Feb 282012

I have recently been obsessively hammering away at the Nuclear Pulse Propulsion book. 12 to 18 hour days, where I get *maybe* half a page done (either via text of CAD work). Next on my agenda is to re-read Niven/Pournelle’s “Footfall” (beginning right after I log off), and to start working on a 3D CAD model of the Michael. I recently thumbed through the book and found some of the descriptions… they’re pretty vague. My starting point will be the Spadoni diagrams, but I’m not going to slavishly stick to them if I think things should be otherwise.

The CAD work will be open to public discussion. Attempts to contact Niven and Pournelle to ask about whether they’d be willing and available to critique have failed to get a response, so this will end up being “non-canon,” I guess. One of the big problems right off is just how big the Michael is. There is a description of a segment of the pusher “dome” sitting across some docks… and being two yards thick (Orion was to use a pusher plate that in the giant-size vehicles would be several *inches* thick). And page 523 has one of the aliens describe the size of the ship as “twice eight-cubed srupkithp.” On page 195, one “srupk” (the plural of which seems to be “srupkithp”) is defined as 5.8 feet. So… the size would seem to be roughly 2 X 8X8X8 X 5.8 feet, or 5939 feet… 1.23 miles/1.8 kilometers. This is way too big; this was confirmed around a decade ago when I had about three milliseconds of face-to-face time with Pournelle at a sci-fi convention and he looked at me like I was a particularly ugly and intellectually challenged bug when I raised the numbers. But that’s all I have currently. If anyone has ideas, suggestions or sketches of yer own, here’s the place to put ’em forth.

The alien ships in “Footfall” are also nuclear pulse craft, so they’d be relevant as well, but I don’t recall much in the way of descriptive details about them.

 Posted by at 2:26 am
  • BScCollateral

    Perhaps “twice eight-cubed srupkithp” is the ship’s volume?

    • Anonymous

      Unlikely. The aliens use a base-eight mathematical system; “twice eight cubed” would be conceptutally similar to a human saying “twice ten cubed” for “two thousand,” although it would obviously be numerically different.

      Under the circumstances in the story, the simplest explanation would be that the alien in question was simply *wrong.* But that’s kind of a cheat.

  • If I may: please don’t use the Spadoni drawings. They look too ‘Hollywood” — nothing like the utilitarian look of an actual naval vessel. Remember the ship is “one big kludge”, thrown together in a desperate rush, not a sleek, cool-looking ILM design. I always pictured the Michael as being a long, rectangular block with chamfered edges, topped by a simple right cone with a rounded tip. The shuttles hang off two sides, the blowpipes off the other. Missiles are in VLS boxes sunken into the hull; 16″ guns are mounted on barbettes protruding from same. The shock absorbers are straight up and down, not tilted all over as in the Spadoni design. the whole thing should have the plain, blocky, dignified beauty of an actual naval warship rather than the swept-back slickness of a special effects miniature.

    It should also have room somewhere for big, US-Navy-style hull numbers.

    It should look like what it is — an overengineered, brute-force product of shipyard engineering, a balled-up flying fist.

    Just my opinion, of course.

    • Anonymous

      So far as I know, Spadoni’s drawings are the only ones that anyone has tried to put together. I’ve seen a few scratchbuilt Michael-models… all based on these drawings. I’ve never seen an entirely independent vision of it.

      I’ve started re-reading the book. It’ll take a while to get through, but I’ll take every mention I can to try to envision the thing… but the Spadoni drawings do have precedence, and they were apparently signed off by Niven (AIUI). The shock absorbers are an obvious area for a fix, though… not only should they be parallel, they should also be the *same.* One slight advantage that I do have is a single sketch from Douglas Aircraft showing the business end of an Orion -type vehicle with a thick dish and around-the-rim bomb projectors.

      • Ed H.

        It’s been a while since I read the book, but heat rejection for the shock absorbers would be a huge issue. Both the station and the shuttle had huge radiators, and they were rejecting a lot less heat than a multi-thousand ton vehicles accelerating a a gee+ using nuclear bombs. I suppose you could assume that the absorbers were cooled by steam, since steam was used for the attitude control (right?) but then you need more consumables (water storage tankage).

        • Anonymous

          As memory serves, Michael had a whole bunch of ice on board (vaguely recall it being described as an “iceberg,” but I could be wrong).

          Anyway, heat rejection for the shock absorbers would be a trivial matter. yes, the gas within them would get damn hot when they compress… but then they’d immediately cool off when they expand. Friction and thermal transfer of the generated heat through the walls would present a thermal control challenge, but that’d be penny-ante compared to getting zapped with lasers and nukes.

          • Ed H.

