<story><title>SpaceX Starship rocket explodes minutes after launch from Texas</title><url>https://apnews.com/article/spacex-starship-launch-elon-musk-d9989401e2e07cdfc9753f352e44f6e2</url></story><parent_chain><item><author>sbuttgereit</author><text>I agree with this assessment and probably the biggest problem in the test.  After that, they still have a fair way to go on Raptor reliability; I was a bit disappointed with the number of engine outs: clearly the engines have not arrived.  I think the big win of the day was the overall resilience of the vehicle.  It seemed to handle (what looked to be) possibly explosive engine failures and kept going and stayed intact... even through the tumbling.&lt;p&gt;I think this is a case where the engineers can look at the numbers and calculate for a limited variety of well defined (and foreseen) scenarios, but that they continue to fail to have an intuitive sense of the power of the thing that they built.  Given the complexity of the real world, they can &amp;quot;engineer&amp;quot; themselves into an undue sense of certainty about what will happen when they light a rocket of this power... and I think we see the result of that.  As an aside, this is precisely where I think we&amp;#x27;ll some of the biggest failings for LLM based AI... it can get you some nice words to describe a situation and may be able to do all the calculations... but having that gut feeling that maybe there&amp;#x27;s more to a situation than the numbers would have you believe is still something that humans can do better (though not SpaceX this time around).&lt;p&gt;In closing, if I had a binary choice of &amp;quot;successful&amp;quot; or &amp;quot;unsuccessful&amp;quot; for this test... I&amp;#x27;d still probably call it successful.  But only just; it&amp;#x27;s a very qualified success given some of the test parameters SpaceX had set for themselves.&lt;p&gt;(of course we could find out about even more damage to &amp;quot;stage 0&amp;quot; which might shift my assessment... but we know that they&amp;#x27;re in the process of putting in a deluge system at least already, so I&amp;#x27;m being a bit more charitable regarding expectations than I might otherwise be.)</text></item><item><author>samwillis</author><text>Exactly, the two untested things were stage zero (all the new ground infrastructure) and stage one (booster).&lt;p&gt;I think it&amp;#x27;s clear one of their biggest lessons is that the construction of the launch mount is wrong, and it REALY needs a flame diverter. Take a look at this photo: &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;mobile.twitter.com&amp;#x2F;LabPadre&amp;#x2F;status&amp;#x2F;1649062784167030785&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;mobile.twitter.com&amp;#x2F;LabPadre&amp;#x2F;status&amp;#x2F;16490627841670307...&lt;/a&gt;&lt;p&gt;That massive hole in the ground should not have happed, and I suspect that was not an expected possibility. It is a very costly mishap and could mean completely rebuilding the launch mount. With the excavation and rebuild, that could be months or even as long as a year.&lt;p&gt;On top of that there was significantly more debris making its way to South Padre, the political fallout (pun intended) will be significant, and could cause issues with launch licenses going forward.</text></item><item><author>kortex</author><text>Initially posted this as a reply, but going top-level, cause the hot takes are too spicy for my liking.&lt;p&gt;So the plan was to test x, y, and z. Launch sequence and takeoff, stage separation and Starship engine light, and the post-launch stuff like booster wet landing, reentry, and heat tiles. The booster by itself is not aerodynamic, so the only way to test x is with a starship on top. And if you have starship, you might as well test y and z. But it&amp;#x27;s not a primary goal. Any more effort in polishing y and z is &amp;quot;premature optimization&amp;quot;. X was the test. SpaceX did the X, we got max Q.&lt;p&gt;On the most recent SmarterEveryDay video on encasing a Prince Rupert&amp;#x27;s drop in glass, sculptor Cal Breed talks about the moment when a process fails. He could stop there and restart, saving some time, but instead all the pressure is off, and he &amp;quot;makes as many mistakes as possible&amp;quot; for the rest of the build.
