SpaceX’s workhorse Falcon 9 rocket conducted its Static Fire test on Tuesday, ahead of is its next launch from Vandenberg Air Force Base – set for the weekend. This launch will be the second reflight of a Block 5 Falcon 9 first stage, core B1048. The flight will also include the first west coast Return To Launch Site (RTLS) landing, which – so far – have only been performed at Landing Zones 1 and 2 at Cape Canaveral Air Force Station.
Launch was scheduled for No Earlier Than (NET) 7:22PM Pacific time (2:22 UTC) on October 6 (October 7 UTC) from SLC-4E at Vandenberg Air Force Base. However, the launch date has slipped 24 hours. It will be the first launch from SLC-4E since the Iridium NEXT 7 flight on July 25, 2018.
The static fire test is a full dress rehearsal of almost all the activities that will occur on launch day – from rollout of the stack to a short test firing of the 9 Merlin 1D engines on the launch pad.
The test is also a major milestone in launch preparations, as it ensures that all systems are working properly ahead of launch day.
Static fire test of Falcon 9 complete–targeting October 6 launch of SAOCOM 1A from Vandenberg Air Force Base in California.
— SpaceX (@SpaceX) October 2, 2018
SpaceX confirms a good test via a tweet that the company makes after a Quick Look review into the test results.
This rocket includes core 1048.2, the same Block 5 first stage that launched Iridium NEXT Flight 7 from the same launch pad. After helping push Iridium-7 to orbit, core 1048 landed on the Autonomous Spaceport Drone Ship (ASDS) Just Read the Instructions.
Core 1048 was brought back to the Port of Los Angeles to be unloaded from the ASDS and was later shipped back to SpaceX’s headquarters in Hawthorne, CA for inspections and refurbishment. After refurbishment, 1048 was sent back to SLC-4E to begin preparations for the SAOCOM-1A mission.
The payload for the launch is the 3000kg SAOCOM-1A satellite, being launched for CONAE – the Argentine space agency – to a Sun-Synchronous Orbit (SSO). SAOCOM-1A will be a part of a future six-satellite constellation in collaboration with the Italian COSMO-SkyMed constellation.
Together with the rest of the COSMO-SkyMed constellation, SAOCOM-1A will image Earth in high-resolution two times per day. It will use its L-band Synthetic Aperture Radar (SAR-L) to image the globe at up to 7m resolution in wide swaths, up to 400km wide.
SAOCOM-1A will be joined in 2019 by its twin, SAOCOM-1B. Like 1A, 1B will also be launched on a Falcon 9 from Vandenberg. 1B will also be launched alongside four secondary payloads, the SARE-1B 1-4 satellites, which will work alongside 1B.
The SAOCOM-1A launch will include the first RTLS landing at Vandenberg. Previously, all RTLS landings have occurred at Cape Canaveral Air Force Station, specifically at Landing Zones 1 and 2.
The Landing Zone at Vandenberg has been referred to as LZ-4 in the FCC filings made by SpaceX. LZ-4 likely stands for Landing Zone 4, although the name choice is interesting as there is currently no Landing Zone 3.
LZ-4 is situated next to SLC-4W, a former Atlas-Agena and Titan launch pad. SLC-4W was first used for an Atlas-Agena launch in 1963 and was later converted to support the Titan IIIB rocket. After the latter’s retirement, the pad was then used to launch the Titan 23G, before being deactivated in late 2003. In September 2014, unused structures at the pad from the Titan era were demolished to make way for future activities.
SpaceX signed a five-year lease in 2015 for SLC-4W, and began clearing land for its new landing pad soon after. Concrete was poured in sections to form the new landing zone, which was recently capped off with new paint – and apparently with the usual “X” – although not yet clear per satellite photos – at the center of the pad, similar to the designs of Landing Zones 1 and 2 and both of SpaceX’s Autonomous Spaceport Drone Ships.
LZ-4 is situated approximately 0.3km from SLC-4E, where SAOCOM-1A will launch from. This is much different than the setup at Cape Canaveral, where LZ-1 is over 9km from SLC-40.
The smaller distance will help to reduce the minimum time between launches, as it will take much less time to ship the landed first stage back to the Horizontal Integration Facility (HIF) to ready it for another launch.
After SAOCOM-1A, the next Falcon 9 launch will likely be either SSO-A or Es’hail-2, both scheduled for NET November from SLC-4E and LC-39A, respectively.