            I think we’re talking steady state heat rejection in the hundreds of MW here.

            A lot depends on assumptions about weight and pulse repetition and stroke, of course. I recall reading somewhere that this was still in debate when the program was closed down.

            A warship, expecting damage and externally applied “heating” would have to have a lot of redundant capability.

          • For the past few months I’ve been “designing” (read daydreaming) about the ships and tech of _Footfall_, especially in light of what we know today, about 25+ years after the book was written.

            And I tell you, I agree with Musume-san. Michael would not have looked so “finished.” Blocky. Clunky, yes. It should look more like a flying oil rig than a starship. It would have shit for aerodynamics.

            And if I were to reimagine the thing, here’s what I would change:

            Obviously, the Shuttle Orbiters would go. You’d be better off using the ETs, SSMEs, and SRBs to try to lift the thing to some safe(r) altitude before lighting off the nukes. Replace them with Dragon and CST-100 “gunships” with big service modules full of fuel.

            Instead of a metallic cone on top, why not a snow cone? Why not? Ice makes a great thermal shield. While you’re at it, tile as much as you can in PICA.

            The Blowpipes could be modernized Mercury capsules equipped with the M256 smoothbore gun from the M-1 Abrams. 5-inch sabot rounds ought to perforate digit ships very nicely.

            Missiles might be a space-adapted version of the Patriot, perhaps using both AMRAAM radar and Sidewinder infrared seekers. (the Patriot motors ought to be wide enough for both, and in any case aerodynamics is a non-issue in space) Warheads could be heavy-metal kinetic; or if you’re feeling _really_ naughty, a W-80 set to max yield.

            Finally, under the snow cone, paint a message for the fithp: a huge human foot encircled with the legend: “Guess Where THIS Is Going.”



  • Bruce

    Scott,when I tried to enlarge this like the other drawings in past blogs I could but not this one….
    why? The lettering and the drawing itself would be more better to see for me or is it I am not doing
    something right?

    • Anonymous

      That’s because that’s all the bigger the drawing is. When they were sent to me, the intent was that they would be used in a forthcoming book on the ships of Niven’s “Known Space,” so I wasn’t to post high-rez.

  • Archipeppe

    I always loved “Footfall” novel and it would become a real GREAT model.
    I agree with all the others in not using Spadoni’s drawings because they are far quite off the novel’s description.

  • Bruce

    I used my computer’s image enlarger and it helped.

  • Shayne L.

    I don’t think any of the alien ships used nuclear pulse propulsion. The mothership used a Bussard ramjet and fusion engines. The smaller ships were launched into orbit using lasers and I think they too used fusion engine (s?).

    • Anonymous

      IIRC, the ships used a pulsed fusion system. Much higher pulse rate than Michael, higher efficiency, lower thrust. But I’ll find out again shortly; currently re-reading the book. The aliens have arrived, wiped out the Soviet space station and started pounding ground targets; the Soviet leadership is busy deciding whether or not to freak out and nuke the US.

      Interestingly, I’ve already found a discrepancy. The President goes on TV and gives a little speech which is heard by two different characters… and it’s transcribed differently. Especially interesting is that the discrepancy is in describing the size of the alien mothership.

  • Aldo

    Greetings everyone. I’m the Spadoni guy who came up with the Michael “Spadoni drawings,” so I thought I’d offer a few comments. My friend Winchell Chung recently made me aware of the fact that a Michael discussion was going on here. I apologize for coming into this conversation late. Michael is one of my favorite spacecraft concepts of all time and I’m pleased to see that it’s still generating interest.

    Just so you can put my comments in perspective, let me tell you about myself briefly. I’m an MIT educated mechanical/aerospace engineer with over 30 years of experience designing and developing advanced aerospace vehicle and weapon system concepts. Much of the most advanced stuff I work on is classified and not likely to see the light of day anytime soon. I also manage my own small conceptual design and engineering company and I occasionally do aerospace technology consulting with the motion picture and video game industries.

    Larry Niven and Jerry Pournelle are personal friends of mine. I designed my version of Michael about 15 years ago, working directly with these authors. Together, we iterated the overall design, configuration, and details quite a bit to come up with what you see here. I can tell you that this design definitely reflects what these authors imagined their Michael concept would look like. That said, the gentlemen’s comment regarding my drawings being “far quite off the novel’s description” is interesting. Well, I can tell you rather authoritatively that Larry Niven and Jerry Pournelle wouldn’t agree with that statement.