Quote is towards the end, but the whole vid is worth a watch.&lt;p&gt;&lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;youtu.be&amp;#x2F;C1KT8PS6Zs4&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;youtu.be&amp;#x2F;C1KT8PS6Zs4&lt;/a&gt;&lt;p&gt;&lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.calbreed.com&amp;#x2F;&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.calbreed.com&amp;#x2F;&lt;/a&gt;&lt;p&gt;Edit: also, they &lt;i&gt;needed&lt;/i&gt; the flight plan all the way through &amp;quot;total success&amp;quot; in order to file with the FAA. You can&amp;#x27;t just have &amp;quot;oh sweet, 100% of booster things worked, we now have a suborbital craft careening on a parabolic trajectory&amp;quot;. I didn&amp;#x27;t read a flight plan, but I imagine they must have spelled out each possible outcome exhaustively.</text></item></parent_chain><comment><author>samwillis</author><text>&amp;gt; After that, they still have a fair way to go on Raptor reliability&lt;p&gt;I suspect the debris from blowing a whole in the ground was the biggest contributing factor for the engines out. It looked like at lease 4 we&amp;#x27;re gone before it left the pad.</text></comment>
<story><title>SpaceX Starship rocket explodes minutes after launch from Texas</title><url>https://apnews.com/article/spacex-starship-launch-elon-musk-d9989401e2e07cdfc9753f352e44f6e2</url></story><parent_chain><item><author>sbuttgereit</author><text>I agree with this assessment and probably the biggest problem in the test.  After that, they still have a fair way to go on Raptor reliability; I was a bit disappointed with the number of engine outs: clearly the engines have not arrived.  I think the big win of the day was the overall resilience of the vehicle.  It seemed to handle (what looked to be) possibly explosive engine failures and kept going and stayed intact... even through the tumbling.&lt;p&gt;I think this is a case where the engineers can look at the numbers and calculate for a limited variety of well defined (and foreseen) scenarios, but that they continue to fail to have an intuitive sense of the power of the thing that they built.  Given the complexity of the real world, they can &amp;quot;engineer&amp;quot; themselves into an undue sense of certainty about what will happen when they light a rocket of this power... and I think we see the result of that.  As an aside, this is precisely where I think we&amp;#x27;ll some of the biggest failings for LLM based AI... it can get you some nice words to describe a situation and may be able to do all the calculations... but having that gut feeling that maybe there&amp;#x27;s more to a situation than the numbers would have you believe is still something that humans can do better (though not SpaceX this time around).&lt;p&gt;In closing, if I had a binary choice of &amp;quot;successful&amp;quot; or &amp;quot;unsuccessful&amp;quot; for this test... I&amp;#x27;d still probably call it successful.  But only just; it&amp;#x27;s a very qualified success given some of the test parameters SpaceX had set for themselves.&lt;p&gt;(of course we could find out about even more damage to &amp;quot;stage 0&amp;quot; which might shift my assessment... but we know that they&amp;#x27;re in the process of putting in a deluge system at least already, so I&amp;#x27;m being a bit more charitable regarding expectations than I might otherwise be.)</text></item><item><author>samwillis</author><text>Exactly, the two untested things were stage zero (all the new ground infrastructure) and stage one (booster).&lt;p&gt;I think it&amp;#x27;s clear one of their biggest lessons is that the construction of the launch mount is wrong, and it REALY needs a flame diverter. Take a look at this photo: &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;mobile.twitter.com&amp;#x2F;LabPadre&amp;#x2F;status&amp;#x2F;1649062784167030785&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;mobile.twitter.com&amp;#x2F;LabPadre&amp;#x2F;status&amp;#x2F;16490627841670307...&lt;/a&gt;&lt;p&gt;That massive hole in the ground should not have happed, and I suspect that was not an expected possibility. It is a very costly mishap and could mean completely rebuilding the launch mount. With the excavation and rebuild, that could be months or even as long as a year.&lt;p&gt;On top of that there was significantly more debris making its way to South Padre, the political fallout (pun intended) will be significant, and could cause issues with launch licenses going forward.</text></item><item><author>kortex</author><text>Initially posted this as a reply, but going top-level, cause the hot takes are too spicy for my liking.&lt;p&gt;So the plan was to test x, y, and z. Launch sequence and takeoff, stage separation and Starship engine light, and the post-launch stuff like booster wet landing, reentry, and heat tiles. The booster by itself is not aerodynamic, so the only way to test x is with a starship on top. And if you have starship, you might as well test y and z. But it&amp;#x27;s not a primary goal. Any more effort in polishing y and z is &amp;quot;premature optimization&amp;quot;. X was the test. SpaceX did the X, we got max Q.&lt;p&gt;On the most recent SmarterEveryDay video on encasing a Prince Rupert&amp;#x27;s drop in glass, sculptor Cal Breed talks about the moment when a process fails. He could stop there and restart, saving some time, but instead all the pressure is off, and he &amp;quot;makes as many mistakes as possible&amp;quot; for the rest of the build.
Quote is towards the end, but the whole vid is worth a watch.&lt;p&gt;&lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;youtu.be&amp;#x2F;C1KT8PS6Zs4&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;youtu.be&amp;#x2F;C1KT8PS6Zs4&lt;/a&gt;&lt;p&gt;&lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.calbreed.com&amp;#x2F;&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.calbreed.com&amp;#x2F;&lt;/a&gt;&lt;p&gt;Edit: also, they &lt;i&gt;needed&lt;/i&gt; the flight plan all the way through &amp;quot;total success&amp;quot; in order to file with the FAA. You can&amp;#x27;t just have &amp;quot;oh sweet, 100% of booster things worked, we now have a suborbital craft careening on a parabolic trajectory&amp;quot;. I didn&amp;#x27;t read a flight plan, but I imagine they must have spelled out each possible outcome exhaustively.</text></item></parent_chain><comment><author>jackmott42</author><text>&amp;gt; but having that gut feeling that maybe there&amp;#x27;s more to a situation than the numbers would have you believe is still something that humans can do better&lt;p&gt;In my life experience so far, humans having gut feelings it 99% of the time complete nonsense. But people forget the 99 times and that one time their gut was right they tell that story forever about how smart they were.</text></comment>