Slinging payloads into orbit.

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Slinging payloads into orbit.



  • Steve C

    Dumb idea. You’re talking about a spiral roughly 120 ft across, oscillating at 3600 rpm and built, assuming a 1 lb payload, strong enough to withstand 60,000 lb of force on the scroll. Since they used the Punkin Chunkin example, I would point out the the slings are always significantly out-ranged by the air cannons. Gerald Bull’s Space Cannon would be more likely to work, or better yet, a rail gun

  • Scott

    I guess I’m getting old. Seems I remember something like this (and many, many equally odd thought experiments) coming up during an all night, LSD laced think session in the late 60’s. Yes. That’s right! I remember Crosby, Stills, Nash, and Young playing in the background at the time. What amazed the entire group was those little blue creatures running around on the oriental rug – apparently attracted by the scent of pot – as we pondered time, space, and the future of the universe. Ah, yes….Those were the days.

  • Pzatchok

    I want a modified mono rail/rail gun type system with a reusable shuttle platform/train system.

    A gentle acceleration to 3 or 4 times the speed of sound with a nice angle of assent could save a LOT of fuel for a 50 to 100 ton rocket boosted launch vehicle.

    If you could save half the needed fuel load then it would be worth the cost to build it.

    I don’t know the math but how fast would you have to be going at launch to reach about 30 thousand feet with 100 ton vehicle?

  • Edward

    The advantage of having 300 million people thinking about solving a problem is that you get a wide variety of possible solutions. This is similar to Gerard K. O’Neal’s Mass Driver.

  • Pzatchok

    But the slinger is a dead end idea with only one thing going for it. Cheap to operate on a per launch basis.

    It can only launch one type of cargo. Bulk mass like water and air. Even steel girders would have to have be hardened or they would bend under the great forces on launch. And at would be very limited on weight, size and shape.

    If you have to make huge strides in engineering and leaps in technology just to think about having the platform work on a regular basis for a very limited cargo then it might be time to start thinking of a different idea.

    A linear accelerator would work for all types of cargo and a huge variety of masses. And presently only needs scaled up in size and weight capacity. Even if we need to use jet, ram jet, scram jet, or rocket engines to get it to max speed its all technology we are using now.

    Just because a SMART car is cheap to operate does not make it suitable for Nascar races or hauling cargo across country.

  • Kelly Starks

    >..If you could save half the needed fuel load then it would be worth the cost to build it.

    Cost of Fuel/LOx per pound of cargo boosted to orbit with a very high fuel consumption rocket is under $10 per. Not $10,000 – $10! You can drop that to under $5 per pound of cargo delivered to orbit with a bit more advanced multi cycle engnies (which no one bothers with given the total cost per pound is in the $10’s of thousands of dollars per pound.). Its the high overhead and fixed costs (like the billions to tens of billions it costs to develop a decent launcher) not anything related to actually building and operating the launchers that drives launch costs. The virtually non existent launch market, creates horride dis economies of scale. So given this launchers non trivial costs to develop, and stuningly limited launch market – it would be nucompetative with current rocket launchers.

  • Pzatchok

    Then why not just build bigger rockets to get larger payloads to orbit?

    Or launch more rockets?

    I meant mass, more in line with fuel mass than fuel cost. I just wrote it badly in haste.

  • Kelly Starks

    Flying more often would directly lower the cost per pound to launch – so that would be a much better way to lower cost to orbit.

    Assuming there was a market for that much launch to orbit.

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