SpaceX Blast Investigation Suggests Breach in Oxygen Tank's Helium System (reuters.com)

Weeks after a SpaceX rocket exploded inexplicably, engineers at Elon Musk's company have traced the flaw to its source. Space today released the initial results of its investigation, in which it says that a breach in helium system in the Falcon 9's liquid oxygen system caused the sudden flare up. From a Reuters report: SpaceX, owned and operated by technology entrepreneur Elon Musk, was fueling a Falcon 9 rocket on the launch pad in Florida on Sept. 1 in preparation for a routine test-firing when a bright fireball suddenly emerged around the rocket's upper stage. "At this stage of the investigation, preliminary review of the data and debris suggests that a large breach in the cryogenic helium system of the second stage liquid oxygen tank took place," SpaceX said in a statement posted on its website. No one was hurt in the explosion, which could be heard 30 miles (48 km) away from SpaceX's launch pad 40 at Cape Canaveral Air Force Station. The cause of the accident is under investigation.

Comments

Huh.

[Ecuador]

Huh, that doesn't say much, it is only the location of the problem, not the cause. So they say they currently don't have an explanation for the breach but are "investigating a range of possibilities". Is it me or does it look like they are looking into things like projectiles fired towards the rocket?

Re:Huh.

[Bearhouse]

Nope. Putting bits back together after a violent explosion is hard.
Some parts of the jigsaw will have simply burned away, others will never be found.
This is a first step in finding "what"...by finding "where".
Once you've got where, then what, off we go to "why"...

Re: Huh.

[Anonymous Coward]

Seeing as how you cant get within 8 miles of the rocket, that would have to be one serious bullet. I think theyre keeping their options open until they have evidence like any good investigator would.

Re:Huh.

[naughtynaughty]

I think it's you

Re:Huh.

[Anonymous Coward]

Who knew helium is flammable?

Re: Huh.

[rubycodez]

more specifically something like an M102 howitzer (105mm AKA 4.1 inch) would have the range, but I'm pretty sure someone would have noticed one of those bad-ass motherfuckers going off, not to mention it wouldn't just make a "breech" in a cooling system on impact HAHAHA

Re: Huh.

[DanielRavenNest]

Nah, that's too obvious. A sniper rifle fired by a CCAFS security person with money troubles is less conspicuous. Security staff have a reason to be on the base, even patrolling the launch pad area. On the other hand, there's a whole lot of nobody else around the launch pads, for safety reasons. So all he has to do is find a good spot, pop off a shot, then drive over to the launch pad like a concerned security guy would do when something goes boom.

Why money troubles? The people with a motive, like United Launch Alliance, could pay off someone for a whole lot less than what they stand to lose by SpaceX eating their business. Even a six month delay and a few customers moving payloads to "spread their risks" is worth a billion or so in revenue.

Re:Huh.

[Anonymous Coward]

Your Mom cut corners when she fucked that roadie.

Re: Huh.

[Anonymous Coward]

A competitor, or nation state looking to stunt the US private space launch industry is a likely scenario.

Either that, or this is a design flaw in something, and it just ruptured on its own do to the temperature extremes

Re:Huh.

[The Real Dr John]

Helium cooling for liquid hydrogen fuel? Why does this sound so old school rocketry to me? My Estes solid fuel rockets sound more advanced, and I did that in the 1960s.

This is really the best SpaceX can do? I love rockets, I have loved space exploration since I was a kid back in the 60s, but I just don't see Elon Musk as the right way to stellar exploration. It seems like the oligarchy's means to the stars, not something for everyone like the Apollo program.

If we are going to put a national effort into going to Mars and beyond, it should be a fully public space exploration program. If Musk wants to chip in, that's great, but it should not be about him. It should be because he wants to make it happen, the right way.

Re:Huh.

[D00MSlayer]

https://www.askideas.com/media...

Re:Huh.

[Bruce Perens]

Why does this sound so old school rocketry to me? My Estes solid fuel rockets sound more advanced, and I did that in the 1960s.

