Geosynchronous Satellite Launch Vehicle

GSLV Mk-I
Geosynchronous Satellite Launch Vehicle Geosynchronous Satellite Launch Vehicle
Stages		3
1a - Core Booster	Engines	1 × S125 Solid propelled motor
Thrust		4,700 KN
Burn time		100 seconds
Fuels		HTPB
1b - Strap-ons	Engines	4 × L40H Liquid propelled Vikas engines
Thrust		680 kN × 4 = 2,720 kN
Burn time		160 seconds
Fuels		N2O4/UDMH
2 - Second stage	Engine	1 × GS2 Liquid propelled stage
Thrust		720 kN
Burn time		150 seconds
Fuels		N2O4/UDMH
3 - Third stage	Engine	1 × GS3 Cryogenic stage
Thrust		73.5 kN
Burn time		720 seconds
Fuels		LOX/LH2
Launch Vehicle		1st Launch April 18, 2001
Payload LEO 18-deg		5,000 kg
Payload GTO		2,200 kg

The GSLV or Geosynchronous Satellite Launch Vehicle was developed by Indian Space Research Organization (ISRO) to launch INSAT-type satellites into geostationary orbit to make India less dependent on foreign rockets. The GSLV improved on the performance of the PSLV with the addition of liquid strap-on boosters and a cryogenic upper stage. It is a three-stage launch vehicle with the first stage being solid-propelled, the second liquid-propelled and the final stage being cryogenically propelled. The solid first and liquid second stages are carried over from the PSLV. The GSLV used cryogenic upper stage supplied by Russia, having ordered 7 upper stages. India originally tried to buy the technology to build a cryogenic upper stage from Russia, but under pressure from the United States, that technology was not provided. Therefore, ISRO has been working on developing a cryogenic upper stage for the past eleven years.

The first two flights of the GSLV were developmental. The first, partially successful, flight was on 18 April 2001 which launched GSAT-1. The second, which was fully successful, was on 8 May 2003 launching the experimental communication satellite GSAT-2. The first operational flight (GSLV-F01) was the launch of the EDUSAT communications satellite on 20 September 2004.

The fourth flight (GSLV-F02) on 10 July 2006 was unsuccessful in launching the 2168 kg (4,780 lb) communications satellite INSAT-4C as both rocket and satellite had to be destroyed over the Bay of Bengal after the rocket's trajectory veered outside of permitted limits [1]. A defective propellant regulator of the fourth strap-on motor caused the INSAT-4C-carrying vehicle to crash a minute after lift-off from Sriharikota on the Andhra Pradesh coast on 10th July 2006 [2]. The next launch of GSLV (GSLV-F03) is expected to be conducted during July 2007. This would carry INSAT-4CR, which is the replacement satellite for INSAT-4C.[3]

The four flights of GSLV so far have used Russian cryogenic engine for the last stage. The next flight is expected to use the cryogenic engine developed by ISRO.

The GSLV uses four L40 liquid strap-on boosters and can place approximately 5000 kg (11,000 lbm) into an easterly LEO orbit. Using the Russian 12KRB upper stage, with KVD-1 cryogenic rocket engine, GSLV can place 2200 kg (4,850 lbm) into an 18 degree Geosynchronous Transfer Orbit(GTO) orbit.

Basic specifications

• Overall length: 49 m
• Lift-off weight: 401 t
• Number of stages: 3
• Payload: GSAT
• Launch Orbit: Geosynchronous Transfer Orbit(GTO) 180 x 36,000 km

First stage

S125 stage is 2.8 m in dia. and is made of M250 grade maraging steel and it has a nominal propellant loading of 129 t.

The L40 strap-ons (derived from the L40 second stage) are loaded with 40 tons of hypergolic propellants (UDMH & N2O4) stored in two independent tanks of 2.1 m diameter in tandem and has a pump-fed engine of 680 kN thrust.

Second stage

The second stage is 2.8 m in diameter and is loaded with 37.5 t of liquid propellants (UDMH & N2O4) in two compartments of an aluminium alloy stage tankage separated by a common bulk head. This has a pump-fed engine of 720 kN thrust.

Third stage

The third stage is 2.8 m in diameter and uses liquid hydrogen (LH2) and liquid oxygen (LOX) in two separate tanks of aluminium alloy interconnected by an inter-stage propellant loading is 12.5 t. ISRO is planning to use its own cryogenic engine from the fifth planned GSLV flight, which is being activelly developed and tested in ISRO's Liquid Propulsion Centre(LPSC).

The Indian Cryogenic engine was tested for 50 seconds producing a trust of 7.5 tonnes. The ISRO would go for a full-duration test of the indigenous cryogenic stage for 720 seconds in 2007 which is the actual duration required by GSLV to place a satellite in GTO orbit.

Launch log

Version	Date of Launch	Launch Location	Payload	Mission Status
D1	18 April 2001	Sriharikota*	GSAT-1	Unsuccessful, Developmental Flight
D2	8 May 2003	Sriharikota*	GSAT-2	Success, Developmental Flight
FO1	20 September 2004	Sriharikota*	EDUSAT	Success, First operational flight
FO2	10 July 2006	Sriharikota*	INSAT-4C	Unsuccessful; both rocket and satellite had to be destroyed over the Bay of Bengal after the rocket's trajectory veered outside of permitted limits.

Comparable Rockets

• Proton
• Delta II
• Ariane 3

Trivia

• The GSLV-Mk III is the successor to this rocket, and is scheduled for launch around 2007-2008.
• The GSLV variant with a different cryogenic stage is technically known as the GSLV-II, hence the GSLV-III's name.
• A modified GSLV-Mk II is being considered for India's proposed manned mission in 2014. The GSLV-I/II has the capability to lift a 3-4 tonne Gemini-class capsule carrying two cosmonauts.[4][5]

External links

• ISRO GSLV Page
• India in Space GSLV Page
• 12KRB (KVD-1) upper stage at Khrunichev Space Center