Home / Science / SpaceX launches its first mission for the U.S. Space Force – Spaceflight Now

SpaceX launches its first mission for the U.S. Space Force – Spaceflight Now



A Falcon 9 rocket departs Tuesday from pad 40 at the Cape Canaveral Air Force Station, Florida. Credit: SpaceX

A new GPS satellite shot into orbit from Cape Canaveral on top of a SpaceX Falcon 9 launcher on Tuesday on the way to replace one of the more than 30 other spacecraft that help guide everything from military ammunition to motorists.

The launch was the first by SpaceXs for the US Space Force, which took over most of the space programs managed by the Air Force after its establishment as a new military service in December. The third of a new line of navigation satellites of the updated global positioning system flew aboard the Falcon 9 rocket, adding new features to the GPS network and replacing an obsolete spacecraft launched over 20 years ago.

“The GPS 3 program continues to leverage its success by providing advanced functionality for the United States Space Force and maintaining the” reference standard “for location, navigation and timing.” said Colonel Edward Byrne, head of the division of space systems in medium Earth orbit at the Space and Missile Center.

The third GPS series 3 satellite, designated GPS 3 SV03, took off at 16:10:46 EDT (2010: 46 GMT) from pad 40 at the Cape Canaveral Air Force Station in Florida.

Riding a 70-meter (229-foot) high Falcon 9 rocket, the 9,505-pound (4,311 kilogram) spacecraft launched a trajectory northeast from Cape Canaveral, flying roughly parallel to the east coast of the United States.

Almost 90 minutes after take-off, Falcon 9’s upper stage accurately released the GPS 3 SV03 satellite in a target transfer orbit that varies in height between approximately 250 miles (400 kilometers) and 12,550 miles (20,200 kilometers), with an inclination of 55 degrees to the equator.

The spot-on orbit puts the GPS 3 SV03 spacecraft in position to use its propulsion system in the coming weeks to circulate the orbit at an altitude of 12,550 miles, where the satellite is set to enter the operational GPS constellation already in August, military officials said.

The launch was originally scheduled for late April, but military officials delayed the flight by two months to allow teams from a satellite operations center in Colorado to introduce and test new protocols to allow for physical spacing between the control consoles. Officials reduced the size of the crew inside the control center, and added partitions and provided personal protective equipment for satellite controllers to reduce the risks in the coronavirus pandemic, according to Byrne.

Manufactured by Lockheed Martin, the GPS satellite 3 SV03 is set up to enter service in plane E, slot 4 of the GPS constellation. This position is currently occupied by a GPS satellite launched on 10 May 2000 by Cape Canaveral on a Delta 2 rocket. Military officials have not said whether that satellite, which was originally designed for a 10-year mission, would have been withdrawn or moved to another slot on the GPS network.

Lockheed Martin confirmed in a statement after Tuesday’s launch that the GPS 3 SV03 spacecraft was responding to engineer commands at the company’s Launch and Control Center in Denver.

GPS satellites are spread over six orbital planes, each with four primary spacecraft and parts. On Friday, Byrne said in a pre-launch teleconference with reporters that the GPS constellation is currently made up of 31 satellites.

The GPS network offers positioning and timing services worldwide for military and civilian users, beams of signals invoked by airliners, ATMs, drivers and smart bombs, among numerous other users.

“The global positioning system has become part of our critical national infrastructure, from transportation to financial markets, from energy networks to the rideshare industry,” said Tonya Ladwig, vice president of the navigation systems division of Lockheed Martin. “You haven’t used GPS today. It depends on how many times you have actually used it.”

With around 4 billion users, the GPS network reached full operational capacity in 1995. The military has conducted a series of launches to supply the GPS satellite fleet ever since, using the Atlas and Delta rockets of the ULA and now Falcon 9 of SpaceX.

GPS 3 satellites provide more precise navigation signals and have a longer design life than 15 years. The new GPS 3 satellites also transmit a new L1C civil signal compatible with the European Galileo network and Japan’s Quasi-Zenith satellite system.

