Next SpaceX Falcon 9 launch delayed until January

Next SpaceX Falcon 9 launch de...
The Falcon 9 rocket set for a January launch is similar to this one used to launch Orbcomm 2
The Falcon 9 rocket set for a January launch is similar to this one used to launch Orbcomm 2
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The Falcon 9 rocket set for a January launch is similar to this one used to launch Orbcomm 2
The Falcon 9 rocket set for a January launch is similar to this one used to launch Orbcomm 2

SpaceX has set back the date for its next Falcon 9 launch until sometime in January. The company says the much anticipated return after a Falcon 9's launchpad explosion on September 1 was delayed to make time for close-out vehicle preparations and complete extended testing to ensure the safety of the flight.

The Falcon 9 carrying 10 Iridium communications satellites was originally scheduled to lift off from Vandenberg Air Force Base in California on December 16 after previous delays due to the accident where a Falcon 9 booster suffered a second stage explosion while refueling. The accident resulted in the destruction of the rocket and payload.

The exact cause of the malfunction has yet to be officially determined, but it's believed to be the failure of one of the helium bottles in the liquid oxygen tank of the second stage. In a media interview, SpaceX founder and CEO said the bottle failure was due to the liquid oxygen solidifying around the helium bottle, where it interacted with the graphite fibers used to reinforce the bottle, but this hasn't been confirmed by the company.

One factor in the delay is that the accident is currently under investigation by a team from SpaceX, the US FAA, US Air Force, industry experts, and NASA. Until the FAA signs off on the final accident report and gives SpaceX a license to fly, the Falcon 9 will remain grounded. In addition, NASA has voiced concerns about SpaceX's use of supercooled liquid oxygen, which requires unconventional fueling schedules.

Source: SpaceX

1 comment
1 comment
To the Author: Please stop using the term "super-cooled". It is a misnomer. Oxygen's liquification temperature is cryogenic, so it is easy to understand a non-science person misunderstanding, especially since anything that is "a lot" is called "super" in the general language. However super-cooled is a very specific thing, and not what is being done in these rockets. They are sub-cooling the fuels not super-cooling them. To understand why this is important we need to look to the definitions:
Super-cooling a substance involves cooling a fluid below the freezing point without freezing. To get an idea of why this is tricky try putting a bottle of distilled water in the freezer it will not freeze, but if you tap it ice crystals form and propagate very quickly until it is solid.
Sub-cooling is the act of cooling a gas until it becomes a liquid. The glass of water on your desk is sub-cooled H2O.
Based on SpaceX's last announcement, where they stated the oxygen crystals or "ice" reacted with the carbon fiber over-wrap on the helium bottles, I believe the trouble they encountered was because no one took into account for the increased reactivity of solid oxygen or the difference in the sub-cooling or liquification temperature of Helium and the freezing temperature of Oxygen. Oxygen freezes at 54.36K, but helium doesn't liquefy until 4K. If they tried to load liquid helium into bottles inside the oxygen tank it could easily have formed oxygen frost on the outside of the bottle, which is wrapped in carbon fiber. This carbon fiber is fairly stable, but solid oxygen is very aggressive at forming bonds, so the Oxygen frost reacted spontaneously with the carbon causing the failure. That's just a theory and we won't know the truth until the official report is released detailing the recreation of the failure.