International Launch Services (ILS) have launched their Proton-M rocket on Thursday, on a mission which is marking their first ILS launch since the Russian workhorse returned to flight. Launch was on schedule at 18:32 GMT from the Baikonur Cosmodrome in Kazakhstan, with the Proton tasked with deploying the QuetzSat-1 telecommunications satellite for SES, after what was nine hours of flight.
The Proton booster is 4.1 m (13.5 ft) in diameter along its second and third stages, with a first stage diameter of 7.4 m (24.3 ft). Overall height of the three stages of the Proton booster is 42.3 m (138.8 ft).
The first stage consists of a central tank containing the oxidizer surrounded by six outboard fuel tanks. Each fuel tank also carries one of the six RD-276 engines that provide first stage power. Total first stage vacuum-rated level thrust is 11.0 MN (2,500,000 lbf).
Powered by one RD-0213 engine, the third stage develops thrust of 583 kN (131,000 lbf), and a four-nozzle vernier engine that produces thrust of 31 kN (7,000 lbf). Guidance, navigation, and control of the Proton M during operation of the first three stages is carried out by a triple redundant closed-loop digital avionics system mounted in the Proton’s third stage.
The Breeze-M upper stage is the Phase III variant, a recent upgrade which utilizes two new high-pressure tanks (80 liters) to replace six smaller tanks, along with the relocation of command instruments towards the centre – in order to mitigate shock loads when the additional propellant tank is being jettisoned.
It was a problem with that upper stage which resulted in the loss of the Ekspress-AM4 communications satellite last month – which was not an ILS mission – when the stage, otherwise known as the Briz-M, failed to insert the satellite into the correct transfer orbit due to a problem with the last of the mission profile burns.
A Russian government launch using the Proton-M and Briz-M has since successfully returned the duo to launch action ahead of the ILS mission.
Once again, the mission utilizing a 5-burn Breeze M profile after lift-off from Pad 39 at Baikonur Cosmodrome, Kazakhstan, with the QuetzSat-1 satellite on board.
The first three stages of the Proton used a standard ascent profile to place the orbital unit (Breeze M upper stage and the QuetzSat-1 satellite) into a sub-orbital trajectory. From this point in the mission, the Breeze M performed planned mission maneuvers to advance the orbital unit first to a circular parking orbit, then to an intermediate orbit, followed by a transfer orbit, and finally to a geosynchronous transfer orbit.
Separation of the QuetzSat-1 satellite was successful and on schedule, approximately 9 hours, 13 minutes after liftoff.
QuetzSat-1, part of the 45+ satellite fleet of SES, will be located at the 77 degree west orbital location at which the Mexican Government has granted the DTH frequency rights to QuetzSat S. de R.L. de C.V., a Mexican-controlled company comprised of SES and Mexican investors.
The spacecraft will provide coverage over Mexico, North America and Central America. The spacecraft is fully contracted to EchoStar Corporation and will be used in part by Dish Mexico, an EchoStar joint venture, for DTH services in Mexico and to a subsidiary of DISH Network for use in connection with its U.S. DTH business.
Sporting 32 Ku-band transponders, the spacecraft is expected to conduct a 15 year tour of duty in its Geostationary orbit at 77 degrees West.
“ILS is dedicated to the success of SES and its customer, EchoStar, with the selection of ILS Proton to launch QuetzSat-1,” said Frank McKenna, President of ILS. “This is the fourth SES satellite entrusted to ILS this year, and we look forward to providing outstanding quality, service and schedule assurance to support the continued growth of the SES satellite fleet.”
“We are pleased that ILS is partnering with SES, Space Systems/Loral and EchoStar in the QuetzSat-1 mission and look forward to a flawless, on-time and on-spec launch for QuetzSat-1 with ILS Proton,” added Martin Halliwell, President of SES ENGINEERING, the procurement and operations division of SES.
The launch was the third ILS Proton launch in 2011, the 67th ILS Proton launch overall. The mission was also the 19th SES bird to be launched on an ILS Proton.
(Images: Roscosmos, ILS)