Space craft design: musings from the edge
Reading Time: 11 minutes
Preface: My project ‘The Silent‘ is an outlet to explore my take on science fiction concepts and narratives. Through it, I explore not only creative expression but also more grounded aspects such as design and technology in a (far) future setting; The Silent is a curious blending of real world ‘rational’ thinking and pure fiction. This piece is one I have been turning over in my head for some time because, after all, a good spaceship is fundamental to any science fiction escapade! It’s a long one…
I have a crush on Kow Yokoyama’s ‘Maschine Kreiger’ universe. Old as it is (it dates back to the early 80’s), there is something insanely believable about the hardware in it, as if there is an inherent nod to the actual processes of manufacturing and how things work; the rounded forms gracing much of the hardware he designed are very reminiscent of the cast hulls and turrets of vehicles like Sherman tanks and the flight engines, with their cones, pipes and ‘bits’, look like real rockets. I can actually see these things doing what they do without thinking ‘hang on…!?’
And I’m probably enamored with it all because when it come to my views on design depicted in science fiction, I have an increasingly hard time going past the reality of how stuff is made.
Sorry chump, you’re too slow
Everyone loves a good X-Wing, T.I.E Fighter or even better, Star Destroyer. But I have always asked (and I do mean always), just what’s the point of the X-Wing’s wings doing that X thing (or why are they simply profile-less slabs)? ‘Twin Ion Engine’… Ion drives, thrust created through electricity, are totally gutless and always will be, they certainly will never power a fighter craft beyond a crawl, if that. And just what is in that massive Star Destroyer that it needs to be so… big? While George made no bones that his universe was supposed to be emotive, not realistic, everything that came after has at very least taken cues from what he put on screen back in 1978. As a result, what looks good on screen has, more or less, driven the design of fictional spacecraft ever since. And while I get it, increasingly for me, it’s become a… problem.
Oh Star Destroyer, how I love you so. But why do you look more like the Bismark than you do the Zumwalt?
The reality of future spacecraft design will, in fact, be very, very different to what we see on screen. Even in the future when, if, it becomes a normality, the craft we will use to traverse the void will look nothing like the myriad of designs we have become so used to seeing on screen, that we have almost come to accept their ‘design philosophies’ as fact. But from Star Wars up until most recently, there has been relatively little attention paid to the conceptual construction realities of what would be extremely advanced vessels; as if all the manufacturing technology we have today had never existed, and ‘Hollywood’ has gone off and written its own handbook of manufacturing processes (and physics).
So from a designer’s point of view, how do I see spacecraft of the future? I am glad you asked, because here’s my own, opinionated view on the matter…
When you think a spacecraft, when broken down to its most basic, is nothing more than a pressure vessel, you quickly formulate some sort of concept of how its form will follow function. Like a passenger aircraft (or gas cylinder!!), it needs to keep, and maintain, an internal pressure that is greater inside than it is outside; and as long as it does not have to reenter an atmosphere, it has to pay no heed to aerodynamics. Unlike a submarine, probably the closest thing we have on the surface of the earth to a space craft in terms of function, it does not need to withstand external pressures pushing in on it, so its skin, or hull, does not have to be very thick. Basic engineering tells us that the optimal shapes for pressure vessels are round (-ish), like cylinders – see aircraft or submarines. That’s because these shapes distribute internal pressure evenly in all directions against the inner surface of the ‘container’.
What’s not good are box shapes. Not only because they do not evenly distribute internal pressure (and the the flat surfaces will bow and buckle), but also because corners and hard edges are bad. Very bad. A hard corner creates what’s known as a stress riser which, through fatigue over time, a.k.a fatigue stress, can lead to cracks and ultimately failure.
Failures in space are not great.
The Soyez, a perfect example of spheres and cylinders.
Spheres are perhaps the best shape of all for space craft. Besides being the absolute optimal shape for pressure vessels, they also offer the minimum external surface area for the maximum internal space. But ultimately, we’re looking at cylinders, spheres and possible combinations thereof as probablel form factor candidates. We don’t need wings, swoops, or anything even remotely aerodynamic because, you know, the no atmosphere in space thing. So in a nutshell the form factors, driven by function, are going to be fairly organic, not hard edged and polygonal.
So much for flying wedges.
This one hits home to me. As an industrial designer, how stuff’s made interests me. In a big way. And composites interest me in an even bigger way. Now I know that designing spacecraft with lots of panels, with part lines, and splits and stuff stuck on has been the norm for a long time. It looks good, creates visual interest and some say tells a story. But the problem with this way of thinking is that it’s more than a little bit outdated, both from a materials and a process point of view. And that’s today. Right now.