This is pretty funny. Of course SpaceX is more sophisticated than Vernon Estes and his toy rockets.

The helium is for pressurizing the tank so that the turbopump can receive fuel at a very high volume. In addition, ullage motors cause a small G force on the rocket before the main engine activates in microgravity, so that the fuel or LOX rather than the helium is at the bottom of the tank where the outlet to the turbopump is.

Vernon Estes never had to deal with microgravity and the fact that when you want the fuel, it might have floated away from the fuel intake.

Re:Huh.

[Bruce Perens]

No conspiracy here. The conspiracy folks can go over to here and figure out why the base is now fighting its third fire in a week.

Re:Huh.

[Humbubba]

Jeff Bezos was in Seattle at the time...

Re:Huh.

[naughtynaughty]

SpaceX doesn't use liquid hydrogen fuel

There are multiple private venture rocket companies, including the very successful ULA. The reality is there is a large and growing market for commercial satellite launches. I think that is fantastic.

Re:Huh.

[chmod a x mojo]

Is your sig from first hand experience or what?

Hydrogen wasn't even mentioned in TFS, in fact it says 2 or more times the helium was for cooling OXYGEN.

Furthermore, if you do any half assed research you would know that the engines run on RP-1, which is basically kerosene, also known in generally similar chemical compositions with minor additive changes as jet fuel, and #1 diesel fuel. Much more energy dense than hydrogen as a fuel.

Re:Huh.

[Ol Olsoc]

Its just you.

Re: Huh.

[Ol Olsoc]

Nah, that's too obvious. A sniper rifle fired by a CCAFS security person with money troubles is less conspicuous.

Have you got around to blaming O'Blama yet? The problem with you conspiracy kooks is that your conspiracies get really complicated, really quickly.

Re:Huh.

[Rei]

The helium isn't used for cooling; it's a pressurant. It's lower mass to make a small COPV and have that store your pressurant in it than to have the whole LOX tank be strong enough to withstand the pressure.

It's always bothered me, the concept of having a COPV sitting around in LOX, though. Ignoring the thermal cycling, LOX and epoxy aren't exactly fast friends. We don't make LOX tanks out of composites because composites tend to become impact sensitive in LOX (there've been some attempts, but it's still an active reseach field, not a "solved problem"). Not sure there's that much difference between making your whole tank out of composites vs. having a composite tank inside of one. I don't know what SpaceX does, if anything, to try to protect them, but the general concept has always concerned me.

Re: Huh.

[haruchai]

From Bill Maher

“New Rule: Conspiracy theorists who are claiming that we didn't really kill Bin Laden must be reminded that they didn't think he did the crime in the first place.
Come on, nutjobs, keep your bullshit straight: The towers were brought down in a controlled demolition by George W. Bush to distract attention from Hawaii, where CIA operatives were planting phony birth records so that a Kenyan named Barack Obama could someday rise to power and pretend to take out the guy we pretended took out the Towers.
And I know that's true because I just got it in an e-mail from Trump.”

Re: Huh.

[Catmeat]

That a sniper who's certain to be caught.

Given that virtually every single fragment of the rocket is going to be recovered and examined, most especially in the area where the explosion originated. Evidence of a bullet strike is going to be very very obvious.

The sniper gets caught (the aforementioned money troubles would be a good start in pinning him or her down) and would be offered the choice of ten years or sixty years in jail. The sniper would immediately sing the names of "the people with a motive". A good reason why the paid-sniper scenario is unlikely.

Re:Huh.

[Anonymous Coward]

Archer knew, that's who.

Re: Huh.

[billdale]

SpaceX is stepping on some very big toes: not just the American launch industry, but the Russians, French and others. SpaceX undercuts costs massively... this cannot sit well with the competition, and I suspect Musk has the entire program under extremely tight surveillance to help prevent someone from sabotaging launch systems for cash reward. SpaceX is bound to have a gigantic disruptive effect, and once things settle out in a few years, I truly hope SpaceX is eating everyone else's lunch, so they no longer have the ability to corrupt the system and bloat the space budget the way they have for more than a half-century. I only wish there was someone with the ethics of Musk running for the presidency right now... in fact, hundreds of them to replace the decadent sloths in office right now.

