SpaceX: There’s Trouble In The Attic!

Summary: Starship Test Flight 7 was mired by the loss of the vehicle shortly after hot staging. We take a critical look at the official narrative regarding the mishap and call out SpaceX for failing to fully identify the root cause.

Transcript:

SpaceX: There’s Trouble In The Attic!

Welcome to the Edge of Space.

I’m your host, Randall C. Kennedy, and today we’re talking about attics and all the crazy stuff people find in them.

Sometimes, it’s just cobwebs and old photos. Other times, it’s that crazy aunt that everyone thought passed away back in ’94.

But in the case of SpaceX and their Integrated Flight Test 7, the stuff they found in Starship 33’s attic was a lot stinkier – and a whole lot more dangerous.

I’m talking about gas. Specifically, the kind of gas that tends to leak from rocket propellant tanks.

And though my crazy old aunt Mable could fart up a storm at times, her emissions pale in comparison to the kind of methane and oxygen hellscape that exists inside of a typical SpaceX launch vehicle.

That’s because both Starship and its heavy-lift rocket booster buddy, Super Heavy, burn a mixture of O2 and CH4 as their source of thrust.

And though not as unstable as the Hydrogen burned by some other rockets, both of these gasses still get a bit ‘splodey’ when put under tremendous heat and pressure.

Which, according to SpaceX, is exactly what happened inside the “attic” of Starship 33.

But before we get into the gory details, please take moment to like this video and subscribe so you never miss an opportunity to gaze upon my rugged, bearded visage.

Now this “attic” is not what you’re probably picturing right now. No foldable ceiling ladders or hidden doorways to shadowy staircases.

A Starship “attic” is actually a void near the BOTTOM of the vehicle, between the liquid oxygen tank and the aft heat shield.

Normally, this area is just empty space. But after some rough housing on the way to orbit…

“It told you boys to BEHAVE!”

“the adjacent fuel tanks apparently sprung a leak, filling the “attic” with propellant gasses.

It doesn’t take a rocket scientist to figure out what happened next. First there was a smaller explosion, taking out one of the ship’s raptor engines and signaling the first sign of trouble.

Then came reports of fires in the “attic” followed by the BIG explosion, most likely the flight termination system kicking in.

And…that was all she wrote for Ship 33.

It disintegrated into a gazillion pieces, putting on a tremendous light show over parts of the Caribbean as its bits and bobs reentered the atmosphere.

Now, it would be easy to just chalk this whole debacle up to an unforeseeable series of unfortunate events.

Lemony Snickets!

However, for some reason, the thought of letting SpaceX off the hook so easily doesn’t sit quite right with me.

Because, frankly, I’ve still got questions.

For example, after at least four prior successful Starship flights, why did this one decide to blow up?

The initial answer, and the one that most knowledgeable observers defaulted to, is that Ship 33 was a new design – a so-called “Block 2” Starship.

So, any significant deviation from previous test flights could potentially be attributed to some modification of the relevant engineering.

And, hey, as answers go, this sounds entirely plausible. And also, very convenient.

As I’ve stated in the past, I’m no idiot…

While the “Block 2” Starship design is indeed a significant departure from Block 1, it isn’t fundamentally all that different, at least structurally.

After all, both designs are basically great big vertical cylinders with a bunch of horizontal separation “domes.” These “domes” break up the internal volume into a series of propellant storage tanks.

And though the size and position of these “domes” may have changed a bit between ship versions, the overall structural design principles should be the same. Right?

So, then the question becomes: Why didn’t they leak before?

According to SpaceX, Ship 33 sprung a leak because of an “unexpected harmonic response.”

Or what non-engineering folks might call a VIBRATION.

Basically, the vehicle shook so damned hard during the trip to orbit that something broke – or, to put it another way, that crazy, gassy aunt in the attic had a “screw come loose” – or something.

But, again, this all begs the question: Why now? I mean, what was so different about this launch that caused the mysterious “harmonic response?”

It wasn’t the booster. IFT 7 flew with the same generation of booster – in this case, Super Heavy Block 1 Prototype #14 – as the previous flights.

The truth is, SpaceX engineers aren’t quite sure, themselves. Which is why they’re trying myriad quick fixes, from additional venting within the “attic” to tweaking the vacuum raptor fuel lines and propellant temperatures to adjusting how much thrust is applied and when.

However, none of these fixes seem to address the fundamental problem: There’s a whole lotta shakin’ goin’ on during a launch, and for some reason this particular vehicle fell victim where previous ones did not.

Now, far be it from me to second guess the geniuses at SpaceX. After all, they’ve got access to all sorts of internal data that are outside the purview of amateur space sleuths like me.

However, I can’t help but think that SpaceX is trying awfully hard to gloss over this whole unfortunate anomaly, and that simply addressing the symptoms without identifying a root cause feels a bit like cracking the attic window when what ole’ Aunt Mable really needs is a colonoscopy!

Anyway, thanks for watching. Be sure to like and subscribe and hit that notification bell so you’ll be…well…notified when my next space-related rant becomes available.

And until then, remember: Don’t look up! Because manholes aren’t always covered.