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SpaceX: Stage testing to resume on Falcon 9 in coming days

SpaceX Falcon 9 with CRS 9 Dragon spacecraft launches from Cape Canaveral Air Force Station Space Launch Complex 40 photo credit Jared Haworth We Report Space

SpaceX Falcon 9 launch. Photo Credit: Jared Haworth / We Report Space

CAPE CANAVERAL, Fla. — SpaceX has provided a new update regarding the Sept. 1, 2016, accident that saw a “full thrust” Falcon 9 explode at Cape Canaveral, SLC-40. The company has announced that it has made significant progress in determining the root cause of the accident.

An update provided by the Hawthorne, California-based firm on Friday, Oct. 28, 2016, read as follows:

The Accident Investigation Team continues to make progress in examining the anomaly on September 1 that led to the loss of a Falcon 9 and its payload at Launch Complex 40 (LC-40), Cape Canaveral Air Force Station, Florida.

Since the incident, investigators from SpaceX, the FAA, NASA, the US Air Force and industry experts have been working methodically through an extensive fault tree to investigate all plausible causes. As part of this, we have conducted tests at our facility in McGregor, Texas, attempting to replicate as closely as possible the conditions that may have led to the mishap.

The investigation team has made significant progress on the fault tree. Previously, we announced the investigation was focusing on a breach in the cryogenic helium system of the second stage liquid oxygen tank. The root cause of the breach has not yet been confirmed, but attention has continued to narrow to one of the three composite overwrapped pressure vessels (COPVs) inside the LOX tank. Through extensive testing in Texas, SpaceX has shown that it can re-create a COPV failure entirely through helium loading conditions. These conditions are mainly affected by the temperature and pressure of the helium being loaded.

SpaceX’s efforts are now focused on two areas – finding the exact root cause, and developing improved helium loading conditions that allow SpaceX to reliably load Falcon 9. With the advanced state of the investigation, we also plan to resume stage testing in Texas in the coming days, while continuing to focus on completion of the investigation. This is an important milestone on the path to returning to flight.

Pending the results of the investigation, we continue to work towards returning to flight before the end of the year. Our launch sites at Kennedy Space Center, Florida, and Vandenberg Air Force Base, California, remain on track to be operational in this timeframe.



Jason Rhian spent several years honing his skills with internships at NASA, the National Space Society and other organizations. He has provided content for outlets such as: Aviation Week & Space Technology,, The Mars Society and Universe Today.

Reader Comments

I have to admit, I was speculating the causes, but I also get to say my speculation was all centered on the second stage and the COPV given last year’s failure (whether they were related or not). I also received a lot of negative comments on Reddit and other space sites for suggesting the cause was related to the rocket itself. A lot of people seriously thought it was a ULA sniper! In comment to those people, please don’t place anyone on the pillar of perfection no matter how cool they may be. No one learns by getting a pass on failures.

That being said, I hope they find the root cause. But I’m a bit worried about all of these composite tanks. I’m just a senior in mechanical and aerospace engineering so I don’t have a whole lot of experience in composites, but the history on these tanks haven’t been too positive. At this point they’ just don’t seem reliable enough for manned flights. Hope they can make it work however, it would be a game changer.

The release says they have created “a” failure due to loading, they seem very careful not to say they recreated “the” failure or that it was even a similar failure or under the same or similar circumstances. I am willing to venture a guess that if they shot one of those COPV tanks with a bullet they would have also been able to recreate “a” failure. So bottom line is they state that it is not a confirmed root cause yet and in effect they are saying nothing. Testing those tanks for failure seems like a lot of fun.

Did you not read the article?

“SpaceX has shown that it can re-create a COPV failure entirely through helium loading conditions. These conditions are mainly affected by the temperature and pressure of the helium being loaded.”

So, no, it had nothing to do with shooting the COPV with a bullet. They know they can recreate conditions that result in failures during helium loading, what they don’t have is why the COPV fails in these conditions. I believe that is clearly obvious from the statement. So actually, they have said quite a bit here:

1. The COPV fails when recreating helium loading conditions (cryogenic conditions that have caused problems in the past for composite tanks).

2. The only thing SpaceX is missing is why the COPV fails during these conditions.

At least in quality engineering, a root cause is attributed for a number of reasons: Design, procedures, negligence, etc. So what they are saying is they believe the COPV failure caused the rocket explosion because they can recreate failures with helium loading conditions and at this point is a matter of determining whether there is an inherit problem with the design, they need to revise their procedures, or if someone failed to perform a step on said procedures. Whether this is anything more than what they announced weeks ago when they said they were focusing on the COPV is certainly up for debate.

“I am willing to venture a guess that if they shot one of those COPV tanks with a bullet they would have also been able to recreate “a” failure.”

Sure, but the chances of shooting a bullet miles away from the launch pad on an Air Force base and hitting the COPV which is located within the oxygen tanks located within the upper stage is laughable at best. On top of that, you would have had to breach everything else first but from SpaceX’s own press releases they have stated the failure began with a breach of the COPV.

First lesson: look inward before creating and blaming your problems on someone else. This shows the immaturity of the space X leadership. Lesson ) apologize to United Launch Alliance & the public.

SpaceX never blame to ULA ever. It was the redditor that claim that conspiracy. It’s also based on visitors that claim they were taken to see the destructed pad before seeing Osiris-REX Atlas V. Never SpaceX said that or even offended anyone. Please read their statement again carefully

While SpaceX never outright blamed ULA, they’re the ones who created the whole conspiracy by their own vagueness. Elon’s asinine tweets about small bangs and interviews saying that sabotage was a definite possibility, not to mention the fact that they sent a SpaceX employee to ULA’s building to ask if he could investigate their roof because they saw someone moving around up there. The internet and media was chock full of people saying that a sniper was a definite possibility and anyone saying that there needed to be more scrutiny of SpaceX was drowned out (and quite frankly, still is). If I were Elon or Gwynne, I would be offering ULA an apology. They were absolutely vilified due to their statements.

“While SpaceX never outright blamed ULA, they’re the ones who created the whole conspiracy by their own vagueness.”

“vagueness” : Avoiding irresponsible releases of detailed information before detailed facts are available and confirmed.


Yes, I saw the YouTube video that said that Flappy Bird shot the rocket. That’s the kind of hogwash that comes about when initial folks shoot off their mouths without facts in hand. SpaceX doesn’t have to be vague for folks to make stuff up, jump to conclusions, shoot themselves in the foot, etc. Social media always gets impatient and makes up its own news.

Reading between the lines, it would indicate there was some type of thermal shock to the structural integrity of the CPPV resulting in a crack in it’s structure. To me, there would be a material incompatibility issue of carbon structure bathed in LOX. Carbon (fuel element) immersed in LOX (oxidizer) doesn’t seem like a great idea. As a professional chemist, one doesn’t mix an oxidizer with “fuel.”

My typo in previous post: should read COPV, not CPPV.

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