Re: Huh.

[billdale]

LOL!!! Are you KIDDDDINGGG??? You think a, hunk of lead would not melt in the heat of such a conflagration?!? I am not among those that think such an attack is likely or even seriously possible, but you need to rethink your scenario. A lead bullet would NOT maintain its shape for more than a nanosecond.

Re: Huh.

[billdale]

You, sir, are a blathering, full-fledged imbecile. You want to compare your use of toy rockets from more than a half-century ago to massive boosters that have returned four times to barges rocking at sea, and think anyone reading your comment won't bust their guts laughing at your inanity? Since you played with your toys fifty plus years ago, has ANYONE even attempted such a feat after returning from launching dozens of satellites at one time, or docking onto the ISS? It truly burns my butt to see nobodies such as yourself thinking you somehow deserve to criticize anyone who is actually making great things happen, when there are thousands of cretin oligarch carpetbaggers out there doing nothing but sucking the life out of this country. Musk was the one who made light-speed commerce possible with PayPal. It advanced financial transactions a thousandfold. He invested every dime he made in a tremendously bold and risky move to start SpaceX and Tesla... he made them work... both of them... multi-billion-dollar enterprises that are BOTH making huge strides in their respective fields. Musk pioneered a new advanced system of spin-welding that advanced the art of metal joints by decades, a technique used in both his spacecraft and his EVs. He pioneered rocket turbines that are 3D printed, reducing the number of discrete parts dramatically. They are simpler, have fewer joints to rupture, fewer fasteners to fail, are far less expensive and lighter. He pioneered a way to load far more propellant in his fuel tanks than had previously been done, by hypercooling of the liquids. Hudson... DeLorean... Packard... Studebaker... there have been dozens of failed car start-ups in the last 85 years. The Tesla is the first to succeed, and it started at a particularly challenging time--- the beginning of The Great Recession. Musk pioneered the "electric skateboard" concept, putting all the artery cells in, a thick, robust platform below the passengers, lowering the center of gravity dramatically, making the handling especially deft, with the added benefits of enormous cargo space front and back and giving the car the best side-impact resistance ever for a passenger car. It got the highest safety ratings ever--- and this is for a SEVEN PASSENGER SEDAN that can slam you into the seat, pushing you to 60 mph in as, little as 2.5 seconds--- there is no production car today... even multi-million-dollar, two-seat, stripped-down sports cars from Ferrari, Lamborghini and Porsche cannot keep up. You leave yourself open for ridicule... I hope this will help to prevent other witless trolls from making similar comments, when there thousands of riper villains, such as the Koch Brothers, Martin Shkreli, and Heather Bresch to roast.

Re:Huh.

[N3wsByt3]

Well.. feel free to start your own space-company based on your superior technology! ;-)

Re: Huh.

[Agripa]

To refer to a likely obscure quote, "Range safety is very important."

Re: Huh.

[Anonymous Coward]

It was sabotage. I know.

Re: Huh.

[rubycodez]

I'm really interested what rifle you think is going to work at 2+ mile range, unless the sniper wants to die in the fire

Re: Huh.

[rubycodez]

type of weapon for that job would be firing copper jacketed or steel rounds. Evidence of impact would remain anyway. If perp not interested in dying in a fire the weapon would be non-man portable and LOUD like nothing you've ever likely heard

Re: Huh.

[rubycodez]

Obama's original birth certificate sadly was lost in the fire, but don't worry we have county records computer in Hawaii full of replacement ones

Re: Huh.

[Ol Olsoc]

Obama's original birth certificate sadly was lost in the fire, but don't worry we have county records computer in Hawaii full of replacement ones

God keeps ressurecting the birth certificate, but Hellary has had every messenger trying to deliver the truth killed. I think she's up to a village worth now, so there's no one to raise the children any more.

