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A FAA waiver granted to SpaceX for its next launch outlines details on the company’s effort to recover the first stage for reuse.

The competition heats up: A FAA waiver granted to SpaceX for its next launch outlines the details of the company’s effort to recover the first stage for reuse.

The first stage will coast after stage separation, and then perform an experimental burn with three engines to reduce the entry velocity just prior to entry. Prior to landing in the water, it will perform a second experimental burn with one engine to impact the water with minimal velocity. The second stage will coast and then perform an experimental burn to depletion.

Elon Musk has said that they will be experimenting with bringing the first stage back safely with each launch of the upgraded Falcon 9 rocket. This waiver now gives us the plan for the first launch. It also shows that they are also considering recovery of the second stage as well.

Genesis cover

On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

 
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.


The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
 

"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News

4 comments

  • joe

    So, does an inversion layer cause an increased risk to the rocket or is this just a function of if the rocket explodes that there is more collateral damage on the ground?, very interesting, I never realized that something as simple as an inversion layer would have an impact on a launch!

  • Tom Billings

    At a guess, this is not because of the Falcon 9, which burns LOX and Kerosene, but because the Dragon still uses the old Nitrogen Tetroxide/Hydrazine combination for its attitude control thrusters. Hydrazine is a deadly poison that kills people when Protons crash in Kazahkstan too near a village. Nitrogen Tetroxide cleverly settles on the mucous membranes of your throat and lungs, and reacts with the water there to make nitric acid.

    Anything with several hundred kilos of that combo is cause for worrying about an inversion layer getting the vapors from an explosion trapped near the ground. They are hypergolic, and react so fast that 2 large volumes of them smacked together will react at the surface hard and fast enough to blow the vast bulk of it into two separate clouds, both of them deeply unfriendly to anything living.

    I could really wish the newer NOFBX monopropellants with performance equal to Hydrazine/Nitrogen Tet. were certified when the design of the Dragon started.

  • Tom,

    You might be right in general, but the waiver was specifically for the next Falcon 9 launch, which will not have Dragon on board.

  • Tom Billings

    Yup! Gotta watch that more carefully. Shrouds are *not capsules! :-)

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