On the first anniversary since her maiden launch—and after a 24-hour delay due to a last-second Range violation—one of SpaceX’s most seasoned Falcon 9 boosters took flight for the eighth time Wednesday to deliver 88 discrete nanosatellites, CubeSats, a hosted payload and two SHERPA tugs into a 340-mile-high (550 km) Sun-Synchronous Orbit (SSO) on the Transporter-2 rideshare mission.
And just eight minutes later, for the first time in her career, B1060 returned to touch down at Landing Zone (LZ)-1, safe and sound back at the Cape. It was the first “land” landing of any Falcon 9 core stage so far in 2021.
Primary objective was Transporter-2, SpaceX’s second dedicated “rideshare” mission, coming only a few months since January’s record-breaking 143-satellite Transporter-1, which remains the largest number of discrete payloads ever lofted to orbit aboard a U.S. launch vehicle.
Originally scheduled to fly last Friday, SpaceX elected to stand down for a few additional days, citing a need for “additional time for pre-launch checkouts”, before announcing that it was tracking a new T-0 on Tuesday afternoon.
At the same time, it revealed that although Transporter-2 would comprise a still-pretty-respectable 88 payloads, it would actually feature “more customer mass” than Transporter-1 did.
And whereas SHERPA-FX can support multiple payload deployments and effect independent telemetry services, SHERPA-LTE benefits from xenon-fed electric propulsion and can deliver spacecraft to geostationary, cislunar or Earth-escape orbits.
Designated SpaceX Rideshare (SXRS)-5, Spaceflight, Inc.’s customer haul included six microsatellites, 29 CubeSats and a single “hosted” payload.
Additionally, dozens more small satellites headed uphill on Transporter-2, representing no fewer than 20 sovereign countries, from Argentina to the United Kingdom, from Finland to the United Arab Emirates and from the Netherlands to Thailand.
Of those customers, topping the list was Spaceflight, Inc., which flew no less than 36 payloads via its SHERPA-FX satellite dispenser—embarking on its second mission, following an inaugural outing on Transporter-1—and the SHERPA-LTE tug, on its first flight.
Launches into polar orbit are expected to commence later this summer from Vandenberg Space Force Base, Calif., with the Autonomous Spaceport Drone Ship (ASDS) “Of Course I Still Love You” having passed through the Panama Canal last week as it makes its long voyage from the East Coast to its new home on the West Coast.
Blackened and scorched from seven prior launches and high-energy re-entries, B1060 was trundled out to SLC-40 and elevated to the vertical last week, before her nine Merlin 1D+ first-stage engines underwent a customary Static Fire Test.
Tuesday’s countdown proceeded normally, with the Eastern Range declaring itself “Green”, but the clock abruptly stopped at T-11 seconds with an ominous “Hold, Hold, Hold” call over the net, due to the Range having declared a “No-Go” condition.
Despite an expansive “launch window”, lasting almost an hour, the attempt was scrubbed. The finger of blame was eventually pointed at a wayward helicopter which had entered the launch danger area.
So it was that B1060 wound up flying the eighth mission of her career on the one-year anniversary of her first flight. Weather conditions for Wednesday were projected at about 70-percent-favorable, sliding to 60 percent in the event of another postponement to Thursday.
“A convergent band is moving over the Spaceport with abundant shower activity,” noted the 45th Weather Squadron at Patrick Space Force Base. “After this moves through, a more typical easterly flow scenario should persist with isolated morning coastal showers.”
Potential showstoppers for Wednesday included a possible violation of the Cumulus and Anvil Cloud Rules associated with inland thunderstorm activity.
And those potential showstoppers did not take long to show up. With a 58-minute “launch window” extending from 2:56 p.m. EDT through 3:54 p.m. EDT, SpaceX elected firstly to move T-0 to 3:11 p.m. EDT, then 3:31 p.m. EDT, on account of the weather situation.
Wednesday’s launch also marked the first time that B1060 had ever returned to a solid-ground touchdown at the LZ-1 landing pad. All previous times, she alighted on the deck of the Autonomous Spaceport Drone Ship (ASDS), situated offshore in the Atlantic Ocean.
Following a nominal ascent, the Merlin 1D+ Vacuum engine of the Falcon 9’s first stage shut down about 8.5 minutes into today’s flight. The stack then coasted for about 45 minutes, before the engine re-lit for a few seconds, ahead of payload deployment.
Beginning with NASA’s PACE-1 technology demonstration satellite at 58 minutes after launch and ending with the deployment of Spaceflight, Inc.’s SHERPA-FX2 and SHERPA-LTE1 at 81 minutes, the process was bookended at 87 minutes with the release of the three Starlinks.
Today’s landing marked the 22nd time a Falcon 9 core had returned to land on solid ground, out of 23 attempts, when one also considers the December 2018 loss of a booster following a stalled grid-fin hydraulic pump which forced it to ditch out to sea in the Atlantic.
Three Falcon 9 cores returned to land safely on Landing Zone (LZ)-4 at Vandenberg Space Force Base, Calif., between October 2018 and last November’s Sentinel-6A Michael Freilich ocean-monitoring mission, whilst 19 others—including the dual returning side-boosters of all three Falcon Heavies—have done so at the Cape.
Launching and returning from her latest mission makes B1060 only the fourth Falcon 9 to log as many as eight flights. She first flew last 30 June, lifting the third Block III GPS satellite towards Medium Earth Orbit.
Nine weeks later, she launched a second time—cementing a record for the shortest interval between two Falcon 9 flights from the Space Coast—and went on to fly a third mission on 24 October. Both were laden with 60-strong batches of Starlinks. As a side note, her third flight marked the 100th successful launch of a Falcon-class booster.
But B1060’s real record-setting credentials have been concentrated into the first half of 2021. She flew SpaceX’s first mission of the year on 7 January with Turkey’s powerful Türksat 5A geostationary communications satellite, then was turned around in only 27 days to fly a Starlink payload uphill on 4 February, in what SpaceX touted as “rapid reusability”.
This neatly eclipsed the Falcon 9’s previous launch-to-launch turnaround record for a single booster of only 38 days, set a few weeks earlier and still stands to this day.
More recently, in late March and late April she lifted another pair of 60-strong Starlink batches to orbit. And on her most recent mission, she became the first Falcon 9 core to launch four times in four consecutive months.