NASA’s massive SLS Mobile Launcher riding atop crawler-transproter-2 drives along the crawlerway to Launch Complex 39B at NASA’s Kennedy Space Center in Florida on Jun. 27, 2019 for the final trip with no rocket atop time for key final testing and checkouts. Its next roll to the pad will be with the 1st Space Launch System rocket and integrated Orion spacecraft in preparation for the debut launch of Artemis 1 slated for NET late 2020 as part of NASA’s Explore Moon to Mars initiative. Credit: Ken Kremer/kenkremer.com/spaceupclose.com

Orion will return to Earth and splashdown in the
Pacific Ocean off the coast of California, where it will be retrieved and
returned to Kennedy.


Here are further ML details from NASA:


With the mobile launcher now at the pad, some of
the final testing that will take place includes water flow testing of the ignition
overpressure and sound suppression systems that will help protect
the SLS, Orion, the mobile launcher and launch pad from the extreme
acoustic and temperature environment of launch. Testing also will evaluate
cryogenic flows for the ultra-cold propellant and additional checkout of electrical
and umbilical systems.


“One important test coming up involves swinging
three umbilical arms on the mobile launcher simultaneously, which is the first
time all three arms will move together, just as they would during launch,” said
Cliff Lanham, NASA’s senior project manager for the mobile launcher at Kennedy.


The three arms being tested are the core stage
intertank umbilical, the core stage forward skirt umbilical and the interim
cryogenic propulsion stage (ICPS) umbilical. The umbilicals for the intertank
and forward skirt will provide power and air to purge the lines for the SLS
rocket. The umbilical for the ICPS will provide cryogenic propellants – or
super-cooled liquid hydrogen and liquid oxygen – in addition to power and purge
air to the ICPS,
which provides the power and propulsion needed to send Orion to the Moon and
back.


“The arms, built offsite, were first sent to the
Launch Equipment Test Facility where each one was tested individually before
installation on the mobile launcher,” said Florez. “Now it’s time for the
integrated test to validate that all three arms can retract at the same time so
that when the countdown clock hits zero, each arm swings away at the right time
for that historic launch moment.”


After final testing at the pad is complete,
which is slated for the end of September, the mobile launcher will roll back to
the VAB for minor testing before SLS and Orion stacking.


“Once the vehicle is stacked on the mobile
launcher, it will roll to the pad one final time for a rehearsal prior to
launch,” said Lanham. “It’s exciting to see it all falling into place.”


Ken will be onsite at the Kennedy Space Center
for live coverage of NASA’s Orion Ascent Abort-2 test launch. 


Watch for Ken’s continuing
onsite coverage of NASA, SpaceX, ULA, Boeing, Lockheed Martin, Northrop Grumman
and more space and mission reports direct from the Kennedy Space Center, Cape
Canaveral Air Force Station, Florida and Wallops Flight Facility, Virginia.