NASA's Space Launch System Just Came One Step Closer to Blast Off

After repeated delays, the Space Launch System, the workhorse for the ambitious Artemis Program, is now entering the final phase of testing before it is deployed for its first flight. NASA recently shared footage of the Umblicial Release and Retract Test (URRT) for this massive rocket that was conducted inside High Bay 3 at the Kennedy Space Center.  

NEW FOOTAGE ? Watch as the different platforms around the SLS rocket retract as part of the Umbilical Release and Retract Test (URRT) at @NASAKennedy. @NASAGroundSys conducted the test to prepare for future #Artemis I stacking and launch activities >> https://t.co/HNSKsaXf8c pic.twitter.com/IV8MrSwrYn

— NASA_SLS (@NASA_SLS) September 22, 2021

Umbilicals are tasked with supplying various components of a rocket launch such as power, fuel, coolant, and communications to the rocket at its launch pad. During the countdown leading up to the engine ignition of the rocket, the umbilicals are released in a pre-determined manner and retracted from their positions. The URRT tests the timing of the system.

Previous NASA rocket launches have used pyrotechnic separation systems. However, NASA has used different detachment mechanisms on the SLS such as winches and wire rope lanyards, and even multiple mechanisms for one umbilical, NASA Spaceflight reports.  

There are many umbilicals on the SLS, beginning with the Aft Skirt Electrical Umbilicals (ASEU) at the bottom along with the two Tail Service Mast Umbilicals (TSMU), which are responsible for fueling the rocket's core stage with liquid hydrogen and oxygen. The Core Stage Inter-Tank Umbilical (CSITU) is connected between the hydrogen and oxygen tanks at a height of 140 feet (42.7 m).

The Core Stage Forward Skirt Umbilical (CSFSU) sits at a height of 180 feet (54.9 m) between the first and second stages of the SLS, whereas the Interim Cryogenic Propulsion Stage Umbilical (ICPSU) is located at a height of 240 feet (73.2 m) and will be responsible for fueling the upper stage of the SLS along with providing electrical connections and pneumatics support. 

The tallest umbilical is the Orion Service Module Umbilical (OSMU) that supplies liquid coolant and purge air for the environmental control system and will also feature when crewed missions are taken up by the SLS. Apart from the ASEU, all other umbilicals were tested during the URRT, NASA Spaceflight reported. 

Following the successful test, the team will now move to Integrated Modal Testing (IMT) to determine the structural integrity and resonant frequency of the stacked rocket following which a Full Wet Dress Rehearsal is scheduled at Launch Complex 39B. While NASA has publicly declared that the Artemis I will be launched in 2021, it could likely be conducted in early 2022, the website said.