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Why is there is so much fuss about Falcon Heavy exploding on the way?

I don't understand why would they purposely design a rocket having a good chance of explosion during launch. If they are not confident in it, why are they launching?

Looks like a lot of risk and waste of time and money to me.

Who would even try to sit in such a rocket even in future when there is such a high chance of explosion? Do they have a plan to mitigate this risk?

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closed as primarily opinion-based by DylanSp, uhoh, Jan Doggen, ReactingToAngularVues, JCRM Feb 6 '18 at 23:11

Many good questions generate some degree of opinion based on expert experience, but answers to this question will tend to be almost entirely based on opinions, rather than facts, references, or specific expertise. If this question can be reworded to fit the rules in the help center, please edit the question.

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    $\begingroup$ A rocket using non explosive propellants would never leave the atmosphere. Hot water rockets have been used to accelerate cars for a crash test. But a bursting tank of very hot water is very dangerous too. These hot water rockets are useful for the very low speed of a car, but not for the extreamly high speed of an orbit. Without using highly energetic propellants, space exploration is impossible. $\endgroup$ – Uwe Feb 6 '18 at 16:37
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    $\begingroup$ I'm pretty sure ISRO has blown up a few rockets as well. It just goes with the territory. Building push-to-the-limit machines is different than writing C++, when it crashes and burns everybody knows about it! youtube.com/watch?v=2gnJTQ4E3yc Learning to make a rocket launch successfully is like learning to walk. Crash, burn, repeat. $\endgroup$ – uhoh Feb 6 '18 at 16:48
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    $\begingroup$ Because the press and social media like to speculate on it happening. Of course Space X is confident enough to launch. They want success too. $\endgroup$ – Jan Doggen Feb 6 '18 at 18:37
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    $\begingroup$ The OP would have really enjoyed the 60s! $\endgroup$ – Dennis Williamson Feb 6 '18 at 22:17
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The question misinterprets the comments of Elon Musk, who is trying to set expectations appropriately.

That is, this is a new vehicle, and there are issues that are next to impossible to model on the ground, nor test on the ground.

They have tested and planned for everything they can, but they accept there is complexity for which they cannot prepare.

So is this poorly designed? No, it is designed by some of the best rocket engineers in the world. (Demonstrably so — developed a new engine, Merlin, through 4 or 5 major iterations (1A → 1B → 1C → 1D → final build), developed a booster through multiple iterations (Falcon 9 Block 5 is due soon, from the 5 you can infer a number of previous iterations). Then they added on recoverability and reusability. Amazing stuff.

They have built a reusable capsule that has flown 14 times, and 2 have been reflown. Amazing stuff.

Yet, even so there is complexity that they cannot predict with complete confidence.

Now there is a different kind of confidence, not in practical things (have we covered all possible launch issues?) but economic confidence, where the actual performance of some physical things does not match with the economic reactions. (Ever see a company come in with higher earnings than expected and yet somehow tank its stock?)

Musk is trying to set expectations appropriately. This is a new booster. It is very complicated. They are as sure as they can be it will work. They are also sure there may be things they missed or could not test.

Thus this is really a test flight, and if it fails, they shall test again. If that fails, again shall they test until they succeed.

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    $\begingroup$ Yeah it seems strange but there are still things we can't accurately model and predict the behavior of. This is one of those cases. They've done everything they can to try to make sure everything will work but they won't know until they launch it. If it does blow up they'll analyze all their data and figure out what happened and how to prevent it. Then they'll repeat that until they are successful. My question at this point would be is it a limitation of not having enough information to build a model for the behavior or is it a limitation on processing power. $\endgroup$ – Evan Steinbrenner Feb 6 '18 at 18:11
  • $\begingroup$ Amazing stuff!! I always thought that if you want to succeed in something truly amazing, you should be prepared for some amazing failures along the way. Much respect to Elon and SpaceX for embracing that. $\endgroup$ – BruceWayne Feb 6 '18 at 19:01
  • $\begingroup$ "Ever see a company come in with higher earnings than expected and yet somehow tank its stock?" No. Can you share some examples? $\endgroup$ – TylerH Feb 6 '18 at 19:37
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    $\begingroup$ @TylerH Corning Inc. just a week ago. $\endgroup$ – mustaccio Feb 6 '18 at 19:55
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    $\begingroup$ @Geoffc More important than just testing again is that they will learn from this test, pass or fail, and make improvements based on that learning. $\endgroup$ – T.J.L. Feb 6 '18 at 21:56
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Musk himself talked about some of the challenges

“One of my biggest concerns is booster-to-booster interaction,” Musk explained. “You’ve got a lot of dynamics going on there. Those rockets are very flexible; if they flex in unexpected ways they could potentially impact one another.”

With three Falcon 9 cores, the acoustical noise generated by the launch is three times greater than a single Falcon 9 launch. SpaceX engineers think they understand these interactions, but they haven’t tested them in flight. Some unexpected resonancy could cause a structural failure. These systems have all been tested extensively on the ground, but ultimately, nothing compares to an actual flight test.

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Every orbital rocket launch comes with a risk of failure; modern, proven rockets are running about a 98%-99% success rate. I imagine that SpaceX is well over 90% confident in the success of this flight; the Falcon Heavy builds on the design of the Falcon 9 so there are fewer unknowns than there would be in an all new design.

By reminding people that this is a test flight, and there are unknowns, and it could fail, SpaceX both inoculates themselves against the failure case (because they can say "yeah, we told you so") and makes a successful flight look more exciting.

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