SpaceX's Starship SN4 prototype explodes after rocket engine test

Space.com ^ | 29 May 2020 | Tariq Malik

[amorphous]

SpaceX's latest Starship prototype exploded just after an engine test Friday, erupting in a dramatic fireball at the spaceflight company's South Texas proving grounds.

The Starship SN4 prototype exploded shortly before 2 p.m. CDT (3 p.m. EDT) at SpaceX's test facility near Boca Chica, Texas according to a video provided by the South Padre Island tourism site SPadre.com. The explosion occurred about a minute after a short test of its Raptor rocket engine, but it was unclear what caused the conflagration.

[VanShuyten]

They turned off the engine after the short test, but they forgot to turn off the gas?

[ExSES]

In the early days of the space program there were plenty of failures.

Remember them well! Viewed them from the beach just South of Patrick AFB from 1955-1961! Launches were all "Top Secret" yet..., the beaches mysteriously became packed when launches occurred!

[amorphous]

Lol, Uh, NASA probably abruptly entered their quarters and promptly removed all TVs and electronic devices leaving them wondering, WTF...:)

[amorphous]

It did seem like more venting around the bottom than usual.

[markman46]

ya, its even better in slo-mo as the pipe is flying off to the left, fire burned for a long time

[75thOVI]

The Nasa Space Flight channel on YouTube has been covering all the activity down in Boca Chica like a coat of paint. There is a woman down there name of Mary Pointer, who was about 2 miles away with a professional quality telephoto lens filming at the time of the RUD. I saw exactly what you saw, and was about positive that the flare stack touched off the methane cloud. However, the NSF guys played Mary’s footage back frame by frame. At 30fps, about 2 frames before the Earth Shattering Kaboom! There is a small flame coming from underneath the skirt. You can actually see, in one frame, the shock wave from the vehicle moving past the stack. I’ve not been able to find a screen shot. Check out Nasa Spaceflight.com, or LabPadre. I’m sure they’ll have more and better info than any of the LSM.

[BradyLS]

True. And that’s why you test. To find the failure points and fix them.

[amorphous]

Interesting. I'd like to see that footage. I did find someone's camera from another angle which shows the vapor cloud approaching the flare stack, engulfing it and slowly begin rising toward the flame. Then the explosion occurs. What gets me, is you can still see the top of SN4, even after the ignition at the stack, and a flame front from the stack to the rocket or visa-versa is clearly present. If the ignition occurred underneath rocket, it would seem the flame front and explosion would be obscuring SN4 quicker.

Looks like SN4 or support equipment sprung a pretty big leak a short time after the static fire, near the base of the rocket body, which led to the fire/explosion.

This image from the video I mentioned shows both the flame stack and lower part of SN4 engulfed. The explosion/flame front hasn't reached the top of SN4 however.

The image below shows the explosion/flame finally engulfing the top of SN4, but it has left the flare stack. One would think that if it had started underneath the rocket body, the explosion/flame would reach the top of SN4 at about the same time it reached the flare stack and beyond. Not doubting you saw what you saw, but something is odd here and that's what I'm curious to understand. :)

Ref. links:

https://youtu.be/z1f5-gkgDII

https://www.youtube.com/watch?v=O5Hdca8hov0

[minnesota_bound]

I am guessing the 2 astronauts whose flight was scrubbed due to weather are wondering about their rocket flight....

[BobL]

Hopefully they remember to tighten the #3 hose clamp for the next test.

[75thOVI]

Why? The Falcon 9 rocket has shown itself to be extraordinarily reliable. SN4 was a test article that was either going to blow up, crash, or get scrapped. Have you seen how many Atlas rockets they blew up before they strapped John Glenn’s butt to one?

[SunkenCiv]

Whoopsie!

spaceXcentric’s my favorite, he’s on task, structured, and unlike some of the YouTube yokels doesn’t talk at the outset regarding the topic of the vid and then spend ten minutes on a series of uninformative and unentertaining tangents. I won’t name names here. :^)

SpaceX’s Starship Explodes After Test | SpaceX in the News - Duration: 7 minutes, 3 seconds
https://www.youtube.com/watch?v=Zf6vtbgDbCY

[amorphous]

Lol

[amorphous]

Found it... Scott Manley has done an excellent job in presenting exactly what might have occurred. He also has the point of ignition from Boca Chica girl's footage. It did start beneath SN4. The detonation speed was apparently supersonic along the ground, which explains the speed differences. Scott has compiled much excellent footage and does a terrific job of narrating what is going on in each:

What Can We Learn From The Explosion Of The Latest SpaceX Prototype?

https://www.youtube.com/watch?v=BCUYG5SonCY&app=desktop

[amorphous]

Ping to all on the thread to the video by Scott Manley, who IMO does a good job of breaking down what led to the RUD of SN4 for those interested.

Video linked at bottom of post# 54.

[Secret Agent Man]

I don’t know.

The older rockets with much less computer power and less complexity behind them were still touchy, but now you add in so much more computer everything and make it so much more complex.

Just seems like its so much more easy to have a failure.

[amorphous]

I’m concerned with how far they’re pushing current materials technology. The thinness of those tanks for their diameter, and amount pressure they contain is right on the edge. And I’d like to see them rethink giving the nose section some sort of escape ability for future human occupants.

[SunkenCiv]

Yeah, I love his vids as well.

[Secret Agent Man]

i agree