Fear not though, God's armor Joe Arpaio is on the case, and the will of god shall prevail over muslim terror babies from Kenya.

Damn - I've probably started a new conspiracy.

Re: Huh.

[Coren22]

https://en.wikipedia.org/wiki/...

It looks pretty portable to me. Large, but hardly non-man portable.

Hindiburg all over again

[Anonymous Coward]

Shoulda used hydrogen, which won't, explode because it's mostly, water.

Re:Hindiburg all over again

[houstonbofh]

I honestly can not tell if this is a joke, or authentic stupid. Both are equally likely.

Re:Hindiburg all over again

[Anonymous Coward]

Not the best joke ever, but I liked it.

Re:Hindiburg all over again

[Anonymous Coward]

The Hindiburg? Was that in New Delhi?

Re:Hindiburg all over again

[Anonymous Coward]

Oh the outsourced humanity!

Re: Hindiburg all over again

[tysonedwards]

Stupid, naturally safe helium.

Re:Hindiburg all over again

[rossdee]

Well actually the Zeppelin company wanted to use He for the Hindenburg, but the USA wouldn't let them have it. (at the time the USA was the sole supplier.

Am I reading this right?

[willoughby]

"...the cryogenic helium system of the second stage liquid oxygen tank..." makes it sound like they use liquid helium to refrigerate the LOX. Is that really how it works?

Re:Am I reading this right?

[Ellis D. Tripp]

I would ASSume that the helium is used to pressurize the fuel and oxidizer tanks. Would be stored as a liquid to save space...

Re:Am I reading this right?

[Anonymous Coward]

They use helium to pressurize LOX and keep the LOX flowing as its exhausted.

Re: Am I reading this right?

[Anonymous Coward]

Helium is used to fill the space in the LOX tank as the LOX is consumed during launch.

Re:Am I reading this right?

[Mysticalfruit]

No. The helium is used to pressurize the liquid oxygen tank and provide back pressure to the engines. Basically it's the gas that's used to shove the LOX down the fuel lines to the engines as fast as possible.

Also when you're listening to the com loop when you hear "Engine chilldown has begun, they're pumping through the engine.

The prior mishap was caused by one of the struts that holds these tanks to the inner walls failing.
This failure was caused by the tank itself bursting.

I'm suspecting they're going to have to reengineer the COPV helium tanks to be a bit tougher.

Re:Am I reading this right?

[Altanar]

They use the helium to pressurize the oxygen tank. In low gravity with no engines ignited, the liquid oxygen just sloshes around, floating everywhere. They need the liquid oxygen to be at the back of the tank in order to reignite the engine for later burns. Having the tank pressurized with helium pushes the liquid oxygen down to the back.

Re: Am I reading this right?

[Anonymous Coward]

Nothing refrigerates the lox. It is loaded as a liquid. Helium is used to actuate valves and pressurize the propellant systems.

Re:Am I reading this right?

[Arnold Reinhold]

That's not quite how it works. In zero g, just adding Helium pressure to a tank won't accomplish much. You either have to use some kind of pressurized bladder to force the liquid down (ok for thrusters, too big a weight penalty for the main engine fuel and oxidizer) or supply a small acceleration, say from auxiliary thrusters, to settle the liquid to the bottom of the tank prior to ignition. Then He pressure can push the liquid into the main pumps which, in turn, provide enough pressure to force the liquid into the engine against its internal pressure.

Re:Am I reading this right?

[bev_tech_rob]

That's not quite how it works. In zero g, just adding Helium pressure to a tank won't accomplish much. You either have to use some kind of pressurized bladder to force the liquid down (ok for thrusters, too big a weight penalty for the main engine fuel and oxidizer) or supply a small acceleration, say from auxiliary thrusters, to settle the liquid to the bottom of the tank prior to ignition. Then He pressure can push the liquid into the main pumps which, in turn, provide enough pressure to force the liquid into the engine against its internal pressure.

