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SpaceX launches mission to US space forces for the first time-Now Spaceflight



The Falcon 9 rocket exploded in the 40th airspace at Cape Canaveral Air Force Base in Florida on Tuesday. Credit: SpaceX

On Tuesday, a new GPS satellite was launched into orbit from a SpaceX Falcon 9 launcher from Cape Canaveral to replace one of the more than 30 other spacecraft, helping guide from military ammunition to All activities of the driver.

This is SpaceXs’ first launch for the US Space Force. After the establishment of a new military unit in December, the project took over most of the space projects operated by the Air Force. The third in a new series of upgraded GPS navigation satellites flying the Falcon 9 rocket adds new functionality to the GPS network and replaces the aging spacecraft launched more than 20 years ago.

“GPS 3 plans to continue to build on its success by providing the US space forces with advanced features and maintaining the “gold standard” of position, navigation, and timing.” Edward, the head of the Center for Orbital Space Systems Department of the Space and Missile Systems Center · Colonel Byrne said.

The third GPS 3 series satellite is called GPS 3 SV03 and took off at 4:10:46 PM. EDT (2010: 46 GMT) is from the 40th pad of Cape Canaveral Air Force Base in Florida.

The 9,505-pound (4,311 kg) spacecraft flew 229 feet high (70 meters) from the Falcon 9 rocket and flew northeast from Cape Canaveral and was roughly parallel to the east coast of the United States.

Nearly 90 minutes after launch, the upper layer of the Falcon 9 accurately released the GPS 3 SV03 satellite into the target transfer orbit at an altitude of between 250 miles (400 kilometers) and 12,550 miles (20,200 kilometers) with an inclination of 55 degrees to the equator

On-time orbit will enable the GPS 3 SV03 spacecraft to use its own propulsion system in the next few weeks to orbit it at an altitude of 12,550 miles. The satellite will enter the operational GPS constellation as early as August, the officer said.

The launch was originally scheduled for late April, but military officials delayed the flight by two months to allow the Colorado Satellite Operations Center team time to introduce and test the new protocol to achieve the physical distance between the consoles. According to Byrne, officials reduced the size of personnel inside the control center, increased zoning and purchased personal protective equipment for satellite controllers to reduce the risk of a coronavirus pandemic.

The GPS 3 SV03 satellite manufactured by Lockheed Martin will be put into use in the fourth slot E plane of the GPS constellation. The location is currently occupied by a GPS satellite launched from the Delta 2 rocket launched from Cape Canaveral on May 10, 2000. Military officials did not say whether the satellite originally scheduled for a ten-year mission would be retired or moved to another slot on the GPS network.

Lockheed Martin confirmed in a statement after its launch on Tuesday that the GPS 3 SV03 spacecraft is responding to orders from engineers at the company’s launch and inspection center in Denver.

GPS satellites are distributed on six orbital aircraft, each of which has four main spacecraft and spare parts. Byrne said in a conference call with reporters last Friday that the GPS constellation currently consists of 31 satellites.

The GPS network provides positioning and timing services for military and civilian users worldwide. Among many other users, passenger planes, ATMs, drivers and smart bombs also rely on this signal.

Tonya Ladwig, Acting Vice President of Lockheed Martin’s Navigation Systems Division, said: “GPS has become part of our critical national infrastructure, from transportation to financial markets, to the energy grid to the ride-sharing industry, “GPS is no longer used today. It really depends on how many times you actually use it.”

The GPS network is estimated to have 4 billion users and reached full operational capacity in 1995. Since then, the military has conducted a series of launches to supplement the GPS satellite fleet with ULA’s Atlas and Delta rockets and now SpaceX’s Falcon 9.

The GPS 3 satellite provides more accurate navigation signals and has a longer design life of 15 years. The new GPS 3 satellite also broadcasts a new L1C civilian signal that is compatible with the Galileo network in Europe and the quasi-zenith satellite system in Japan.

Military officials say that the compatibility of GPS signals with satellite navigation networks operated by allies can maximize the accuracy of positioning and timing signals, thereby helping to ensure that users can fix their positions with more spaceships at once.

The US military’s third GPS 3 series satellite, named SV03, is ready to be packaged in the payload fairing of its SpaceX-made Falcon 9 rocket. Credit: SpaceX

Like the first few GPS 2F satellites manufactured by Boeing, all GPS 3 series spacecraft broadcast L5 signals dedicated to supporting air navigation. GPS 3 satellites also continue to transmit encrypted military-grade navigation signals, or M codes.

The M code signal allows GPS satellites to broadcast higher power, anti-jamming signals in specific areas (such as military battlefields or battlefields). This function provides more reliable navigation services for the US and Allied forces, and also allows the military to intentionally interfere with or interfere with civilian GPS signals in specific areas, while the M code signal is not obstructed.

L3Harris Technologies builds navigation payloads for GPS 3 satellites.

The first two GPS 3 series satellites were launched on the SpaceX Falcon 9 rocket in December 2018, and were launched on the United Launch Alliance Delta 4 booster in August last year. Both announced full operation early this year.

Radvig said that the GPS 3 SV04 and SV05 spacecraft have been completed and are in storage and are waiting for launch. The next three satellites have been fully assembled and are undergoing environmental testing. The SV09 and SV10 are currently being assembled at Lockheed Martin’s GPS satellite factory near Denver.

Lockheed Martin has a contract with the Ministry of Defense to manufacture 10 GPS 3 satellites, two of which have been launched, and up to 22 upgraded GPS 3F series satellites.

The space forces have reserved the next three GPS 3 series satellites launched with SpaceX. An SMC spokesman said that the GPS SV04 mission is scheduled to be released on September 30, and then SV05 will be released in January 2021.

