) is employed in PSLV-C8 and AGILE is mounted on top of DLA while AAM is mounted inside DLA. With a much lighter payload and the low inclination of the orbit in which AGILE is to be placed, PSLV-C8 is configured without the six solid propellant strap-on motors of the first stage. Also, the propellant in the fourth stage is reduced by about 400 kg compared to previous PSLV flight. The core-alone
PSLV-C8 will have a lift-off mass of 230 tonne.

PSLV has emerged as the workhorse launch vehicle of ISRO with nine consecutively successful flights so far. Since its first successful launch in 1994, PSLV has launched eight Indian remote sensing satellites, an amateur radio satellite, HAMSAT, a recoverable space capsule SRE-1 and six small satellites for foreign customers into 550-800 km high polar Sun Synchronous Orbits (SSO). Besides, it has launched India's exclusive meteorological satellite, Kalpana-1, into Geosynchronous Transfer Orbit (GTO). PSLV will also be used to launch India's first spacecraft mission to moon, Chandrayaan-1, during 2008.

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. PSLV's bulbous payload fairing has a diameter of 3.2 metre. The vehicle has S-band telemetry and C-band transponder systems for monitoring its health and flight status respectively. It also has sophisticated auxiliary systems like stage and payload fairing separation systems.

PSLV was originally designed to place 1,000 kg class of India's remote sensing satellites into a 900 km polar SSO. The payload capability of PSLV has been successively enhanced and in its ninth flight, PSLV-C6, in May 2005, it launched two payloads – 1,560 kg CARTOSAT-1 and 42 kg HAMSAT – into a 620 km SSO. In its previous flight, PSLV-C7, it launched four payloads – 680 kg CARTOSAT-2, 550 kg Space capsule Recovery Experiment (SRE-1), 56 kg LAPAN-TUBSAT of Indonesia and the 6 kg PEHUENSAT-1 of Argentina – into a 635 km high polar SSO with an inclination of 97.9 deg with respect to the equator.

PSLV-C8 is launched from the Second Launch Pad at Satish Dhawan Space Centre SHAR, Sriharikota, the spaceport of India, situated at a distance of about 80 km North of Chennai in the Nellore district of Andhra Pradesh state. Compared to many space launch centers of the world, Sriharikota's proximity to Equator is especially advantageous for launching payloads Eastwards. It has facilities for solid propellant processing, static testing of solidmotors, launch vehicle integration and launch operations, range operations comprising telemetry, tracking and command network and mission control centre. The second Launch Pad became operational in May 2005.