Polar Satellite Launch Vehicle

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Polar Satellite Launch Vehicle

PSLV at Sriharikota
Fact sheet
Function	LEO launch vehicle
Manufacturer	ISRO
Country of origin	India
Size
Height	44 m
Diameter	2.8 m
Mass	294,000 kg
Stages	4
	Capacity
Payload to LEO	3,250 kg
Launch History
Status	Active
Launch Sites	Sriharikota
Total launches	10
Successes	9
Failures	1
Maiden flight	20 September 1993
Boosters (Stage 0)
No boosters	6
Engines	1 solid
Thrust	502.600 kN
Specific Impulse	262 sec
Burn time	44 seconds
Fuel	HTPB (solid)
First Stage
Engines	1 solid
Thrust	4,860 kN
Specific Impulse	269sec
Burn time	105 seconds
Fuel	HTPB (solid)
Second Stage
Engines	1 Viking 4
Thrust	725 kN
Specific Impulse	293 sec
Burn time	158 seconds
Fuel	N2O4/UDMH
Third Stage
Engines	1 solid
Thrust	328 kN
Specific Impulse	294 sec
Burn time	83 seconds
Fuel	Solid
Fourth Stage
Engines	2 liquid
Thrust	14 kN
Specific Impulse	308 sec
Burn time	425 seconds
Fuel	MMH/UDMH

The PSLV or Polar Satellite Launch Vehicle is an expendable launch system operated by the Indian Space Research Organisation (ISRO). It was developed to allow India to launch its Indian Remote Sensing (IRS) satellites into sun synchronous orbits, a service that was, until the advent of the PSLV, commercially viable only from Russia. PSLV can also launch small size satellites into geostationary transfer orbit (GTO).

[edit] Layout

PSLV rocket (left) standing at 44m hight. Also shown are Japan's proposed H-IIB and China's Long March 3B rockets.

The PSLV has four stages using solid and liquid propulsion systems alternately. The first stage is one of the largest solid propellant boosters in the world and carries 138 metric tonnes of Hydroxyl-terminated polybutadiene (HTPB) binded propellant with a diameter of 2.8 m. The motor case is made of maraging steel. The booster develops a maximum thrust of about 4,430 kN. Six strap-on motors, four of which are ignited on the ground, augment the first stage thrust. Each of these solid propellant strap-on motors carries nine metric tonne of HTPB propellant and produces 677 kN thrust. Pitch and yaw control of the PSLV during the thrust phase of the solid motor is achieved by injection of an aqueous solution of strontium perchlorate in the nozzle to constitute Secondary Injection Thrust Vector Control System (SITVC). The injection is stored in two cylindrical aluminum tanks strapped to the solid rocket motor and pressurized with nitrogen. SITVC in two strap-on motors is for roll control augmentation.

The second stage employs the Vikas engine and carries 41.5 metric tonne (40 metric tonne till C-5 mission) of liquid propellant — Unsymmetrical Di-Methyl Hydrazine (UDMH) as fuel and Nitrogen tetroxide (N2O4) as oxidizer. It generates a maximum thrust of 800 kN (724 till C-5 mission). Pitch & yaw control is obtained by hydraulically gimbaled engine (±4°) and two hot gas reaction control for roll.

The third stage uses 7 metric tonne of HTPB-based solid propellant and produces a maximum thrust of 324 kN. It has as Kevlar-polyamide fiber case and a submerged nozzle equipped with a flex-bearing-seal gimbaled nozzle (±2°) thrust-vector engine for pitch & yaw control. For roll control it uses the RCS (Reaction Control System) of fourth stage.

The fourth and the terminal stage of PSLV has a twin engine configuration using liquid propellant. With a propellant loading of 2 metric tonne (Mono-Methyl Hydrazine as fuel + Mixed Oxides of Nitrogen as oxidiser), each of these engines generates a maximum thrust of 7.4 kN. Engine is gimbaled (±3°) for pitch, yaw & roll control and for control during the coast phase uses on-off RCS. PSLV-C4 used a new lightweight carbon composite payload adapter to enables greater GTO payload capability.

[edit] Launches

After some delays, the first launch of the PSLV occurred on 20 September 1993. Although all main engines performed as expected, an altitude control problem was reported in the second and third stages. After this initial setback, ISRO met complete success with the third developmental launch in 1996. Further successful launches followed in 1997, 1999, and 2001.

In September 2002, the 1060 kg KALPANA-1 was launched by PSLV-C4 into GTO. On 17 October 2003, the 1360 kg Earth observing ResourceSat1 was launched by PSLV-C5.

On May 5, 2005, PSLV-C6 launched two satellites into orbit; CARTOSAT-I a stereoscopic Earth observation satellite with cartographic applications, weighing 1560 kg, and HAMSAT providing satellite based radio service for amateur radio operators, weighing 42.5 kg into a high polar orbit (632 x 621 km).

PSLV will continue be the work horse of the ISRO for its launches, especially for LEO satellites and the Chandrayaan Projects. It has undergone several improvements with each subsequent version, especially those involving thrust, efficiency and weight.

On January 10, 2007, the PSLV-C7 carried four satellites - the 680 kg Indian remote sensing satellite CARTOSAT-2, the 550 kg Space Capsule Recovery Equipment (SRE-1), Indonesia's LAPAN-TUBSAT (60kg) and Argentina's 6kg nanosatellite called NANO PEHUENSAT-1 into orbit.^[1]

[edit] Launch log

Next scheduled launch: April, 2007.

[edit] Trivia

• The PSLV-C7 used a device called Dual Launch Adopter for the first time to launch four satellites. ^[2]
• The PSLV-C7 used for the first time a video imaging system on board to take pictures of the separation of the first three satellites from the fourth stage of rocket. ^[3]

[edit] References

• * means Second Launch Pad.

[edit] Notes

[edit] External links

• PSLV launch Video
• ISRO PSLV page
• Bharat-Rakshak PSLV page
• India in Space PSLV page