A communications satellite developed in a public-private partnership between Luxembourg government and SES is set for launch Tuesday aboard a previously-flown SpaceX Falcon 9 booster from Cape Canaveral, ready for a 15-year mission beaming encrypted, jam-resistant signals for security and military forces across Europe, Africa and the Middle East.
The GovSat 1 communications craft, manufactured by Orbital ATK, is heading for a high-altitude “supersynchronous” transfer orbit stretching tens of thousands of miles above Earth. The satellite will use its on-board engine to shift its orbit over the equator and slide into a perch in geostationary orbit at 21.5 degrees east longitude.
From there, GovSat 1’s Ka-band and X-band telecom equipment will relay data, radio signals and other communications across a zone stretching from the Atlantic Ocean to the Indian Ocean. Parked in geostationary orbit, GovSat 1 will move around Earth in lock-step with the planet’s rotation, giving it a fixed geographic coverage range.
Owned by LuxGovSat, a public-private joint venture between SES and the government of Luxembourg, GovSat 1 will provide military units deployed by NATO allies secure communications links via fixed land positions or antennas on ships in the Mediterranean Sea, the Baltic Sea, and the Atlantic and Indian Oceans.
“GovSat 1 is basically a dual-mission satellite, so it has two prime missions,” said Patrick Biewer, GovSat’s CEO. “One is a military Ka-band mission and the next one is an X-band mission. We provide secure communications services to our users, which can be found in the defense environment and the civilian security type usage.”
But the military-grade telecom satellite will first ride a SpaceX Falcon 9 rocket to orbit, a journey expected to take around 32 minutes.
The 9,325-pound (4,230-kilogram) GovSat 1 spacecraft is set for blastoff at 4:25 p.m. EST (2125 GMT) Tuesday from the Complex 40 launch pad at Cape Canaveral Air Force Station.
But brisk northerly winds are forecast in Central Florida for launch day, leading meteorologists at the U.S. Air Force’s 45th Weather Squadron to predict a 60 percent chance that conditions will prevent liftoff Tuesday.
“Skies will be partly cloudy on launch day with northerly winds gusting to 30 mph,” the 45th Weather Squadron wrote in an outlook issued Monday. “Winds will slowly diminish through the launch window. The primary concern is liftoff winds.”
The forecast for Tuesday evening calls for northerly winds of 25 to 30 mph, mostly clear skies and a temperature of 60 degrees Fahrenheit.
If conditions at the opening of the launch window are unfavorable, SpaceX has until 6:46 p.m. EST (2346 GMT) — after sunset — to launch the Falcon 9 rocket, or else wait until an identical launch window Wednesday, when lighter winds are predicted.
Tuesday’s mission will use a recycled Falcon 9 first stage recovered after the launch of a classified National Reconnaissance Office spy satellite codenamed NROL-76 on May 1, 2017.
It will be the sixth time SpaceX has re-flown one of its Falcon 9 booster stages, and the third time an SES telecom satellite has launched on a reused Falcon 9 first stage.
SpaceX says it will not attempt to recover the Falcon 9 booster on Tuesday’s flight.
The high-altitude orbit targeted by GovSat 1 will not leave the first stage with enough leftover fuel to return to a touchdown at Cape Canaveral, and the offshore landing platform typically used by SpaceX is being prepped for the maiden flight of the company’s Falcon Heavy rocket as soon as Feb. 6.
The Falcon Heavy’s two side boosters, modified from Falcon 9 first stages, will descend to landings at Cape Canaveral, while the Falcon Heavy’s central core will head for landing on SpaceX’s drone ship in the Atlantic Ocean.
Engineers accomplished a hold-down engine firing of the Falcon 9 rocket Friday at launch pad 40, then rolled the launcher back to its hangar for attachment of the GovSat 1 payload.
The rocket is expected to return to pad 40 overnight ahead of Tuesday’s countdown.
SpaceX’s launch team will load super-chilled, densified RP-1 kerosene fuel and liquid oxygen into the two-stage Falcon 9 rocket about an hour before liftoff.
Powered by 1.7 million pounds of thrust from nine Merlin 1D main engines, the 229-foot-tall (70-meter) Falcon 9 rocket will turn east to climb into the stratosphere over the Atlantic Ocean. The booster will exceed the speed of sound in about one minute, and its first stage will shut down at T+plus 2 minutes, 38 seconds, then drop away two seconds later.
