Airbus patents design for a supersonic ramjet airplane

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The competition heats up: Two Airbus engineers have gotten a patent for a supersonic jet that would use suborbital space engineering, including hydrogen-oxygen engines as well as a ramjet, to fly at 20 to 30 miles elevation.

On a typical flight, it would take off like a conventional plane using ordinary turbojet engines, but once in the air, an open door in the stern of the plane reveals a rocket motor. When this fires, it sends the aircraft into a near vertical trajectory, accelerating it to supersonic speeds.

As the airplane approaches Mach one, the turbojets shut down and retract into the fuselage. On completion of the acceleration phase the plane is now flying at anywhere from Mach 4 to Mach 4.5 at an altitude of 30,000 to 35,000 m (100,000 to 150,000 ft). The rocket motor shuts down and is again concealed as the aft door slides shut to reduce drag. A ramjet now kicks in and the aircraft cruises along its flight path and can cover a range of 9,000 km (5,600 mi) in three hours – the equivalent of Tokyo to Los Angeles or Paris to San Francisco. Meanwhile, the wing fuselage design dissipates the sonic shock wave over 110 to 175 km (68 to 109 mi) and angles it at 11 to 15 degrees so it doesn’t reach the ground. At the end of the journey, split flaps reduce speed and the turbojets take over for approach and landing.

As the article notes, it is unlikely this jet will ever be built, as patented. The patent however illustrates the growing interest by commercial operators of these radical aerospace designs. While this specific design might never fly, many aspects of it are going to start appearing in flying ships in the next few decades.



  • Rod

    At Mach 4.5, I believe it only could be made of Inconel. So, it won’t get off the ground.

  • pzatchok

    Didn’t they try this already with the concord and found it was not quite as profitable as they thought?

    Oh well its their cash.

  • Tom Billings

    “At Mach 4.5, I believe it only could be made of Inconel.”

    That would only be true if they stuck to purely metal alloys. If they use such things as composites developed during the cancelled Aerospace Plane project, with Hafnium Carbide fibers and refractory metals for their matrix, then this should work. Of course, the price goes up. Maybe they can extend the current 3d printing with carbon/epoxy composites to these materials.

  • D.K. Williams

    I can’t think of a viable market for this.

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