22.03.2022
Just a few days shy of five years since its first reflown Falcon 9 core took to the skies, SpaceX successfully launched a booster for the twelfth time in the opening minutes of Saturday morning. Delayed slightly by unfavorable weather, the B1051 core—which made its maiden voyage back in March 2019 to deliver an uncrewed Crew Dragon on the historic Demo-1 mission to the International Space Station (ISS)—roared into the night at 12:42 a.m. EST, laden with 53 Starlink low-orbiting internet communications satellites. It wrapped up what is expected to be SpaceX’s final flight of March, as the organization looks ahead to a busy April with two crewed ISS missions in record-breaking time.
All told, in her dozen missions B1051 has now lifted Demo-1, the Radarsat triplets, 522 Starlinks, multiple rideshare payloads and SiriusXM’s high-powered SXM-7 radio broadcasting satellite to orbit. In 2020, she became the first Falcon 9 to complete five missions in a single calendar year. And after playing catch-up with her many-times-flown sister B1049, from January 2021 B1051 has been the most-used Falcon 9 core, leading the fleet in logging eighth, ninth, tenth, eleventh and twelfth missions.
Last night’s launch also marked the eleventh Falcon 9 flight in 2022’s first eleven weeks. Eight boosters—including the brand-new B1071 core and a former Falcon Heavy side-booster, now reconfigured for “single-stick” operations—have staged nine missions from the Space Coast and two from Vandenberg.
They have lofted almost 400 Starlinks to orbit, although dozens were lost in early February following a severe geomagnetic storm. That has prompted SpaceX to implement an additional “burn” of the Falcon 9’s second stage and a longer coasting phase to ensure a higher initial circular orbit. The result is that Starlink “batches” are now deployed a little over an hour into flight, as opposed to 15 minutes after launch as was previously the case.
Last month, SpaceX founder Elon Musk indicated his intent to devote more capacity of these low-orbiting internet satellites to support Ukraine in its ongoing struggle against Russia’s aggression. “Starlink service is now active in Ukraine,” Mr. Musk tweeted on 26 February, shortly after Vladimir Putin’s troops invaded the country. “More terminals en-route.” Earlier in March, he added that Starlink remained “the only non-Russian communications system still working in some parts of Ukraine” but urged user caution, as the “probability of being targeted is high”.
Perhaps in a partial barbed response, the Falcon 9 fleet has been disparagingly nicknamed “American Broomstick” by several Russian political and space figures in recent weeks, as relations between Putin’s Kremlin and the West deteriorate to their lowest ebb in decades. But the SpaceX team came back with a prank of their own. “Time to let the American broomstick fly,” radioed the launch director over the countdown loop in the final seconds before a mission two weeks ago, “and hear the sounds of freedom.”
That freedom continued to resonate with last night’s picture-perfect flight. Last Monday, the Autonomous Spaceport Drone Ship (ASDS), “Just Read the Instructions”—ready for its second Falcon 9 “catch” after an extensive overhaul—put to sea out of Port Canaveral, bound for a recovery location about 390 miles (630 kilometers) downrange. And in the wee hours of Friday morning, the 230-foot-tall (70-meter) Falcon 9 booster was raised to the vertical on the Cape’s historic Space Launch Complex (SLC)-40.
Weather for Friday night’s launch was predicted to be 70-percent favorable, with a slight chance of showers and a risk of violating the Cumulus Cloud Rule. T-0 was delayed a little more than an hour, due to what SpaceX described as “unfavorable weather”, and B1051 commenced her record-setting twelfth mission at 12:42 a.m. EST Saturday. Eight minutes later, after pirouetting safely homeward, she alighted on the deck of JRTI to complete the eleventh drone-ship touchdown of her career; her Radarsat mission having seen a Return to Launch Site (RTLS) on solid ground at Vandenberg’s Landing Zone (LZ)-4.
Meanwhile, the Merlin 1D+ Vacuum engine powered the Starlink stack uphill in two “burns”, ahead of deployment at 62 minutes into the mission. Tweeting shortly afterwards, Mr. Musk noted that this was the heaviest payload ever lifted by a Falcon 9: at 16.25 metric tons, equivalent to 35,825 pounds (16,250 kilograms).
