From Frank Howell@21:1/5 to All on Tue Apr 12 07:37:30 2022
NASA said in an April 9 blog post that it was delaying the wet dress
rehearsal (WDR) for the SLS by another three days. NASA previously
planned to restart the test with a “call to stations” for personnel
April 9, leading up to the tanking test and practice countdown April 11.
NASA said the call to stations is now set for April 12 and tanking on
April 14.
The latest delay is linked to a faulty helium check valve in the Interim Cryogenic Propulsion Stage (ICPS), the upper stage of the SLS. The valve prevents helium, used to purge propellant lines and drain propellant,
from escaping the rocket.
At this rate the SLS should fly about every other year and take the
exploration of Mars centuries instead of decades.