After two successful Falcon Heavy missions in less than 11 weeks, launch fans will likely have to wait until the end of 2020 for SpaceX's next Falcon Heavy flight, a surprise mission for an unannounced customer.
SpaceX has successfully launched Falcon Heavy missions – successfully – and has fixed launch contracts or contract options for four Falcon Heavy missions along with the US Air Force, Viasat and Inmarsat. All missions are expected to take off from the launch plate 39A at NASA's Kennedy Space Center in Florida, the only facility equipped to accommodate the triple Falcon Heavy rocket.
One of the Air Force missions, designated AFSPC-44, is next in line to fly on a Falcon Heavy rocket. The AFSPC-44 mission is scheduled for launch in autumn 2020, according to colleague Robert Bongiovi, head of the launch company system directorate at the Air Force Space and Missile Systems Center.
The Air Force has not identified the payloads on the AFSPC-44 mission, which the military assigned SpaceX Falcon Heavy in February. Documents released with the military's request for suggestion indicate that the AFSPC-44 launch will accommodate two payloads in a circular geosynchronous path more than 22,000 miles across the equator.
In the inquiry application, the Air Force told that potential launch suppliers assume that the combined mass of the two payloads is less than £ 8,200, or about 3.7 tonnes.
A direct injection of the AFSPC-44 satellites into the geosynchronous path of the Falcon Heavy rocket requires a long coastal phase of more than five hours between upper stage motor burns. On the latest Falcon Heavy mission, which lifted Tuesday, 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 were required to place the mission's 24 satellite loads in three distinct paths. They also exercised the capacity of Falcon Heavy and its Merlin top stage engine before the Air Force entrusts the starter with more critical and more expensive, operational national security loads on future flights.
The Air Force formally certified Falcon Heavy to be eligible to win national security launch contracts after the rocket's initial flight last year. A number of in-depth technical and process reviews are now in progress before the military places a critical national safety satellite on a Falcon Heavy.
"What we are doing now is what we call the spaceflight's dignity process," Bongiovi said in a pre-launch conference call with reporters.
The successful STP-2 mission "will move us one step closer to spaceflight dignity for the AFSPC-44 launch in the autumn of 2020," Bongiovi said before launch.
The Falcon Heavy used on the STP-2 mission flew with reused sidestones that were restored after the previous Falcon Heavy launch on April 11, which delivered the commercial Arabsat 6A communication to orbit.
Officials said they will use the experience of the STP-2 mission to familiarize air force engineers with SpaceX's booster recovery and re-use procedures to help certify previously floated rocket hardware for national security missions. Prior to the STP-2 launch, all the Air Force has been launched with SpaceX so far using newly built Falcon 9 boosters.
After the AFSPC-44 launch, the Air Force is planning another Falcon Heavy mission with SpaceX in the spring of 2021, Bongiovi said. The launch, named AFSPC-52, was previously scheduled to take off in September 2020, but in a briefing with reporters earlier this month, Bongiovi twice said the AFSPC-44 mission is Air Force's next Falcon Heavy mission.
Like the AFSPC-44 launch, the Air Force has not identified the name or purpose of the payload to be launched on the AFSPC-52 mission.
In a draft call that was released for the AFSPC-52 mission, the Air Force said that the payload required a lifting capacity of around £ 14,000, or 6,350 kg, for a geostationary transmission line extending between 115 miles (185 kilometers) and 21,865 miles (35,188 kilometers) ), with a gradient of 27 degrees.
Viasat and Inmarsat are the two largest telecom operators with contracts or alternatives to fly their payload on a Falcon Heavy rocket.
SpaceX won a contract with Viasat last year to launch one of the broadband provider's three next generation communications satellites on a Falcon Heavy. Viasat develops three new Boeing-built satellites, known as the ViaSat 3 fleet, to expand the company's broadband Internet coverage around the world, with spacecraft deployed across America, Europe, Africa and the Middle East and across the Asia-Pacific region.
Viasat has booked fixed launch contracts with SpaceX, United Launch Alliance and Arianespace to carry a ViaSat 3 satellite at a time against its operational positions in geostationary orbit that began in 2021. But the California-based broadband company has not announced the order for ViaSat 3 launches, or rocket starts every satellite.
Viasat said Falcon Heavy will place its satellite "extremely close" to its final perch in geostationary orbit, with a multi-hour launch profile similar to that planned for the AFSPC-44 mission.
London-based Inmarsat also has a contract alternative with SpaceX for a Falcon Heavy launch. After delays in Falcon Heavy's first flight, Inmarsat decided to change the launch of one of its satellites in 2017 to a Falcon 9 rocket, but retained a contract alternative to fly a satellite to a future Falcon Heavy Mission.
Inmarsat, which owns a network of satellites for maritime and aviation communications, has not implemented the Falcon Heavy Contract option. Inmarsat's CEO said in March that one of the company's future satellites – Airbus-created Inmarsat 6B spacecraft planned for launch at the end of 2021 – may be a candidate to fill the company's Falcon Heavy contract options, according to Space News.
SpaceX has also announced an extra customer to start a satellite on a Falcon Heavy Mission.
The Swedish company Ovzon announced last year its choice of a Falcon Heavy rocket to pull its first geostationary communication satellite into circulation. Ovzon announced that the satellite would ride Falcon Heavy directly in geostationary orbit.
Depending on the final financing, the Ovzon 3 satellite will be built by Maxar's SSL division and is expected to weigh less than one ton at the launch. The relatively light weight of the Ovzon 3 spacecraft suggests that it may not be a dedicated launch, and can fly with another payload on Falcon Heavy.
Several SpaceX missions have been announced only months in advance, such as the Falcon 9 launch of the US Air Force X-37B space plan in September 2017 and lift off the US government's mysterious Zuma payload in January 2018.
A Falcon 9 launch of a South Korean military communications satellite scheduled for November from Cape Canaveral also went unannounced until earlier this month.
Gwynne Shotwell, SpaceX's president and chief executive officer, said in May that the company is planning between 18 and 21 missions this year, with the exception of flights with SpaceX's own Starlink broadband satellite.
SpaceX has completed eight missions during the first half of the year, including a launch dedicated to the Starlink network.
Reply to a question about the next Falcon Heavy launch from Spaceflight Now, a SpaceX spokesman referred to the company's online manifesto, which does not list any Falcon Heavy missions with known launch dates before the AFSPC-44 launch in late 2020.
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