Update on Starship/Superheavy testing at Boca Chica
Link here.
While work appears to be proceeding aggressively, it increasingly looks like no orbital launch will occur before the end of this year. SpaceX engineers appear to be preparing two different Superheavy prototypes, #7 and #9, but both are still undergoing modifications based on recent engine tests. In addition, modifications to Starship prototype #24 continue.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
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The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
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Link here.
While work appears to be proceeding aggressively, it increasingly looks like no orbital launch will occur before the end of this year. SpaceX engineers appear to be preparing two different Superheavy prototypes, #7 and #9, but both are still undergoing modifications based on recent engine tests. In addition, modifications to Starship prototype #24 continue.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
“… test the autogenous pressurization system. …”
This is an advancement, correct? Meaning the booster and starship will not have to consume scarce helium? ( But then, is helium scarce in the world? I do worry every time I see helium balloons in my local supermarket. )
The problems with the concrete of the launch pad shattering into pieces … is that occurring because the booster is held in place during the static fire? Normally the booster clears the launch pad before doing this level of damage to the concrete?
Is SpaceX being ultra cautious out of concern that a launch explosion will result in the FAA locking them down for an extended period of time? Would an actual super heavy launch with a subset of its raptor engines meet the same testing requirements of these static fire tests, with the added advantage of SpaceX being able to also test how they can get super heavy to land safely back on Earth.
Stephen Richter asked: “[the autogenous pressurization system] is an advancement, correct? Meaning the booster and starship will not have to consume scarce helium? ( But then, is helium scarce in the world? I do worry every time I see helium balloons in my local supermarket. )”
From the linked article:
Although there is some scarcity of helium on Earth, there is no known supply on the Moon or on Mars, two targets for Starship. If the Starship design can avoid using helium, then it has a much better capability of using onsite resources (in-situ resource utilization) without the need to bring supplies from home. Since Starship can — or will — use the propellants as pressurants, then why not do the same for Super Heavy? It should also make the ground support hardware less complicated.
There are problems to overcome, however, because this has not really been done before, so Stephen is correct, it is an advancement. Helium can be stored onboard at high pressure and released into the propellant tanks without fear that it will condense, but the same is not so true when using the propellants themselves. I suspect that SpaceX had that problem with one of the Starship landing tests, last year. When a gas (e.g. helium, oxygen, methane) goes from a high-pressure tank into a lower-pressure tank the reduction in pressure cools the gas, and there is a risk that the gas condenses into liquid form and does not increase the pressure in the target tank as it is supposed to do.
Another concern that I have is that the propellants may be chilled to near the freezing point, so any gaseous propellant could be chilled by the liquid propellant and condense, decreasing rather than increasing the tank pressure.
SpaceX has probably been spending the past two to six years trying to figure out how to do this successfully. I would not be surprised if they keep this as a proprietary trade secret.