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SpaceX wins more NASA manned flights to ISS

Capitalism in space: NASA has now announced that it is buying five additional manned missions to ISS from SpaceX, beginning in ’26.

This new contract is in addition to a February ’22 NASA award that purchased three more Dragon flights.

After a thorough review of the long-term capabilities and responses from American industry, NASA’s assessment is that the SpaceX crew transportation system is the only one currently certified to maintain crewed flight to the space station while helping to ensure redundant and backup capabilities through 2030.

The current sole source modification does not preclude NASA from seeking additional contract modifications in the future for additional transportation services as needed.

The press release repeatedly makes it clear that NASA very much wishes to buy tickets on Boeing’s Starliner, but until it is declared operational it must give its business to SpaceX. Once Starliner begins flying, NASA will then buy seats on it and alternate between the two companies. Until then however this new SpaceX contract guarantees NASA enough flight capacity to keep ISS occupied, even if Starliner gets further delayed.

Regardless, Boeing has once again lost business to SpaceX because its Starliner capsule is not yet ready. In the long run this contract means fewer total flights for Boeing to ISS, which means less profits.

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


  • Steve Richter

    Will SpaceX be upgrading the Falcon-9 to use their new Raptor 2 engines? Would that enable Falcon-9 to lift larger payloads into orbit?

  • Andrew_W

    Do we know if NASA will be paying the same for a seat on Dragon and Starliner?

  • Andrew_W

    Steve Richter, Raptor is the methane burning engine for Starship, Falcon burns kerosene.

  • Jay

    The costs per seat are:
    Dragon – $55M
    Starliner – $90M
    Soyuz – $86M, I am sure they want that in rubles now.

    This info was from a <a href=""article.

  • Jay

    Sorry, forgot the > in the link.

  • Steve Richter

    “… Raptor is the methane burning engine for Starship, Falcon burns kerosene. …”

    If Falcon 9 was redesigned to use the methane burning Raptor, would it have more lift capability? Would NASA require a new round of testing to send crew dragon to the ISS on top of a raptor 2 powered Falcon 9?

  • Patrick Underwood

    Steve, kerosene and methane have very different characteristics, including boiling point, density, and mixture ratios with LOX. There is no financially practical way to redesign F9 for methane and Raptors.

    Musk has been very clear that F9 development is done, and it’s all Starship now.

    But let’s remember what a magnificent accomplishment F9 really is. It completely upended the global launch market, bringing the US from pretty much last place to dominance. It broke the expendable paradigm, leaving the entrenched providers (formerly pointing and laughing) looking at the ceiling, wondering how they ended up in this hospital bed. Even the DoD now contracts flight-proven F9s for its missions.

  • john hare

    Should it prove desirable to have a Falcon class stable mate for Starship, I sure a more efficient vehicle could be designed around the Raptor 2. It would be interesting to see the trades on such a vehicle. Much higher Isp, fewer engines first stage, and a more capable second stage. I consider it possible that Starship/Superheavy is just too large for some missions and launch sites.

  • pzatchok

    The next Falcon upgrade is already proven and operational.
    Falcon Heavy.
    After that you get into the Starship area.

  • Edward

    Steve Richter asked: “Will SpaceX be upgrading the Falcon-9 to use their new Raptor 2 engines? Would that enable Falcon-9 to lift larger payloads into orbit?

    The short answers are NO, and YES.

    The longer answers:

    SpaceX is interested in completely reusable launchers, such as Starship, so Falcon 9 is going to become mostly obsolete once Starship is operational. Falcon 9 did a tremendous service in showing SpaceX how to do reusability and showing the world that reusability was not only practical (many engineers thought reusability would not be practical, as the Space Shuttle showed them) but is enormously profitable, at least for larger launch vehicles.

    Hypothetically, a Falcon with the higher efficiency Raptor engines (which would require radical redesigns) would need three or four Raptors, the total propellant weight should be lower, so, yes Falcon 9 should be able to lift heavier payloads to orbit. The fairing determines maximum size.

    With a Raptor engine, the Falcon 9 upper stage would be much more efficient than it is now. This efficiency would allow for less propellant and would allow for a greater payload weight. Just upgrading the upper stage with a Raptor would allow for Falcon 9 to lift more. Upgrading both the booster and the upper stage would allow for even more payload weight.

    Falcon becomes obsolete because Starship is being designed to launch four times the weight to low Earth orbit and to do it for much less cost — per launch — to the company. Starship is also using lessons learned from Falcon 9 in order to have a faster turnaround time for each vehicle. Depending upon the actual flight performance, SpaceX hopes to increase Starship’s total payload capacity to six times as much as Falcon.

    If Starship works as expected, upgrading Falcon 9 with Raptor engines would not be practical enough to break even with the development costs.

    The real question is: how long will it take for the rest of the world to improve on Starship? SpaceX has made compromises and tradeoffs on Starship that leave plenty of room for improvement.

  • Ray Van Dune

    Almost embarrassed to ask this, but could a Falcon / Raptor SSTO be possible? What a workhorse that would be! Of course I mean a Falcon (highly) derivative, but still the economics might be awesome!

  • Trent Castanaveras

    Ray Van Dune:
    Here Tim Dodd, the Everyday Astronaut, gives a brief rundown on the pros and cons of the SSTO concept.

  • Andrew_W

    Thanks Jay.
    I guess the Starliner must have larger more comfy seats or superior in flight entertainment to justify NASA forking out $35 million per passenger.

    If Falcon sized rocket were to use methane burning raptor engines it would be a new design from the ground up to accommodate the different fuel, different propellant ratios, lower density cryogenic fuel, higher Isp etc.

  • Andrew_W

    Correction “$35 million MORE per passenger.”

  • Edward

    Ray Van Dune asked: “Almost embarrassed to ask this, but could a Falcon / Raptor SSTO be possible?

    Good Question.

    Tim Dodd didn’t go into the math and theory very much. The main problem with SSTO is the very small amount of payload that a large SSTO rocket can get into orbit, so using SSTO to take space station modules to orbit does not work out well. However, with satellites being so small, these days, SSTO may make more sense than when they tried VentureStar (X-33), Delta Clipper (DC-X), and other SSTO ideas.

    Wikipedia talks a little about it, but I missed the part where they show that the payload to orbit is less than 1% of initial mass, yet conventional rockets are get 2% or more. For example, the Saturn V was 3% sent to lunar transfer orbit.

    Before SpaceX, rocket engineers were optimizing for this mass ratio, but SpaceX optimized more for the price to orbit, which is what the commercial customers care about. The Falcon 9 currently has a mass ration of 3% when reusing the booster and about 4% when expending the booster, The cost per pound is less than $2,000, a price point that the customers thought, back in the 1990s, would increase the demand for transportation to space. Considering the greater number of satellites now going to space, the customers seem to have been correct.

    The major advantage of SSTO is the reusability of the launch vehicle, rapid turnaround, and the resulting reduction of the cost of launch (the assumption is that refurbishment between launches costs less than construction of a new rocket, but the Space Shuttle had failed to demonstrate these concepts), but Starship achieves total reusability as a two-stage-to-orbit launch vehicle, accomplishing two major objectives: reusability and lower cost, and hopefully even the rapid turnaround goal.

    Tim Dodd mentioned Skylon, which is air breathing for a large amount of time in the lower atmosphere, so it may be a successful SSTO, because it does not have to carry as much heavy oxygen, making the initial mass lower than it would have needed to be, so it may be a SSTO with a low price per pound.

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