Military officials say that the compatibility of GPS signals with satellite navigation networks operated by the Allies maximizes the accuracy of positioning and timing signals, helping to ensure that users can repair their positions through multiple spacecraft in the sky simultaneously.

The U.S. Army’s third GPS 3 series satellite, designated SV03, is ready to encapsulate the payload of its SpaceX-built Falcon 9 rocket inside the fairing. Credit: SpaceX

Like the previous line of GPS 2F satellites built by Boeing, all GPS 3 series spacecraft transmit a dedicated L5 signal oriented to support air navigation. GPS 3 satellites also continue to transmit a military-grade encrypted navigation signal known as an M-code.

The M-code signal allows GPS satellites to transmit high-power, jam-resistant signals to specific regions, such as a military theater or battlefield. The capability provides the United States and allied forces with more reliable navigation services and could also allow military personnel to intentionally stop or block civilian-level GPS signals in a particular region, while the M-code signal remains free.

L3Harris Technologies builds navigation payloads for GPS 3 satellites.

The first two Series 3 GPS satellites launched in December 2018 on a SpaceX Falcon 9 rocket and last August aboard a United Launch Alliance Delta 4 booster. Both were declared fully operational earlier this year.

Ladwig said that the GPS 3 SV04 and SV05 spacecraft are complete and in storage pending launch, and the next three satellites are fully assembled and environmental tested. SV09 and SV10 are currently being assembled at the Lockheed Martin GPS satellite factory near Denver.

Lockheed Martin has a contract with the Department of Defense to build 10 GPS 3 satellites – two of which have been launched – and up to 22 updated 3F GPS satellites.

Space Force has reserved the next three series 3 GPS satellite launches with SpaceX. An SMC spokesman said the SV04 GPS mission is slated to launch no earlier than September 30, followed by SV05 in January 2021.

Tuesday’s launch also marked the first time that military officials allowed SpaceX to reserve enough rocket propellant to land the Falcon 9 first stage booster after launching a high priority national security payload.

The Falcon 9 booster landed on the SpaceX drone ship “Just Read The Instructions” located approximately 400 miles (630 kilometers) north-east of Cape Canaveral in the Atlantic Ocean.

The first stage started its engines to drive itself towards the drone ship after the separation from the upper stage of Falcon 9 after about two and a half minutes from the mission. The fins of the titanium grill helped stabilize the rocket during the descent and the booster landed on the power of its mid-engine about eight and a half minutes after launch.

It was a crucial recovery for SpaceX, which aims to reuse the booster on a future flight. The first stage used on Tuesday was a brand new booster.

Mission planners changed Falcon 9’s launch profile to suit the booster’s landing.

Adjusting the launch profile to make it possible for Falcon 9’s repeater to land ended up saving “several million dollars” for the army from the original SpaceX launch contract value of $ 96.5 million, according to Walter Lauderdale, director of the SV03 GPS launch mission from the Force Space and Missile Center.

At the first launch of a GPS navigation satellite by SpaceX in December 2018, military officials asked the launch company to devote all the ability of the Falcon 9 rocket to put the spacecraft into orbit. This meant that SpaceX could not install the landing legs on the first stage of Falcon 9 or attempt to recover the booster.

SpaceX lands, renews and flies the early stages of Falcon 9 again to cut costs, and is the only launch company that currently reuses missile hardware.

SpaceX recovered missiles on previous launches with military payloads, such as a Falcon Heavy mission last June, but those missions carried experimental technological demonstrations and research satellites – not operational spacecraft such as a GPS satellite.

At the first GPS launch of SpaceX in 2018, the army requested the Falcon 9 rocket to position the spacecraft in an orbit with a higher perigee, or low point, of over 740 miles, or about 1,200 kilometers. The teams also loaded extra fuel into the GPS spacecraft as an additional precaution.

