SLS launch scrubbed

An issue in one of the refurbished shuttle main engines that are used in SLS’s core stage caused the launch today to be scrubbed.

The launch director halted today’s Artemis I launch attempt at approximately 8:34 a.m. EDT. The Space Launch System rocket and Orion spacecraft remain in a safe and stable configuration. Launch controllers were continuing to evaluate why a bleed test to get the RS-25 engines on the bottom of the core stage to the proper temperature range for liftoff was not successful, and ran out of time in the two-hour launch window. Engineers are continuing to gather additional data.

More information here and here. From the second link:

The four RS-25 engines on Artemis I are ones that were still in service at the end of the Shuttle program. But, for Artemis I, at least one component on each of the Core Stage engines comes from the three engines that powered Columbia to orbit on STS-1 on April 12, 1981. “It might be a valve, it might be a bolt, for others, it’s pieces of wiring, little things like that,” said Aerojet Rocketdyne’s Bill Muddle, RS-25 lead field integration engineer, in an interview with NASASpaceflight. “But there is something from the STS-1 engines on each of these [for Artemis I].”

Originally NASA had wanted to do this same bleed test during one of the two wet dress rehearsal countdowns prior to today’s launch attempt, but other issues with the rocket during those rehearsals made it impossible. As a result, the agency discovered this issue during the launch countdown.

Nor was this engine problem the only issue during this morning’s countdown.
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How SLS reveals the difference between state-run propaganda and real journalism

The cost of SLS

On August 29, 2022, NASA will attempt the first launch of a government-built, government-owned, and government-designed rocket in more than a decade. The rocket’s development took more than eighteen years, moved in fits and starts due to political interference and mandates, cost more than $50 billion, and has been both behind schedule and overbudget almost from day one. Along the way NASA management screwed up the construction of one multi-million dollar test stand, built another it will never use, mismanaged that test program, dropped a rocket oxygen tank, and found structural cracks in an early Orion capsule.

This dubious achievement, even if the launch and month-plus-long mission of the Orion capsule to lunar orbit and back is a complete success, is hardly something to tout. NASA claims it and this rocket will make it possible for America to explore the solar system, but any honest appraisal of SLS’s cost and cumbersome design immediately reveals that claim to be absurd. SLS can launch at best once per year, and in truth will likely lift off at a much slower rate. It will also eat up resources in the American aerospace industry from technology better designed, more efficient, and more capable of doing the job.

Worse, the generally sloppy management of this program, with numerous major errors in design and construction, raises serious questions about the safety of any future manned flight.

And yet, as this launch day approaches, the American established press is going ga-ga over SLS. Below are just a small sampling:
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Engineers replace engine controller on SLS core; launch to be delayed

Engineers have successfully replaced the failed engine controller on the core stage of NASA’s SLS rocket.

Last week engineers and technicians successfully removed and replaced an engine controller from one of four RS-25 engines after the team identified an issue during a power-up test of the rocket’s core stage. Engineers are now performing standard engine controller diagnostic tests and check-outs, including controller power-up and flight software load. Subsequently, the team will work to complete all remaining SLS pre-flight diagnostic tests and hardware closeouts in advance of a mid-February rollout for a wet dress rehearsal in late February. NASA will set a target launch date after a successful wet dress rehearsal test.

The official schedule still lists the launch for February, but NASA has already admitted this is now impossible. Once they complete the wet dress rehearsal on the launchpad they will have to roll the rocket back into the Vehicle Assembly Building to do further tests. While it remains possible for NASA to meet an April launch window, more likely the agency will push back to windows during the summer.

Thus, the race between SLS and Starship for completing the first orbital flight remains neck-and-neck. Starship could launch this spring, but it faces an uncertain schedule determined not by SpaceX but by the bureaucracy in the federal government, which is reviewing the FAA’s environment reassessment for the Boca Chica launch site and really has no requirement to meet any schedule at all. The FAA says it plans to approve the reassessment by the end of February, but that is simply made up deadline. It could revise it at will at any time.

NASA meanwhile is still pushing to launch SLS in April, but this launch date is entirely unrealistic. Expect NASA to announce a new target date sometime in the summer in the coming weeks.

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