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HyShot Scramjet Test Declared a Success

Posted by michael on from the once-the-scramjets-go-up dept.

An anonymous reader writes: "ABC news is reporting that analysis of the flight data from the recent HyShot scramjet test (covered by Slashdot previously) suggests that the test was successful and that the engine achieved combustion in flight after reaching Mach 7.6. The University of Queensland is also reporting the news."

5 of 253 comments (clear)

  1. BBC link on the story... by MrFenty · · Score: 5, Informative

    BBC story

  2. Photos, other links, and more by danish · · Score: 5, Informative

    There's a ton of photos at http://photos.cc.uq.edu.au/HYSHOT/ and also at http://www.mech.uq.edu.au/hyper/hyshot/HyShot_phot os.html. The former link has some friggin huge jpegs.

    There is also a page about the HyShot program itself at http://www.mech.uq.edu.au/hyper/hyshot/

  3. Re:Actual Destinations? by Oculus+Habent · · Score: 5, Interesting

    Mach 7.6 is right around 2,260 m/s (7,414 ft/s) or about 5,055 mph. It would still take you 5 hours to circumnavigate the globe. Plus you have to consider acceleration time - the rocket doesn't have to worry about killing people.

    Realistically, we probably won't hit Mach 7 in commercial flights for some time, and there will probably be "low-speed" versions for shorter distances. As the article notes (emphasis mine):

    The engine kicked into action on the way back down at 35 kilometres above the earth, with data transmitted by radio until it began to burn up.

    --
    Warning! Error reporting system failu

    --
    That what was all this school was for... to teach us how to solve our own problems. -- janeowit
  4. Re:Mach speeds by jamie · · Score: 5, Informative
    "The thing I don't like about Mach numbers is it's not consistent. Reason being, the speed of sound changes based on your altitude. Higher, where the air is thinner, sound travels slower."

    Untrue. Sound travels slower because the air is colder, not thinner. The speed of sound in the Earth's atmosphere is proportional to the square root of the temperature, nothing else. http://www.allstar.fiu.edu/aero/mach.htm

    Here's an atmosphere simulator where you can pick an altitude and see the speed of sound. As it says, "the speed of sound depends on the temperature and the gas," not on pressure.

  5. Re:Actual Destinations? by mprinkey · · Score: 5, Informative

    there will probably be "low-speed" versions for shorter distances

    Probably not. To understand why requires some knowledge of how a scramjet differs from a normal turbofan engine. There are no spinning parts in a scramjet or ramjet engine. The (sc)ram engine requires a strong standing shock to me maintained in the intake. This standing shock replaces the compressor section of a normal turbo fan. There is a minimum speed which will produce a sufficiently strong, stable shock that will allow this to work.

    The SC part is for supersonic combustion which makes that standing shock also replace the combustor portion of the turbo fan. Chemical reactions and transonic fluid dynamics can interact in very complicated ways. This can make this supersonic combustion unstable. The best way to stabilize it is to go faster and increase the strength of the shock.

    So, to sum up, operating scramjets at lower speeds is more difficult, so if anything, we will probably see them operating at the highest possible speeds that the airframe and aerodynamics will allow.