It was the first high priority national security payload to be launched on a SpaceX rocket and it was also the first satellite in a new GPS spacecraft design.

“Put simply, there was insufficient performance given the trajectory of the mission and the weight of the payload, combined with the uncertainties associated with this challenging mission,” said Lauderdale.

“Our assessment of that mission’s performance, combined with additional work with SpaceX, reduced uncertainty in many areas,” said Lauderdale. “When we approached SpaceX to review some spacecraft requirements for this mission … they responded with the opportunity to recover the booster in exchange for adding these requirements, as well as other considerations.”

The artist’s concept of a GPS 3 satellite in space. Credit: Lockheed Martin

Officials are now more comfortable with the performance of the Falcon 9 rocket and the new GPS 3 series satellite design. This has allowed engineers to load less propellant into the third GPS 3 satellite.

Mission planners also changed the perigee of the spacecraft’s initial orbit after launch from approximately 740 miles to 250 miles, according to Byrne.

“All we were asked for was to reevaluate our burn profile, so we made some minor changes to that burn profile, but there was no impact on the mission associated with the booster recovery option,” he said. Byrne in a pre-launch conference call with reporters.

A modification to the Falcon 9 rocket for the SV03 GPS mission was a gray strip of thermal insulation on the launcher’s upper stage. The thermal layer was designed to help keep the kerosene fuel at adequate temperatures during a coasting phase of almost an hour between the first and second burns of the Merlin engine of the upper stage, and therefore to keep the propellants stable during a another coast phase of several hours before a third Merlin burns to deorb the stage.

SpaceX has already tested the thermal layer previously, but has not flown on the first GPS 3 launch in 2018. The company experimented with long-lasting ribs from the upper Falcon phase to collect data before the first dedicated launch of a national security payload on SpaceX’s triple-core Falcon Heavy rocket later this year.

Military engineers in charge of overseeing the design and production of SpaceX missiles for national security missions have evaluated numerous configuration changes since Falcon 9’s first launch of a GPS satellite in 2018.

“Since the launch of GPS 3 in December 2018, we have partnered with SpaceX to stay updated on the Falcon 9 configuration, evaluating 665 changes,” said Lauderdale. “This allowed us to maintain the technical base of the vehicle that underpins our independent mission insurance.”

Space Force officials have not yet approved SpaceX for the launch of critical military satellites – a mission class known as the National Security Space launch payload – using previously piloted boosters. SpaceX has relaunched Falcon’s repeaters 37 times to date with a 100% success record.

Lauderdale said the SMC mission insurance team is becoming more familiar with the way SpaceX renews missiles between flights.

“I can’t commit to when we’re ready,” he said on Friday, referring to when the military could launch a national security payload on a reused Falcon 9 repeater.

SpaceX is building a brand new Falcon Heavy rocket for a national security launch later this year, and the company is expected to use a brand new booster for the next GPS launch no earlier than September 30th.

The army is currently evaluating proposals from four companies – SpaceX, ULA, Blue Origin and Northrop Grumman – in the next round of launch service contracts. Lauderdale said the military would allow launch service providers who win so-called “Phase 2” contracts to offer reused missiles for national security clearance launches in an attempt to cut costs.

“As a program, we are open and ready and we are looking forward to the industry wanting to make ourselves available, but mainly we have considered Phase 2 competition as an opportunity,” said Lauderdale.

With the launch of GPS behind them, SpaceX teams on the Florida Space Coast will again turn their attention to launching a Falcon 9 39A rocket at NASA’s Kennedy Space Center with SpaceX’s next batch of Starlink Internet satellites.

That mission should have been launched on Friday June 26, but SpaceX canceled the launch attempt and postponed the flight until after the launch of the GPS from nearby pad 40. A warning in the launch area released on Tuesday for sailors offshore of the Florida space coast suggested the next Falcon 9 / The launch of Starlink has been rescheduled for Wednesday, July 8.

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Follow Stephen Clark on Twitter: @ StephenClark1.




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