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German startup loses prototype of aerospike spaceplane during test

The prototype aerospike test spaceplane of the German startup Polaris Spaceplanes was destroyed recently during its first test flight.

The MIRA I, from German aerospace startup Polaris Raumflugzeuge, was traveling at approximately 105 mph during takeoff when a “landing gear steering reaction” plus a side wind caused a “hard landing event,” rendering the space plane inoperable and it’s fiberglass airframe damaged beyond repair.

Its subsystems remained mostly intact – however, rather than attempt to repair the prototype spaceplane, Polaris has opted to decommission 13.9-foot-long MIRA I to go ahead with the identically shaped 16 foot MIRA II and III design.

Had it flown, it would have been the first flight test ever of an aerospike nozzle. Such a nozzle has been proposed by engineers for decades to take full advantage of the changing atmospheric pressure as a rocket lifts off. Traditional nozzles can only be shaped for one specific air pressure, and lose efficiency as the pressure changes. By using the air pressure to form one wall of the nozzle, an aerospike uses that changing pressure to always function at the highest efficiency.

The company hopes to use this design to eventually create a spaceplane that will take off from a runway, reach orbit, and then return to a runway, all without any additional stages.

Neither of the upcoming prototypes however will be able to do this. Their purpose will mostly be to test the aerospike engine at various altitudes. The company hopes to fly its full scale spaceplane, dubbed Aurora, in ’26 or ’27.

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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.

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  • Trent Castanaveras

    Just going to leave this here:

    Also, although much research has been put into the concept of SSTO, few governments or companies have found it promising enough to pursue it. The draconian requirements of the rocket equation seem to suggest that, barring a yet to be found suite of miracle materials or propulsive elements, although it is possible to put a spacecraft in orbit using a single stage, it wouldn’t be carrying much else with it. The Skylon, an enormous spaceplane concept, would barely be able to field 11 tons to ISS. And that’s if they can even get it to work within such tight margins at all. SSTO from Earth’s surface is right on the edge of possible and may be outside our capabilities for awhile yet.

    I applaud the effort though. Ever since first seeing the DC-Y and X-33 concept proposal videos, I’ve longed to see the all-in-one spacecraft take flight and land again. I wish Polaris good luck!

  • Jeff Wright

    This is why I keep harping about the idea of the rocket AS payload.

    I think launch vehicles should be designed for a different kind of re-use—re-use in orbit as wet-workshops.

    Now Imagine you had a space shuttle orbiter that contained not payload—but oxygen.
    The big hydrogen has its payload on top—has foam covered in an outer layer to prevent popcorning—and is designed to be left in orbit.

    The all LOX orbiter comes back unmanned—with only it sporting a TPS, not a whole Skylon or Starship.

    Or have the orbiter be all Kerosene (denser) and the External Tank all LOX.

    STS/SLS are de facto stage-and-a-half to orbit systems (with strap-ons).

    SSTOs are not a problem.

    Flying a big rocket to orbit is no biggie—-trying to get it all back? That is.

  • Questioner

    I don’t want to diminish the company’s performance, but the thing is more or less a slightly larger model airplane.

  • Questioner: An excellent point that I forgot to mention.

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