17.02.2021

SpaceX plans two Falcon Heavy launches this year for the U.S. Space Force in July and October, and United Launch Alliance has four national security space missions on its 2021 schedule, according to a military spokesperson.

The Falcon Heavy missions are expected to be the fourth and fifth flights of SpaceX’s triple-core heavy-lifter. Both launches will take off from pad 39A at the Kennedy Space Center in Florida.

The first Space Force mission on a Falcon Heavy rocket this year is designated USSF-44. The mission is scheduled for launch in July, according to a Space Force spokesperson. The USSF-44 mission will be the fourth flight of a Falcon Heavy since its debut in February 2018.

The Falcon Heavy will deliver multiple military payloads to a high-altitude geosynchronous orbit on the USSF-44 mission. The rocket’s upper stage will fire several times to place the satellites into position more than 22,000 miles above the equator.

The upper stage flight profile will include a coast lasting more than five hours between burns, making the USSF-44 mission one of SpaceX’s most demanding launches yet.

On the most recent Falcon Heavy mission, which lifted off in June 2019, the rocket’s upper stage completed four burns over three-and-a-half hours on a demonstration flight sponsored by the Air Force.

The complex orbital maneuvers during last June’s mission were required to place 24 satellite payloads into three distinct orbits. They also exercised the capabilities of the Falcon Heavy and its Merlin upper stage engine before the Air Force entrusts the launcher with more critical, and more expensive, operational national security payloads on future flights, such as the USSF-44 mission.

SpaceX won a contract for the USSF-44 launch in February 2019. In the request for proposals for the USSF-44 launch, the military told prospective launch providers to assume the combined mass of two payloads assigned to the mission is less than 8,200 pounds, or about 3.7 metric tons.

The Space Force hasn’t said whether there are still two satellites booked on the USSF-44 mission, or if officials added more secondary payloads since the 2019 contract award. One of the spacecraft on the USSF-44 launch is a microsatellite named TETRA 1 built by Millennium Space Systems, a subsidiary of Boeing headquartered in El Segundo, California.

Military officials said in a statement the TETRA 1 satellite was created to “prototype missions and tactics, techniques and procedures in and around geosynchronous Earth orbit.”

Another military launch on the Falcon Heavy, designated USSF-52, is scheduled no earlier than October, according to the Space Force. Military officials have not disclosed any payloads on the USSF-52 launch, but the Air Force wrote in a draft contract solicitation that the mission would deliver a heavy payload to a geostationary transfer orbit, an elongated path around Earth used as a drop-off point for many satellites heading to a circular geosynchronous orbit.

SpaceX has launched three Falcon Heavy rocket missions to date, all successfully. SpaceX has seven confirmed Falcon Heavy missions in its backlog, including the two Space Force missions this year, and launches of a Viasat broadband communications satellite and NASA’s Psyche asteroid explorer, both in 2022. A single Falcon Heavy will also launch the first two elements of NASA’s Gateway lunar space station in 2024, and two Falcon Heavy flights will boost Dragon XL cargo missions to the Gateway later in the 2020s.

The Space Force’s USSF-67 mission, awarded to SpaceX last year, may also launch on a Falcon Heavy. But military officials have not confirmed a rocket assignment for that mission.

The Falcon Heavy is made up of three modified Falcon 9 first stage boosters connected together in a triple-core configuration. The rocket’s 27 Merlin main engines produce some 5.1 million pounds of thrust at liftoff, more than any other currently operational rocket.

All of SpaceX’s Falcon Heavy missions currently under contract will take off from Kennedy Space Center in Florida, where the company plans to construct a vertical integration building and shelter to accommodate future Falcon Heavy payloads.

SpaceX will use three newly-manufactured boosters for the USSF-44 mission, and the challenging launch profile will leave no leftover propellant to recover the center core of the Falcon Heavy, according to the Space Force. The core stage will be expended on the launch, while the rocket’s two side boosters will be recovered on two SpaceX drone ships positioned downrange east of Cape Canaveral.

SpaceX has one more publicly-announced Space Force mission in its backlog this year. A Falcon 9 rocket is scheduled to launch from Cape Canaveral Space Force Station in July with the military’s fifth GPS 3-series navigation satellite. The launch of the sixth GPS 3 satellite, also on a Falcon 9, has been delayed into 2022, the Space Force said.

United Launch Alliance has four military space missions scheduled this year.

A Delta 4-Heavy rocket, ULA’s most powerful launcher, is being prepared for liftoff from Vandenberg Air Force Base in California as soon as this spring with a classified spy satellite cargo for the National Reconnaissance Office. The NROL-82 mission is one of four Delta 4-Heavy flights left before the rocket’s retirement in 2023.

Three Space Force missions will launch on ULA Atlas 5 rockets from Cape Canaveral this year.

The first of the Space Force launches, named STP-3, was supposed to launch this month. An Atlas 5 rocket will launch two experimental military satellites into geosynchronous orbit on the STP-3 mission, but one of the spacecraft encountered delays that caused it to miss its late February launch date.

Officials are assessing new potential launch dates in the middle of the year, according to Jim Reuter, head of NASA’s space technology mission directorate, which is flying a laser communications experiment on the STP-3 mission.

The STP-3 mission will use the most powerful variant of the Atlas 5 rocket, known as the “551” configuration, with five strap-on solid rocket boosters and a 5-meter-diameter payload shroud.

In the May timeframe, an Atlas 5 rocket is scheduled to launch with the Space Force’s fifth Space-Based Infrared System, or SBIRS, satellite to detect missile launches that could threaten the United States. The Lockheed Martin-built SBIRS GEO 5 satellite will ride into orbit on an Atlas 5 “421” with a 4-meter-diameter payload fairing and two solid rocket boosters.

Another Atlas 5 is scheduled to launch in August with the USSF-8 mission, which will deliver the Space Force’s fifth and sixth Geosynchronous Space Situational Awareness Program, or GSSAP, satellites into orbit.

The USSF-8 mission will use the Atlas 5-511 configuration with a 5-meter fairing and a single solid rocket booster. It will be the first time the “511” variant of the Atlas 5 has flown.

Quelle: SN