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

The Falcon 9 booster touched SpaceX’s drone “Just Read the Instructions”, which is located about 400 miles (630 kilometers) northeast of Cape Canaveral in the Atlantic Ocean.

After separating from the Falcon 9’s superior, the first stage fired the engine, guided itself to the drone ship, and executed for about two and a half minutes. Titanium fins helped stabilize the rocket during the descent, and the booster landed on the power of its central engine approximately eight and a half minutes after launch.

For SpaceX, this is a crucial recovery, and its purpose is to reuse the booster in future flights. The first stage used on Tuesday is a brand new booster.

Mission planners modified the Falcon 9 launch configuration to accommodate booster landings.

Walter Lauderdale, head of the launch mission for GPS SV03, said that the launch configuration adjustments made to land the Falcon 9 booster ultimately saved the military from the initial SpaceX launch contract worth $96.5 million. Millions of dollars”. Force Space and Missile System Center.

When SpaceX first launched a GPS navigation satellite in December 2018, military officials asked the launch company to use the full capabilities of the Falcon 9 rocket to put the spacecraft into orbit. This means that SpaceX cannot install the take-off and landing legs in the first phase of Falcon 9, nor can it attempt to recover the booster.

To reduce costs, SpaceX landed, refurbished and re-boarded the Falcon 9 aircraft, which is the only launch company that can currently reuse rocket hardware.

SpaceX has recovered rockets with military payloads in previous launches, such as the heavy-duty “Falcon” mission in June last year, but these missions carried experimental technology demonstrations and research satellites, rather than GPS satellites. Run the spacecraft.

When SpaceX first launched GPS in 2018, the military asked the Falcon 9 rocket to send the spacecraft into orbit beyond 740 miles (approximately 1,200 kilometers) at high and low points (or low points). The team also added additional fuel to the GPS spacecraft, just in case.

It is the first high-priority national security payload launched using the SpaceX rocket and the first satellite in the design of a new GPS spacecraft.

Lauderdale said: “In short, given the trajectory of the mission and the weight of the payload, plus the uncertainty of the mission, the performance is insufficient.”

Lauderdale said: “Our assessment of mission performance, coupled with SpaceX’s additional work, has reduced uncertainty in many areas.” “When we contacted SpaceX to modify certain spacecraft requirements for this mission… they In response, there was an opportunity to withdraw the booster in exchange for increasing these requirements and other considerations.”

The artist’s vision of the GPS 3 satellite in space. Credit: Lockheed Martin

Now officials are more satisfied with the performance of the Falcon 9 rocket and the new GPS 3 series satellite design. This allows engineers to load less propellant into the third GPS 3 satellite.

Byrne said the mission planner also changed the initial orbit of the spacecraft after launch from 740 miles to 250 miles.

Byrne said in a conference call before the press conference with reporters: “All we need is to reassess our combustion situation, so we made some minor modifications to the combustion situation, but there is no task related to booster recovery options. influences.”

A change to the Falcon 9 rocket used for the GPS SV03 mission is the gray thermal insulation layer above the launcher. The thermally conductive layer is designed to maintain kerosene fuel at an appropriate temperature during the nearly one hour coasting between the first and second combustions of the superior Merlin engine, and then several inertias before the third Merlin The taxi phase keeps the propellant stable. Burning took the stage off track.

SpaceX has previously tested the thermosphere, but did not fly in the first GPS 3 launch in 2018. The company has conducted trials on the long coast above Falcon to collect data before launching the national security payload specifically for the first time. In the second half of this year, SpaceX’s three-core Falcon Heavy rocket.

Since Falcon 9 first launched GPS satellites in 2018, military engineers responsible for the design and production of SpaceX rockets that oversee national security missions have evaluated many configuration changes.

Lauderdale said: “Since the launch of GPS 3 in December 2018, we have been working with SpaceX to maintain the latest configuration of Falcon 9 and evaluate 665 changes.” “This allows us to maintain the vehicle technical benchmark, which is our The basis for independent mission assurance.”

Space force officials have not yet approved SpaceX to use previously-flighted boosters to launch key military satellites-a class of missions called “national security space launch” payloads. To date, SpaceX has relaunched Falcon boosters 37 times, achieving a 100% success record.

Lauderdale said the SMC mission assurance team is becoming more familiar with how SpaceX refurbished rockets between flights.

He said Friday: “I can’t guarantee when we will be ready.” He refers to when the military can launch a national security payload on a reusable Falcon 9 booster.

SpaceX is building a brand new Falcon Heavy rocket for national security launches later this year, and the company is expected to use a brand new booster for its next GPS launch by September 30.

The military is currently considering proposals from the four companies SpaceX, ULA, Blue Origin and Northrop Grumman in the next round of procurement of launch services. Lauderdale said the military will allow launch service providers who have won so-called “second-stage” contracts to launch rockets for national security space for repeated use to reduce costs.

Lauderdale said: “As a plan, we are open, ready, and looking forward to what any industry wants to provide us, but mainly because we have always regarded the second stage of competition as an opportunity.”

After the launch of the Global Positioning System (GPS), the SpaceX team on the Florida coast will once again turn its attention to launching the Falcon 9 rocket pad 39A at NASA Kennedy Space Center and the next batch of SpaceX’s Starlink Internet satellites.

The mission was originally scheduled for launch on Friday, June 26, but SpaceX scrubbed the launch attempt and postponed the flight until the GPS launched from a nearby pad 40. The warning notice for the launch hazard zone issued by sailors near the Florida Space Coast on Tuesday suggested the use of the next Falcon 9. / The release time of Starlink has been changed to July 8 (Wednesday).

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Follow Stephen Clark on Twitter: @ StephenClark1.




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