SNS COLLEGE OF TECHNOLOGY (An Autonomous Institution) DEPARTMENT OF AERONAUTICAL ENGINEERING Subject Code & Name: 16AE407 ROCKETS AND MISSILES Date:

DAY: 01 UNIT:4: STAGING OF ROCKETS AND MISSILES TOPIC: 9: Case study on GSLV Geosynchronous Satellite Launch Vehicle

Geosynchronous Satellite Launch Vehicle abbreviated as GSLV, is an expendable launch system operated by the Indian Space Research Organisation (ISRO). The Geosynchronous Satellite Launch Vehicle (GSLV) project was initiated in 1990 with the objective of acquiring an Indian launch capability for geosynchronous satellites.

The first development flight of the GSLV (Mk.I configuration) was launched on 18 April 2001 was a failure as the payload failed to reach the intended orbit parameters. The launcher was declared operational after the second development flight successfully launched the GSAT-2 satellite. During the initial years from the initial launch to 2014 the launcher had a checked history with only 2 successful launches out of 7.

Geosynchronous Satellite Launch Vehicle Mark II (GSLV Mk II) is the largest launch vehicle developed by India, which is currently in operation. This fourth generation launch vehicle is a three stage vehicle with four liquid strap-ons. The indigenously developed cryogenic Upper Stage (CUS), which is flight proven, forms the third stage of GSLV Mk II. From January 2014, the vehicle has achieved four consecutive successes.

DESIGN

Vehicle Specifications

Height: 49.13 m

Number of Stages : 3

Lift Off Mass : 414.75 tonnes

First Flight : April 18, 2001

TECHNICAL SPECIFICATIONS

i. Payload to GTO (geostationary transfer orbit) : 2,500 kg

GSLV's primary payloads are INSAT class of communication satellites that operate from Geostationary orbits and hence are placed in Geosynchronous Transfer Orbits by GSLV.

K.NEHRU, M.Tech.,(Ph.D) Assistant Professor 16AE409 ROCKETS AND MISSILES

ii. Payload to LEO: 5,000 kg

Further, GSLV's capability of placing up to 5 tonnes in Low Earth Orbits broadens the scope of payloads from heavy satellites to multiple smaller satellites.

Third Stage: CUS

Developed under the Cryogenic Upper Stage Project (CUSP), the CE-7.5 is India's first cryogenic engine, developed by the Liquid Propulsion Systems Centre. CE-7.5 has a staged combustion operating cycle.

Fuel : LOX + LH2 Max. Thrust : 75 kN Burn-time : 720 sec Second Stage: GS2

One Vikas engine is used in the second stage of GSLV. The stage was derived from the PS2 of PSLV where the Vikas engine has proved its reliability.

Engine : Vikas Fuel : UDMH + N2O4 Max. Thrust : 800 kN Burntime : 150 sec First Stage: GS1 The first stage of GSLV was also derived from the PSLV's PS1. The 138 tonne solid rocket motor is augmented by 4 liquid strap-ons.

Engine : S139 Fuel : HTPB Max. Thrust : 4700 kN Burntime : 100 sec

Strap-on Motors

The four liquid engine strap-ons used in GSLV are heavier derivatives of PSLV's PS2, and use one Vikas engine each.

Fuel : UDMH + N2O4 Max. Thrust : 680 kN Burntime : 160 sec

K.NEHRU, M.Tech.,(Ph.D) Assistant Professor 16AE409 ROCKETS AND MISSILES

The 49 metres (161 ft) tall GSLV, with a lift-off mass of 415 metric tons (915,000 lb), is a three-stage vehicle with solid, liquid and cryogenic stages respectively. The payload fairing, which is 7.8 metres (26 ft) long and 3.4 metres (11 ft) in diameter, protects the vehicle electronics and the spacecraft during its ascent through the atmosphere. It is discarded when the vehicle reaches an altitude of about 115 km. GSLV employs S-band telemetry and C-band transponders for enabling vehicle performance monitoring, tracking, range safety / flight safety and preliminary orbit determination. The Redundant Strap Down Inertial Navigation System/Inertial Guidance System of GSLV housed in its equipment bay guides the vehicle from lift-off to spacecraft injection. The digital auto-pilot and closed loop

K.NEHRU, M.Tech.,(Ph.D) Assistant Professor 16AE409 ROCKETS AND MISSILES guidance scheme ensure the required altitude maneuver and guide injection of the spacecraft to the specified orbit. The GSLV can place approximately 5,000 kg (11,000 lb) into an easterly Low Earth orbit or 2,500 kg (5,500 lb)(for the Mk. II version) into an 18° geostationary transfer orbit. Liquid boosters The first GSLV flight, GSLV-D1 used the L40 engine. Subsequent flights of the GSLV used high pressure engines in the strap-on boosters called the L40H. The GSLV uses four L40H liquid strap-on boosters derived from the L37.5 second stage, which are loaded with 42.6 tons of hypergolic propellants (UDMH & N2O4). The propellants are stored in tandem in two independent tanks 2.1 metres (6 ft 11 in) diameter. The engine is pump-fed and generates 760 kilonewtons

(170,000 lbf) of thrust, with a burn time of 150 seconds. First stage GSLV-D1 used the S125 stage which contained 125 metric tons (276,000 lb) of solid propellant and had a burn time of 100 seconds. All subsequent launches have used enhanced propellant loaded S139 stage. The S139 stage is 2.8 m in diameter and has a nominal burn time of 109 seconds. The stage generates a maximum thrust of 4700 kN. Second stage The GS2 stage is powered by the Vikas engine. It has 2.8 metres (9 ft 2 in) diameter. Third stage The third stage of the GSLV Mk.II is propelled by either the Russian KVD-1 or the Indian CE-7.5 cryogenic rocket engine. It uses liquid hydrogen (LH2) and liquid oxygen (LOX).The Indian cryogenic engine was built at the Liquid Propulsion Systems Centre. The engine has a default thrust of 75 kilonewtons (17,000 lbf) but is capable of a maximum thrust of 93.1 kilonewtons (20,900 lbf).

Variants GSLV rockets using the Russian Cryogenic Stage (CS) are designated as the GSLV Mk I while versions using the indigenous Cryogenic Upper Stage (CUS) are designated the GSLV Mk II.[17] All GSLV launches have been conducted from the Satish Dhawan Space Centre in Sriharikota. GSLV Mk. I The first developmental flight of GSLV Mk. I had a 129 tonne (S125) first stage and was capable of launching around 1500 kg into geostationary transfer orbit. The second developmental flight replaced the S125 stage with S139. It used the same solid motor with 138 tonne propellant loading. The chamber pressure in all liquid

K.NEHRU, M.Tech.,(Ph.D) Assistant Professor 16AE409 ROCKETS AND MISSILES engines were enhanced, enabling a higher propellant mass and burn time. These improvements allowed GSLV to carry an additional 300 kg of payload.[The fourth operational flight of GSLV Mk. I, GSLV-F06, has a 15 tonne propellant loading in the third stage, called the C-15. GSLV Mk II This variant uses an Indian cryogenic engine, the CE-7.5, and is capable of launching 2500 kg into geostationary transfer orbit. Previous GSLV vehicles (GSLV Mk.I) have used Russian cryogenic engines.

K.NEHRU, M.Tech.,(Ph.D) Assistant Professor 16AE409 ROCKETS AND MISSILES