Another new American rocket engine tested successfully

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.

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

The competition heats up: Sierra Nevada has successfully tested a new rocket engine, dubbed Vortex, specifically designed to fulfill a wide range of uses. From the press release:

These tests demonstrate the ability to transition use of different propellant combinations in the same core rocket engine design with slight changes to accommodate a specific combination of fuel and oxidizer, including propane and kerosene fuels with nitrous oxide (laughing gas) and liquid oxygen oxidizers. This latest development offers customers a suite of engines scalable to higher thrust levels and customer-selected fuel combinations from a single core rocket engine design. ORBITEC’s patented vortex rocket engines utilize a unique swirling propellant flow to naturally cool the engine walls, allowing for the development and manufacture of simpler, low-cost, light-weight and more robust rocket engine systems.

What strikes me about this is that, until SpaceX built its Merlin engine in the mid-2000s, it had been decades since the American aerospace industry had developed a new rocket engine. After the development of the shuttle’s main engines in the late 1970s nothing new was created for the rest of the 20th century. Since Merlin, however, we have seen a string of new engines from several different companies, suggesting that the new renaissance I wrote about back in 2005 is on-going and accelerating.


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  • wodun

    This should help with them competing for the cargo contracts.

  • Tom billings

    The lack of thrust variation in liquid engines, compared to the hybrids specified earlier, will help a lot when they have to maneuver anywhere near the ISS. The thrust needed for abort is large enough that maneuvering near ISS with even a 1 percent variation on total thrust could have been, … more interesting than NASA wanted.

    The vortex-cooled engines are cheaper to make (far less plumbing built into the thrust chamber). They are lighter (if they use N2O as their coolant in the chamber wall vortex, then they’ll have a *very* good absorption of radiant heat from the inner vortex where the combustion takes place), because they should be able to use Aluminum alloys for the thrust chamber. This will be a nice mass reduction for Dream Chaser, even with the 4 thrust chambers needed to match the thrust of the SuperDracos on Crewed Dragon.

    I’m just hoping that once Dream Chaser is demoing the vortex-cooled thrust chambers, and DARPA’s ALASA is demoing the Nitrous Oxide Fuel Blend monopropellant series, we can get Orbitec to combine the two technologies, and begin to develop both small maneuvering engines and larger engines for boosters. That would reduce both costs and mass for thrust chambers and for exterior plumbing in boosters. With specific impulse claimed for NOFB propellants between 266 at sea level and 325 in vacuum, NOFB vortex-cooled propulsion could give enough advantage to new boosters that future competitors for SpaceX will find the first-out-the-gate advantages for SpaceX less of a problem.

    We need new competitors!

  • mkent

    …until SpaceX built its Merlin engine in the mid-2000s, it had been decades since the American aerospace industry had developed a new rocket engine.

    This is not true. Boeing developed the RS-68 engine in the late 90’s / early 00’s for their Delta IV. There may be a new renaissance, but it didn’t start with SpaceX.

  • I hadn’t known about that Boeing engine and stand corrected. Nonetheless, this work by Boeing did nothing to activate this renaissance, because the Delta IV is so expensive to launch. It wasn’t and isn’t competitive, doesn’t reduce the launch costs, and didn’t force anyone else to do the same.

    SpaceX’s work, however, has done exactly that. Their success in lowering cost has forced everyone to follow suit, for the first time in a half century. I still credit them for at least being the first out the gate.

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