GSLV-F01 / EDUSAT(GSAT-3)
/ Activities /
Sep 20, 2004
Back to ISRO
GSLV-F01 is the third flight of ISRO’s Geosynchronous Satellite Launch
Vehicle and this is the first operational flight. In its two
developmental test flights conducted in April 2001 and May 2003
respectively, GSLV successfully launched GSAT-1 and GSAT-2 satellites
into Geosynchronous Transfer Orbits (GTOs).
In the first developmental test flight (GSLV-D1), the vehicle placed
1530 kg GSAT-1 into GTO (Geosynchronous Transfer Orbit) and in the second
developmental test flight
(GSLV-D2), it placed 1825 kg GSAT-2 into GTO. In its first operational
flight (GSLV-F01), GSLV will launch the 1950 kg EDUSAT.
The 49 metre tall GSLV is a three stage vehicle. The first stage, GS1,
comprises a core motor with 138 tonne of solid propellant and four
strap-on motors each with 40 tonne of hypergolic liquid propellants
(UH25 and N204). The second stage has 39 tonne of the same hypergolic
liquid propellants. The third stage (GS3) is a cryogenic stage with 12.5
tonne of Liquid Oxygen and Liquid Hydrogen.
The Aluminium alloy GSLV payload fairing is 3.4 m in diameter and is 7.8
m long. GSLV employs various separation systems such as Flexible Linear
Shaped Charge (FLSC) for the first stage, pyro actuated collet release
mechanism for second stage and Merman band bolt cutter separation
mechanism for the third stage. Spacecraft separation is by spring
thrusters mounted at the separation interface. The three-axis attitude
stabilisation of GSLV is achieved by autonomous control systems provided
in each stage. Single plane Engine Gimbal Control (EGC) of the four
strap-ons of the first stage are used for pitch, yaw and roll control.
The second stage has Engine Gimbal Control (EGC) for pitch and yaw and
hot gas Reaction Control System (RCS) for roll control. Two swivellable
vernier engines using LH2 and LOX provide pitch, yaw and roll control
for the third stage during thrust phase and cold gas system during coast
phase. The Inertial Guidance System (IGS) in the Equipment Bay (EB)
housed above the third stage guides the vehicle till spacecraft
injection. The closed loop guidance scheme resident in the on-board
computer ensures the required accuracy in the injection conditions.
Satish Dhawan Space Centre (SDSC) SHAR, the launch station for GSLV, is
located at 80 km north of Chennai on the east coast of India.