PSLV XL success – IRNSS-1F on orbit !

Second launch of Indian Regional Navigation Satellite System (IRNSS) satellite in 2016 became success - ISRO confirmed with this launch that PSLV is reliable rocket and India has potential to offer launch services on very high level.

Indian Regional Navigational Satellite System is developing and this year is good example of consequence of ISRO in implementing own navigation system. Three satellites were scheduled for 2016 and today we are after second launch of IRNSS-1F and sixth, penultimate satellite from IRNSS series. Launch was performed at 10:31 GMT. After twenty minutes at 10:41 GMT satellite was deployed by fourth stage of the rocket and started series of maneuvers to reach correct orbital slot 32.5° East at altitude of 35700 km and inclination at 5°.

Satellite is based on I-1K bus developed by ISRO with operational life at around 12 years. Satellite dimensions are 1.505 m × 1.476 m × 1.530 m with mass at 1425 kg. Satellite's power consumption is 1300 w which are provided by two deployable solar arrays combined with onboard battery. Propulsion of the satellite is Liquid Apogee Motor with 440 N of thrust and 12 thrusters for performing maneuvers (each providing 22 N). Satellite is equipped with following devices: Code Division Multiple Access (CDMA) device with retroreflector array, Rubidium atomic clock, L5 (frequency of 1176.45 MHz) and S band (frequency of 2492.028 MHz) transponders for downlink, C band transponder for determining satellite position, C band transponder for uplink on frequency 6700 – 6725 MHz and downlink on 3400-3425 MHz and additional laser rangefinder.

According to previous assumptions, due the mass of satellite, ISRO decided to utilize PSLV XL rocket in this mission. PSLV XL is still long for 44 m and equipped with six boosters rocket with mixed solid and liquid propulsion, but boosters were stretched comparing to PSLV. They are called PSOM-XL and are equipped in bigger boosters (1m diameter and length at 13.5 m) with 30% more solid fuel (12000 kg). Rocket weighs 320000 kg and is able to lift 1425 kg to GTO orbit. Central core with four stages is identical as core of PSLV. First stage is powered by solid fueled (HTPB) S139 engine with 4800 kN of thrust. Second stage is equipped with one Vikas engine liquid fueled with N2O4/UDMH and providing 799 kN of thrust. Third stage is again equipped with solid fueled propulsion - HPS3 engine generates 240 kN of thrust. Fourth stage is powered by two L-2-5 engines with thrust at 15.2 kN burning liquid MMH/MON propellant.