With the completion of Saturday’s mission, attention turns to a pair of Crew Dragon flights in the next few weeks. AxiomSpace, Inc.’s Ax-1—the first all-private crewed voyage to the ISS—was originally targeted to fly on 30 March, but has since slipped to no earlier than 3 April, as teams work to prepare Dragon Endeavour for her third launch.
In January 2021, former NASA astronaut, seasoned ISS commander and America’s most experienced spacewalker Mike Lopez-Alegria—now a senior executive for Houston, Texas-based AxiomSpace—was named to command Ax-1, his fifth space mission. Joining him for the historic ten-day flight would be entrepreneurs Larry Connor of the U.S., Mark Pathy of Canada and Israel’s Eytan Stibbe. The quartet reportedly entered quarantine after “months of training” last week and on Thursday wrapped up their Crew and Equipment Interface Test (CEIT), which AxiomSpace called a “test-drive” of Dragon Endeavour.
Assuming an on-time launch on 3 April, the Ax-1 crew will spend about eight days of their ten-day voyage aboard the ISS, supporting around 25 research investigations, before returning to an oceanic splashdown on 13 April. Previous plans then called for a “new” Crew Dragon vehicle (as-yet-unnamed) to fly on the 15th with NASA astronauts Kjell Lindgren, Bob “Farmer” Hines, together with Jessica Watkins and Italy’s Samantha Cristoforetti, for the Crew-4 mission.
They will embark on a stay of several months aboard the ISS. However, it was recently announced that Crew-4 will not spend a full, six-month increment on the station, but will return earlier, possibly in the August-September timeframe, to permit a “direct handover” when the Crew-5 mission arrives with U.S. astronauts Nicole Mann and Josh Cassada, Japan’s Koichi Wakata and perhaps—if the U.S./Russian ISS partnership does not suffer in the coming months—Russia’s Anna Kikina. The shortened increment means that plans for Cristoforetti to command the first part of Expedition 68 (numerically identified as “Expedition 68a”) will no longer take place.
As a result, when incumbent Expedition 66 Commander Anton Shkaplerov of Russia departs the ISS with fellow cosmonaut Pyotr Dubrov and NASA’s Mark Vande Hei on 30 March, he will hand the helm to U.S. astronaut Tom Marshburn. He will lead Expedition 67 alongside his Crew-3 crewmates Raja Chari, Kayla Barron and Germany’s Matthias Maurer, plus Russian cosmonauts Oleg Artemyev, Denis Matveev and Sergei Korsakov, who arrived at the station last week aboard Soyuz MS-21. Notably, the three cosmonauts floated aboard clad in yellow-and-blue flight suits, a none-too-subtle indication, perhaps, of their support for Ukraine in the ongoing strife.
NASA has recently announced that the Crew-4 launch has slipped to no earlier than 19 April, “to allow appropriate spacing for operations and post-flight data reviews between human spaceflight missions” and to permit “multiple consecutive launch attempts based on the orbital mechanics for arrival to the space station”.
Under this scenario, Lindgren, Hines, Watkins and Cristoforetti will arrive at the ISS on 20 April, whereupon Marshburn, Chari, Barron and Maurer will depart a few days later. Command of Expedition 67 will then pass to Artemyev, who will helm the station through his own return to Earth in late September. It is then anticipated that Japan’s Koichi Wakata, due to fly on Crew-5, will be the next ISS Commander, leading the first element of Expedition 68 following the arrival of Soyuz MS-22 in September.
If Crew-4 launches as planned on 19 April, less than a week after Ax-1’s return, it may set a record between the landing and launch of two U.S. crewed orbital missions. The current record elapsed between the return of shuttle Atlantis from STS-71 on 7 July 1995 and the launch of her sister ship Discovery on STS-70 just five days, 22 hours and 46 minutes later on the 13th. With Ax-1 set to return on 13 April and Crew-4 targeting launch on the 19th, the possibility of breaking the shuttle-era record remains high.
Quelle: AS