Ullage motors are used to force the propellants to the bottom of the tank...mostly

Re:Am I reading this right?

[DanielRavenNest]

No, the liquid Oxygen is delivered as liquid on trucks, and stored in large tanks at the pad as liquid. The Helium would be cooled to LOX temperature by virtue of being inside a tank full of the stuff. This would lower the pressure of the stored helium, allowing you to put more in the tank, but it's not cold enough to liquefy.

One possible failure mode is something preventing the Helium from cooling down, in which case it could overpressure the tank and it blows up. That could be a problem with getting the LOX into the tank, bubbles around the He tank, etc. Or it could be something simple like a flow valve fracturing. They have all the telemetry data, so I can only speculate.

Re:Am I reading this right?

[AaronW]

Wikipedia has a good description of Ullage motors. Basically they provide a small thrust to force the liquid fuel to the aft portion of the tank prior to firing the main engine to prevent bubbles in the supply.

Re:Am I reading this right?

[Rei]

It's not stored as a liquid, but as a compressed gas in a composite overwrapped pressure vessel (COPV) located inside the LOX tank. And yes, it is used as a pressurant.

Re:Am I reading this right?

[Rei]

Correction: vesselS (plural), not singular - they use multiple.

Re:Am I reading this right?

[Rei]

The weird thing, if it is the COPVs, is... there was so much attention focused on them after CRS-7. It'd be weird if this was the cause. And extremely frustrating, too, as they're not manufactured in-house. SpaceX surely tests the tanks, so they too would bear some responsibility for it getting past their test procedures, if this is the cause. Personally (as I mentioned elsewhere in the comments), having a composite vessel sitting in liquid oxygen always strikes me as a dangerous situation to begin with.... if we were good at maintaining LOX-composite compatibility, we'd be making the stages themselves out of composites rather than aluminum.

Of course, the COPVs aren't the only part of the "helium pressurization system". Still concerning that whatever it was slipped past them.

Re:Am I reading this right?

[RockDoctor]

if we were good at maintaining LOX-composite compatibility, we'd be making the stages themselves out of composites rather than aluminum.

I get that LOX plus composites are an un-good mix. But even with passivation, are aluminium and LOX really that much better? There's still a nerve-twanging amount of free energy in there.

Not an explosion

[ArtemaOne]

It was a fire that spread really really quickly.

Re:Not an explosion

[tomhath]

...and caused a Rapid Unscheduled Disassembly (TM) of the rocket.

Re:Not an explosion

[haruchai]

I'd say it happened right on schedule

Re:Not an explosion

[RockDoctor]

Yes, yes, we all learned the difference between deflagration and detonation the first time we blew up the school chemistry lab. It is, after all, one of the prime purposes of chemistry labs.

Good News Bad News

[DishpanMan]

Good news is that it was not a fault of the ground system and the launch pad so launching from Pad 39 where the falcon heavy is supposed to launch from is an option. The bad news is that it's a second stage issue with the falcon rocket again. This second mishap will make it much harder to qualify the rocket for manned NASA missions and for critical payload Air Force missions.

Re:Good News Bad News

[Anonymous Coward]

Good news is that it was not a fault of the ground system and the launch pad

Not proven. It could have been an issue with the ground system that cause the He tank rupture, either from something as obvious (thus unlikely) as bumping the stack to some trickier like an unregulated pressure surge or flow resonance during the filling process.

Re:Good News Bad News

[Anonymous Coward]

Or anything anywhere rupturing with enough force to fling something through the tank.

Honestly, I don't know that they've found anything other than which tank ruptured first. That is not a root cause unless it can be proven that it did so due to faulty design, construction, or material of the He tank.

Ever since they started asking the public about a ping prior to the fire, my money has been on a projectile directed to the rocket by a competitor or nation state. There are many billions of dollars or even the technological future of countries at stake in this race. The velocity would not have to be very high and even a chunk of ice with fins and computer control (miniaturized version of a guided practice "bomb") dropped from many miles away could do it.

