Third SLS dress rehearsal countdown scrubbed before completion
NASA engineers today scrubbed their third attempt to complete a dress rehearsal countdown of the agency’s giant SLS rocket when a leak was detected in a hydrogen fuel line.
The team will not conduct the terminal countdown activities today as planned and will assess next steps after today’s operations.
The problem appears to be “a leak … in the tail service mast umbilical.”
It is not clear yet how much of the countdown and fueling will be completed. Because of a faulty valve in the upper stage, NASA management had already decided to eliminate fueling of the rocket’s upper stage from the rehearsal. The problem today appears to involve the core first stage’s hydrogen tanks, which are presently partly filled only about 5%. Based on their last tweet, it appears they have not drained the tank, though they apparently will not continue the rehearsal today.
UPDATE: NASA just tweeted the following:
Teams have confirmed they have satisfied the test objectives for the ICPS [upper stage] LH2 [hydrogen tank] chilldown and after gathering additional data, will work to drain propellant from the rocket. They will inspect the TSMU umbilical connection, review data, and establish a go-forward plan.
This sounds as if the agency might decide they have completed enough of the dress rehearsal to consider it complete, and will now roll the rocket back to the vehicle assembly building for further check out.
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In 2020 when the world panicked over COVID I wrote that the panic was unnecessary, that the virus was apparently simply a variation of the flu, that masks were not simply pointless but if worn incorrectly were a health threat, that the lockdowns were a disaster and did nothing to stop the spread of COVID. Only in the past year have some of our so-called experts in the health field have begun to recognize these facts.
Your help allows me to do this kind of intelligent analysis. I take no advertising or sponsors, so my reporting isn't influenced by donations by established space or drug companies. Instead, I rely entirely on donations and subscriptions from my readers, which gives me the freedom to write what I think, unencumbered by outside influences.
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NASA engineers today scrubbed their third attempt to complete a dress rehearsal countdown of the agency’s giant SLS rocket when a leak was detected in a hydrogen fuel line.
The team will not conduct the terminal countdown activities today as planned and will assess next steps after today’s operations.
The problem appears to be “a leak … in the tail service mast umbilical.”
It is not clear yet how much of the countdown and fueling will be completed. Because of a faulty valve in the upper stage, NASA management had already decided to eliminate fueling of the rocket’s upper stage from the rehearsal. The problem today appears to involve the core first stage’s hydrogen tanks, which are presently partly filled only about 5%. Based on their last tweet, it appears they have not drained the tank, though they apparently will not continue the rehearsal today.
UPDATE: NASA just tweeted the following:
Teams have confirmed they have satisfied the test objectives for the ICPS [upper stage] LH2 [hydrogen tank] chilldown and after gathering additional data, will work to drain propellant from the rocket. They will inspect the TSMU umbilical connection, review data, and establish a go-forward plan.
This sounds as if the agency might decide they have completed enough of the dress rehearsal to consider it complete, and will now roll the rocket back to the vehicle assembly building for further check out.
Readers!
Please consider supporting my work here at Behind the Black. Your support allows me the freedom and ability to analyze objectively the ongoing renaissance in space, as well as the cultural changes -- for good or ill -- that are happening across America. Fourteen years ago I wrote that SLS and Orion were a bad ideas, a waste of money, would be years behind schedule, and better replaced by commercial private enterprise. Only now does it appear that Washington might finally recognize this reality.
In 2020 when the world panicked over COVID I wrote that the panic was unnecessary, that the virus was apparently simply a variation of the flu, that masks were not simply pointless but if worn incorrectly were a health threat, that the lockdowns were a disaster and did nothing to stop the spread of COVID. Only in the past year have some of our so-called experts in the health field have begun to recognize these facts.
Your help allows me to do this kind of intelligent analysis. I take no advertising or sponsors, so my reporting isn't influenced by donations by established space or drug companies. Instead, I rely entirely on donations and subscriptions from my readers, which gives me the freedom to write what I think, unencumbered by outside influences.
You can support me either by giving a one-time contribution or a regular subscription. There are four ways of doing so:
1. Zelle: This is the only internet method that charges no fees. All you have to do is use the Zelle link at your internet bank and give my name and email address (zimmerman at nasw dot org). What you donate is what I get.
2. Patreon: Go to my website there and pick one of five monthly subscription amounts, or by making a one-time donation.
3. A Paypal Donation or subscription:
4. Donate by check, payable to Robert Zimmerman and mailed to
Behind The Black
c/o Robert Zimmerman
P.O.Box 1262
Cortaro, AZ 85652
You can also support me by buying one of my books, as noted in the boxes interspersed throughout the webpage or shown in the menu above.
At the rate things are going, wouldn’t be surprised to see the rocket explode mid-maiden flight…
(Don’t wish for it, but wouldn’t be surprised. That is, if it’s ever launched at all!)
Close enough for Government work.
A cryo leak that manifests at cryo temperatures is a difficult problem. An LH2 leak is even worse due to the hazards. NASA is probably revisiting the events of the summer of 1990 when similar leaks appeared in multiple shuttles and Congress ended up grounding the fleet until the problem was solved. Few people know the root cause that was found. Anyone here know?