    However, this does bring up a good point that Scott alluded to. Footfall is a novel of course, not an engineering proposal for a space battleship. You glean details regarding the various Footfall spacecraft from the conversations of characters in the story, many of which are not experts wrt what they are describing. As Scott also pointed out, there are inconsistencies in the descriptions that are either intentional or simply mistakes on the part of the authors. Thus, the design of the Footfall spacecraft are open to interpretation.

    As an engineer and concept designer, I particularly like the way Larry and Jerry write their stories. They provide enough big picture detail to determine the general design direction for their concepts, but leave the smaller details and the system integration issues to anyone willing to take a crack at envisioning their concepts. Fun stuff! So, I think my overall design captures what the authors intended, but many of the details are open to different interpretations, as some of you have done here.

    As I move into discussing some of Michael’s details, I want to note that my primary design goal was to be true to the novel and the authors’ intentions as I understood them. I have my own vision of what a space battleship might look like, as I’m sure many of you have. But that’s not the subject of this design exercise.

    As did Scott, I struggled to determine Michael’s overall dimensions, given the novel’s inconsistencies. Whatever they wrote, Larry and Jerry envisioned the most compact possible vehicle that would get the job done. Note that Scott is showing an older version of my drawing that shows Michael with the shock absorber array fully compressed along with incorrect dimensions. The final dimensions I came up with are somewhat larger, on the same order as those Scott mentions in a separate post.

    Regarding the comment that this is a slick ILM Hollywood design, I think this is reading quite a lot into a hemisphere, a rectangular prism and a shallow cone! Perhaps the commenter is confusing vehicle configuration design with render quality. These drawings were never intended to portray Michael’s actual exterior finish, surface markings, etc. These drawings were created way back when using an ancient vector-based illustration software application called MacDraw Pro. They look pretty awful and it’s certainly not the way I would render Michael today. In hindsight, I should have left them as line drawings and avoided the use of MacDraw Pro’s primitive shading tools.

    Regarding the battleship-derived gun turrets, I agree with Scott’s assertion that the text of the book is vague in this area. But based on my discussions with Larry and Jerry, the authors definitely intended for Michael to include two of the full-up 16-inch Iowa class turrets, as well as some smaller gun turrets, not the guns alone.

    Regarding the Shock absorbers array configuration, I disagree with you guys. Thinking that Michael is a straight extrapolation of the conventional Orion design configurations is incorrect. The primary purpose of the shock absorber array is, of course, to smooth out the “ride” for the payload/passenger portion of the vehicle. Most of the Orion designs were configured for non-military applications, whereas Michael is a maneuvering warship with massive nuclear pumped steam attitude thruster arrays. In addition to primary Orion thrusting, Michael will be subjected to multi-axial mechanical loads that are NOT along the longitudinal axis of the ship. Also consider that Michael’s design incorporates a pusher “shell” that is far more massive as a fraction of total vehicle mass than the typical Orion pusher plate design. When Michael is thrusting under primary propulsion while engaging in combat maneuvers, an angled shock absorber array design is a good choice for handling the inevitable side loads and for stabilizing the shell wrt the passenger/payload “brick”. Consider a high performance off road vehicle, which must provide chassis stability while the wheels and suspension are being subjected to loads from many directions. You don’t see any parallel straight up and down shock absorbers in the suspension system, do you?

    If you look carefully at me design, you can see that that central shock absorber is longitudinal and more massive than the rest. This one is primarily responsible for handling the Orion propulsive loads. Perhaps it should be a bit beefier than I’ve depicted it in the original drawing. The remaining angled shock absorbers handle some of that propulsive load while also providing multi-axial stability. Admittedly, these 2D drawings don’t convey the Shock absorber array configuration that I have envisioned very well.

    Since the time these drawing were created, I’ve discussed Michael with Larry and Jerry on a number of occasions. I’ve reconsidered and refined many of Michael’s technical aspects and I’ve designed a more detailed and representative configuration, including an updated shock absorber array. I’m also involved in creating my own high fidelity 3D model of Michael with a few fellow conspirators. I’m looking forward to sharing that with everyone at some point.

    I can see that many of you have your own interpretations of what Michael should like. I encourage you to move beyond words and take a shot at designing Michael yourself, so we can see what you’re thinking about.

    Scott, I look forward to your Nuclear Pulse Propulsion book with great anticipation!


    Aldo Spadoni

    • Well, so much for that idea.

    • Sferrin

      It’s stuff like this that makes the internet so amazing.

    • Sferrin

      Now that I look at your name, I think I have a drawing of yours at work. It’s dated ’89 and has the Aerodynamicist’s ideal airplane, Propulsion’s ideal airplane, Manufacturing’s, etc. with Advanced Design’s being the Millenium Falcon. 🙂

  • Pingback: “Michael” progress » The Unwanted Blog()