A Merlin engine fitted with an extended nozzle for better performance in the vacuum of space will ignite at T+plus 2 minutes, 41 seconds, followed by the jettison of the Falcon 9’s nose shroud at T+plus 3 minutes, 44 seconds.
The second stage engine will switch off at T+plus 8 minutes, 35 seconds, after reaching a preliminary parking orbit with GovSat 1. Another critical second stage burn will begin at T+plus 26 minutes, 40 seconds, and last approximately 68 seconds.
The second upper stage firing will use up nearly all the engine’s propellant, using a guidance programming logic dubbed “minimum residual shutdown” mode to send GovSat 1 into the highest orbit possible. The high-altitude deployment into an elliptical transfer orbit is aimed at minimizing the fuel GovSat 1 needs to consume to maneuver into its final orbital perch.
Separation of GovSat 1, also known as SES 16, is expected at T+plus 32 minutes, 19 seconds, over Africa.
The launch of GovSat 1 marks the fifth time an SES satellite has launched on a SpaceX Falcon 9 rocket. It will be the fourth Orbital ATK-built spacecraft to fly on a Falcon 9 launcher.
GovSat 1 will fire an on-board thruster several times to circularize its orbit more than 22,000 miles (nearly 36,000 kilometers) over the equator. Within a few weeks, the satellite should be on station for in-orbit checkouts, and communications services from GovSat 1 should begin soon after that.
The satellite project was financed with 100 million euros ($123 million) invested in a 50-50 shareholder arrangement between SES and the Luxembourg government, plus a 125 million euro ($154 million) loan from a consortium of Luxembourg banks.
The startup investments and loan covered LuxGovSat’s founding costs, and the procurement of the GovSat 1 spacecraft and its launch on a Falcon 9 rocket.
“GovSat is the first public-private venture that operates satellite communications services in governmental frequencies,” Biewer said. “It’s been set up between two shareholders as a public-private venture, at one end it’s SES providing the technical competence and on the other side is the Luxembourg government, who has the ambitions to develop a new proposition in defense communications services.”
SES operates the biggest commercial satellite fleet in geostationary orbit, and Tuesday’s launch will be the second for the company in five days. The SES 14 telecom craft lifted off Thursday aboard a European Ariane 5 rocket, which put the satellite in an off-target orbit, ending a streak of 82 flawless Ariane 5 flights in a row.
SES 14 will still accomplish its mission, SES officials said, and will use its plasma thrusters to reach its operational orbit around four weeks later than originally planned.
The Ariane 5 rocket also launched with the Orbital ATK-built Al Yah 3 communications satellite for Abu Dhabi-based Yahsat. Like Al Yah 3, GovSat 1 is based on Orbital ATK’s new GEOStar 3 spacecraft chassis, a larger, more powerful version of the manufacturer’s previous line of telecom craft.
The Luxembourg government has pre-committed to purchase a significant amount of GovSat 1’s total communications capacity. Officials will make the rest of the telecom relay capability available to Luxembourg’s NATO allies.
GovSat says the spacecraft’s X-band frequency is tailored for “secure and robust satellite communication links.” Examples include data relays between tactical theaters, maritime missions, or regions impacted by humanitarian crises.
The Ka-band payload is suited for communications on-the-move, broadcasting to smaller antenna terminals aboard ships, airplanes and other mobile vehicles. One of GovSat 1’s Ka-band beams is focused on the Mediterranean Sea to aid European border service patrols.
GovSat 1 carries a global X-band beam with coverage extending from the Atlantic Ocean to India, and from Scandinavia to South Africa.
Controllers can manipulate six steerable high-power beams on GovSat 1 to support operations across the satellite’s coverage area.
“We have a number of security capabilities on the satellite,” Biewer said. “This includes anti-jamming, for instance, it also includes command and control encryption. Overall, we provide a total capacity equivalent to roughly 68 transponders. GovSat 1 features a total of six steerable beams that can be easily operated in military Ka-band or X-band. It also has a global wide beam operated in X-band.
“The government is providing access to these governmental frequencies, and the government also provides the necessary stability — the trust — for us and for partners and users we are targeting.”
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