Thread by @elteslaengineer

The following 🧵is about the @SpaceXStarship massive crater and a preliminary RCA with my Dad who is a Civil Engineer, specializing in structural steel structures. This is the picture we stared at for 30 mins.

1. "The failed mission that could have been successful" - I have seen many videos and I am amazed regarding the amount of concrete elements that went flying during launch.

2. Design flaws on the launch pad platform are evident. Looks like a concrete beams were covered by fire resistant steel plates and maybe the concrete was fire rated. But clearly a design flaw.

3. Picture of a chunk of concrete that made its way a significant distance from the launch pad. If you look closely looks like temperature, dynamic and acoustic loads spalliated the concrete.

4. Spalling: The Effect High Heat Has on Concrete. This are similar to the pieces of concrete balls seen project out from the launch pad.

5. When concrete is exposed to temperatures +212° F (boiling point of H2O), the moisture turns to steam. If the temperature rises faster than the steam can escape through the concrete matrix, the rising pressures exceed the strength of the concrete and it begins to break apart.

6. What has @NASA done with their designs? Trench and flame deflector?

7. Sound suppression system? 900,000 GPM of water spray system provides a cushion of water which is directed into the flame hole directly beneath each booster. Water dampens the acoustic waves that can damage the booster along with temperature control. @SpaceX @elonmusk

8. Schematic of Typical Launch Pad

9. Mechanism of Acoustic Generation
See the behavior of the waves generated by the propulsion system. The mach waves reflect back up to the engines.

10. Acoustic waves generated by a deflector. See waves travel away from booster, as intended. Why did @SpaceX not use a deflector with massive water dampening to help prevent collateral damage? @elonmusk

11. Design of Starship Launch Pad Structure. Rebar with cylindrical steel elements filled with concrete. The sheer heft of ~2m (~6 ft) wide steel and rebar columns – soon to be filled with concrete. Where is the water? @elonmusk

12. Debate? @Erdayastronaut @elonmusk

13. A potential re-design of the launch pad for starship? There is definitely more protection for the boosters.

14. Hexagonal design made out of concrete but no water dampening to prevent spalliation of concrete and dynamic loading damage of the boosters? Looks like there is critical damage to the structure.

15. 40 Seconds after liftoff - 3 Raptor engines were damaged with more potential of collateral damage.

16. This is wild. ~1KM away, the debris are seen impact water in the ocean.

17. Finally and for context, here is the design of the sound suppression system at @NASA. Where was the water during the Starship launch? @elonmusk It was hard to see.

Let this be a lesson learned for @SpaceX and learn a lot for the next launch. This is what engineering is all about. Pushing the limits and testing, testing and testing. This is how we learn. Thanks @elonmusk for the great success! @Erdayastronaut @NASA #StarshipLaunch #Starship