It was a UFO, see youtube

[Anonymous Coward]

Could have been a bird UFO... but pretty cool to watch the timing of explosion with reference to the UFO in any case.

Re:SpaceX should be grounded

[Anonymous Coward]

Thank god you are an engineer and not in management. If engineers like you were running things, no one would be able to drive a car because all the cars would be grounded. This issue was caused by aerospace engineer like you. You say it shouldn't happen, but an engineer forgot to dot the i's and cross the t's and didn't tell management that something should be done about it.

Re: SpaceX should be grounded

[Anonymous Coward]

Jeff Bezos, is that you?

Re:SpaceX should be grounded

[Anonymous Coward]

Then NASA and the Russians and most definitely the Soyuz program should all be grounded permanently as well!

the Shuttle Program should have been shelved back in 87, Apollo should have been shut down as well.

Accidents happen, at the worst possible time. as you said this is something that shouldn't have happened. and the engineers can't be held accountable for. So who is? obviously not SpaceX since you just said the engineers aren't to be held responsible for a failure. so management? sure, I guess, but that doesn't fix anything. Engineers need to be taken to task to find out why their design failed. how else do you fix it? getting management to say "engineer better?" come on be realistic.

Re:SpaceX should be grounded

[Anonymous Coward]

Hello 10010101. Which crappy aerospace company do you work for again? You must be desperate to keep your job to keep shilling here. Not talented enough to work for SpaceX, eh?

Same System Regardless of What SpaceX Says

[Bruce Perens]

Although SpaceX asserts that this is not related to the CRS-7 mishap, it's the same system. On CRS-7 it came loose and released the helium through a broken tube, bursting the second stage nonexplosively (until it self-destructed). This time, it looks like the same tank, a carbon-overwrapped pressure vessel, ruptured. Carbon + LOX + heat of compression from the pressure of the burst = explosion.

This system also leaked during the 2014 Orbcomm misison, delaying the launch by several months.

Re:Same System Regardless of What SpaceX Says

[Bruce Perens]

Um. You really are becoming a troll.

Re:Same System Regardless of What SpaceX Says

[Anonymous Coward]

No, he's just so eager to colonize the universe and with SpaceX's new technology of putting chemicals into a metal tube, it's clear it's happening.

I'm selling my house and packing boxes for my Mars condo. I'm really just bringing my 3D printer because I know I can just 3D print whatever I need by shoveling in Mars dirt into the printer.

I can't wait to explore Mars and its lush vistas teeming with life. Should I pack a granola bar in case I get hungry on the way there?

Re:Same System Regardless of What SpaceX Says

[Anonymous Coward]

Right. Because by posting as AC we can TOTALLY no longer tell who you are.

Re:SpaceX should be grounded

[naughtynaughty]

After Apollo 1 should NASA have been permanently grounded?

Re:SpaceX should be grounded

[Anonymous Coward]

No, looks like yet another intelligent person that saw the light and realized the space industry is on its deathbed. There is no point in building any more rockets and they only continue to get used due to space nutters stuck in the 50s ignoring the advances in technology have made the cost of doing anything in space stupidly expensive compared to sane alternatives.

Helium?

[Anonymous Coward]

Isn't that the same substance used to make gas balloons and we used to distract the damn kids at my grand-nephew's birthday 10 years ago? I heard it was really rare. Why are we wasting it on sending things to space? Everyone knows God never intended for us to leave the home He built for us.

A guy in youtube arrived to the same conclusion

[Anonymous Coward]

Several days ago:
https://www.youtube.com/watch?v=EhdQPaABFK0

Re:SpaceX should be grounded

[N3wsByt3]

"As an aerospace engineer, I can assure you that this is something that shouldn't have happened."

Pheww! Lucky you are an aerospace engineer, or we wouldn't have known that! We were all thinking that exploding rockets were just part of the normal routine! Thanks for clarifying, Mr. Obv... I mean, Aerospace Engineer!