SpaceX says helium tanks may be to blame for catastrophic explosion

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SpaceX is closer to understanding last month's rocket explosion at its launch pad.

The company had already targeted the rocket's helium system as being breached.

On Friday, SpaceX said the investigation has been further narrowed to one of the pressurized helium containers, located in the second-stage oxygen tank. 

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On September 1, SpaceX's Falcon 9 rocket (pictured) exploded as it was being fueled for a routine pre-launch test at Cape Canaveral Air Force Station in Florida. Earlier this month, a SpaceX employee was visited the company's competitor United Launch Alliance

SpaceX says it has managed to recreate a system failure in testing and that it can happen entirely through helium-loading conditions. 

'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,' the firm said.

'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, the firm added.

'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,' the firm said.

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.

The unmanned Falcon rocket erupted in a fireball Sept. 1 during prelaunch testing at Cape Canaveral, Florida. 

Both the rocket and the satellite on board were destroyed. Facebook had wanted to use the Israeli-made satellite to spread internet access in Africa.

The SpaceX employee reportedly asked for access to the roof of one of ULA's buildings, which is a little more than a mile away from where SpaceX's rocket launched. The explosion destroyed the rocket and the satellite it was carrying (pictured)

Numerous aviation giants have been pulled into the investigation – including the US Air Force.

The Air Force was called upon two weeks after the blast to inspect the roof of a building belonging to the firm’s competitor United Launch Alliance (ULA) at its facilities in Cape Canaveral, Florida.

The move came after a SpaceX employee reportedly visited the facility and requested access, according to The Washington Post.

ULA’s building is just over a mile away from the site where SpaceX’s rocket blew up on the launch pad on September 1, destroying Facebook’s $200 million satellite.

There has been intense speculation that an object hit the ill-fated Falcon 9 rocket during fueling.

Now, it has been revealed that SpaceX has obtained still images from video that appeared to show an odd shadow, followed by a white spot on the roof of a nearby ULA building, the Post reports.

A SpaceX employee was denied access to the roof upon a recent visit to the facility, and ULA instead called Air Force investigators.

But, after their inspection, nothing was found in connection to the explosion.

‘ULA cooperated with the Air Force’s 45th Space Wing, and nothing associated with the SpaceX accident was found,’ a ULA representative told CNBC.

ULA is a joint project between Lockheed Martin and Boeing and is in heated competition with SpaceX over national security contracts that together are worth hundreds of millions of dollars, according to the Post.

Elon Musk took to Twitter on September 9 seeking ‘support and advice’ as the investigation continues. SpaceX wrote a similar message on its Twitter account as well, which was retweeted by the billionaire SpaceX CEO

It was reported last week that the explosion may have been caused by a large breach in the rocket's helium cooling system.

A preliminary investigation by SpaceX has found the hole in the cryogenic system, which cools the upper oxygen tank of the rocket, occurred just moments before the explosion and appears to have triggered a catastrophic chain of events.

Exactly what caused the breach is still a mystery, the company has said.

A source familiar with the incident reported to the Post that the SpaceX employee told ULA officials that the company was trying to run down all possible leads and that they aren't trying to accuse ULA of anything.

SpaceX's founder and CEO, Elon Musk (pictured), called the failure 'the most difficult and complex' the company has ever had

Just over a week after the explosion, SpaceX CEO Elon Musk took to Twitter seeking ‘support and advice’ as the investigation continues, calling the event ‘the most difficult and complex failure’ the firm has ever had.

And addressing claims that a mysterious object may have hit the rocket, Musk said they ‘have not ruled that out.’

Musk also wrote on Twitter that he was 'particularly trying to understand the quieter bang sound a few seconds before the fireball goes off'.

SpaceX's launch pad at Cape Canaveral Air Force Station in Florida was destroyed (pictured) by the explosion. It has been revealed that SpaceX had still images from video that appeared to show an odd shadow, then a white spot on the roof of a nearby building belonging to ULA

'May come from rocket or something else,' he added.

Earlier this week, Musk said that finding out what went wrong is the company's 'absolute top priority'.

'We've eliminated all of the obvious possibilities for what occurred there,' he said.

SpaceX is leading the investigation with help from the Air Force, NASA and the Federal Aviation Administration.

Despite the investigation, SpaceX has said it intends to return to flight as soon as November. 

ULA (file photo) denied the access to the SpaceX employee and called Air Force investigators, who inspected the roof and didn't find anything connecting it to the rocket explosion. But SpaceX has said they have not ruled out sabotage