SpaceX is targeting their Starlink v1.0 L18 flight, or 19th Starlink mission, for launch from SLC-40 at the Cape Canaveral Space Force Station on Thursday, 4 February at 01:19 EST (06:19 UTC).
This is scheduled to be followed by a second Starlink mission from nearby LC-39A just under 28 hours later, keeping SpaceX on track to achieve their planned 48 launches this year while the Eastern Range and 45th Space Wing of the United States Space Force remain on target to reach their own goal of supporting at least 48 launches a year — or one per week — from Florida.
Pending an on-time liftoff or even a 24 hour delay, the Starlink v1.0 L18 flight (“L18”) will be the first Starlink mission to launch out of numerical sequence as its liftoff is scheduled for just more than one day before the Starlink v1.0 L17 (“L17”) flight.
This kind of out-of-sequence launch — while incredibly common through the Space Shuttle program — is one of the first highly public instances in more than a decade with U.S. missions of flights ending up out of numerical sequence because of delays.
Specifically, this occurrence with Starlink L18 is caused by the L17 mission’s continued troubles both pre- and post-static fire. The L17 mission was originally scheduled for 27 January and is now targeting Friday, 5 February.
After lifting off from SLC-40, Falcon 9 will pitch and roll onto the proper heading to achieve a 53 degree inclination orbit.
After stage separation, first stage booster B1060-5 will head for a landing on the Of Course I Still Love You drone ship positioned approximately 630 km northeast of the launch site in the Atlantic Ocean off the coast of Charleston, South Carolina.
|B1060 missions||Launch date||Turnaround time|
|GPS III SV03||30 June 2020||N/A|
|Starlink L11||3 September 2020||65 days|
|Starlink L14||24 October 2020||51 days|
|Türksat-5A||8 January 2020||76 days|
|Starlink L18||4 February 2021||27 days|
At just 27 days from its last mission, booster B1060-5 will set the new fleet-leader and world record for fastest turnaround time of the same rocket between missions. The previous record was 38 days, held by Falcon 9 booster B1051.
Likewise, the two payload fairing halves will parachute into the Atlantic approximately 730 km northeast of the launch site for recovery by the ships GO Ms. Tree and GO Ms. Chief. One half of the fairing was previously used on the GPS III SV-03 mission while the other half was previously used on the SAOCOM 1B flight.
Given the proximity of the two drone ships for the two identical Starlink missions, it is likely that cameras on Just Read The Instructions will see B1060-5 making its landing on Of Course I Still Love You.
The two Starlink missions, if they hold, would launch 27 hours 55 minutes apart from each other — breaking the current post-Range upgrade record of just under 35 hours set in August 2019.
Even quicker launch-to-launch cadence was common in the 1960s — including with human Gemini flights, some of which launched from a neighboring pad just 90 minutes after their uncrewed target vehicle had lifted off.
The rapid cadence capability was mainly due to the Eastern Test Range’s use as a defense station against potential enemy attack against the United States during the Cold War — a scenario that would have required a rapid salvo of launches.
With détente in the mid-1970s, this rapid launch capability was gradually discontinued.
However, the quick rise of the commercial rocket sector and proliferation of new companies and launchers prompted the 45th Space Wing to foresee the need to re-introduce such rapid launch support capability in the mid-2010s.
The new series of upgrades and improvements were designed to account for the anticipated launch demand from SpaceX and emerging commercial companies as well as use of the Range by United Launch Alliance.
This initiative involved a multi-year process of upgrading equipment and facilities and increasing staffing to appropriate levels to ensure different teams could be ready to take over between launches.
Likewise, the mid-2010s plan called for the Range to be able to reconfigure between two completely different rockets (i.e., a Falcon 9 and an Atlas V) in 36 hours while 16 hours would be required between two Falcon 9s launching from different pads.
The Range and the 45th have since met and exceeded those stated goals, accomplishing a Falcon 9 and Atlas V launch with just under 35 hours of separation between them in August 2019.
Speaking to that milestone at the time, Col. Mark Shoemaker, then-Commander of the 45th Operations Group, said: “One a week is the average we’re aiming for. Obviously, we might have situations … where we do two in 35 hours and then maybe the next week … we have none.”
Since then, the Range has supported similar 34-36 hour planned and approved turnarounds between Atlas Vs and Falcon 9s — though the involved missions have then slipped or scrubbed, negating the dual launch scenarios from becoming reality.
However, in some cases, the back-to-back launches approved by the Range have showcased deeper improvements to cut turnaround times even more since 2019.
In August 2020, the Range approved less than 24 hours of turnaround time between a United Launch Alliance Delta IV Heavy and a SpaceX Falcon 9. Further, two Falcon 9 missions were — at one point in 2020 — both scheduled within 16 hours of each other.
This week, the Range approved a 4 hour 17 minute separation between the Starlink L18 and L17 missions, though they confusingly only did so after SpaceX had requested to move the L17 flight to Friday, 5 February.
Nevertheless, it proved the Range can support two Falcon 9 missions just four hours apart.
Two launches this week would keep the 45th Space Wing on track to support up to 48 missions this year, including the more than 40 missions from SpaceX and the myriad of flights from United Launch Alliance, including the potential end-of-year introduction of their new Vulcan rocket as well as eight manifested flights of the Atlas V.
Two of those Atlas V flights include Starliner’s uncrewed Orbital Flight Test 2 (OFT-2) as well as a three-person Crewed Flight Test (CFT) scheduled sometime later in the year.
According to the most-recent schedules, it also remains possible that the Terran-1 rocket from Relativity Space as well as the New Glenn from Blue Origin could debut this year as well from the Cape.
Whether or not SLS could join as well will largely be determined following completion of the second hot fire test at the Stennis Space Center in Mississippi. That retest does not have a confirmed test date at this time, with NASA noting “the week in Feb. 21” as the earliest possible timing.
“While a historic journey awaits us in space, I hope this mission reinforces how far inspiration can take us and the extraordinary achievements it leads to here on Earth.” – Jared Isaacman, Inspiration4 Commander pic.twitter.com/y41tsFJzNu
— Inspiration4 (@inspiration4x) February 1, 2021
As with the 45th Space Wing’s goal of supporting 48 missions a year from Florida, launching both Starlink flights this week would likewise keep SpaceX on track for a record 48 launches of their own in 2021 — though not all will be flown from Florida.
Notably, NASA’s Double Asteroid Redirect Test (DART) mission is slated to launch no earlier than 22 July 2021 from Vandenberg Air Force Base, California.
However, the vast majority of SpaceX’s 2021 manifest is from Florida, with one such flight officially added Monday in the form of the Inspiration4 mission which will be the first completely private human spaceflight in history.
SpaceX has also manifested two crew rotation missions to the International Space Station for NASA in Crew-2 and Crew-3 as well as the first private mission to the Station from Axiom.
Crew-2 and Crew-3 are currently targeting 20 April and “September/October”, respectively, while Inspiration4 is set for no earlier than October followed by Axiom Space-1 in December.
To meet its planned number of launches this year, SpaceX needs to achieve an average launch cadence of one per week, something a doubleheader Starlink event this week would do by bringing the company’s completed manifest for the year to five flights in just five weeks.
Lead image credit: SpaceX
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