Good design, good industrial design, good aerospace design, good automotive design, is all about less is more. Less parts, less panels, less… anything delivers more performance, more strength. For performance driven machines, where there’s a part line, a split, a bit that’s screwed or riveted, there’s a point of weakness. That’s why we’re now seeing aircraft fuselages being made either as one piece monocoques, or from as few single piece sections as possible made via processes like monofilament winding. Modern monocoque composites technology means the only places you’ll find part lines and panel splits is when something has been joined, inserted like a window, or moves – a hatch, or fin, or flap. Heck, even your family car has as few mechanically joined pieces as possible; our Honda’s have unibody chassis’, meaning they are effectively one piece and very strong.
A Robot monofilament winding a fuselage. Source: Seattle Times
Future spacecraft manufacture will take this thinking to the next level. With modularity as a driving force, not only assemble large craft but also to allow easy construction and configuration, spacecraft will likely be double skinned (like submarines) and have smooth, near featureless composite fibre surfaces, ensuring the most cost efficient, strongest and highest lifespan designs possible.
So how will our smooth, composite space bubbles get around? This is far more interesting than I have time to type, but based on the available reading, there are a few scenarios…
For light level ‘getting around’, chemical reaction engines, not too dissimilar to what we already use today, will probably be still pushing shuttles and small craft. As the laws of physics and chemistry are not likely to change anytime soon, and we’re at the point where we have achieved all we can with terrestrially available fuel, while refinement will continue, the principles of these engines will remain the same. Chemical reaction engines simply just do the job and probably will for some time to come. So while they may seem a bit old fashioned, future versions, while probably smaller and more efficient, will remain familiar.
Going between planets will be the next step, and now things start to become more speculative. Based on who you’re talking to, and regardless of the configuration or type, it’s widely accepted that if we are going to get around the solar system in anything resembling realistic time frames, fusion power is going to be the thing that does it for us. The very nature of what a fusion reactor is will result in all sorts of design consequence for spacecraft design, but in a nutshell, you’re not going to walk through a doorway to check some dials and watch a nice blue glow. The need for crew safety, and survivability if something goes wrong, dictates that fusion powered drives will be outside the craft, so to do any sort of service work, you’re going to have to step outside the front door to do it.
Fusion though is probably the most realistic way to get around space, at the required velocities, using the least amount of fuel load. And while there are several concepts floating around as to how the fusion reactor will actually propel a craft, the net result is we will be seeing bells, de Laval nozzles, hanging out the back of space faring vehicles for a long time to come; because, well, they’ll need them…
So keeping with the form follows function theme when thinking about space craft, for all but the smallest directional thrusters, and where there’s no need to consider atmospheric re-entry, drive systems, chemical or reactor based, will hang out the back, mostly exposed, with maybe some shielding here and there to mildly protect components from accidental collision damage; jamming explosive or radioactive components up against crew and life-support areas does not seem like an overly smart design decision…
From there the next step big is interstellar travel. Hello real science fiction. Worm hole (Einstein-Rosen Bridge) travel is very tantalising but we’ll never know until 1. we find one, and 2. proceed to throw ourselves down it once we do…
That leaves us with the Alcubierre drive, or a version thereof. Mathematically this idea has been postulated as the only workable theory that might actually shunt humans around interstellar space, all with the added bonus that it circumnavigates the whole disaster that is Theory of Relativity… by not being an attempt to travel after than light.
Mmmm. warping space time….
The long and short of the Alcubierre is that the drive creates a bubble which then warps space time around it, allowing it to move from one point to the next, without actually moving – space moves around it. Think about that for a while. ‘Drive’ is actually a loose term when talking about the Alcubierre, as any craft powered by one of these things will not actually move as such, so no warp factor 9 Mr Sulu for you. A interesting depiction of what this sort of system may look like was portrayed in the film adaptation of Carl Sagan’s book, Contact. So in the case of a spacecraft ‘moved’ by one of these systems, we would not see the giant mystical blue-white glow of massive engines sticking out the back, in fact, we probably will not see anything we currently would understand, other than the usual de Laval nozzles for getting around once we have arrived wherever it is we have gone to.
Details, details, details…
So, based on my own musings, we have smooth, clean roundish shapes, more than likely with less cleanly lined engines hanging out the back. But what about the rest?
Like submarines, spacecraft will not need windows and pilots will not sit in a cockpit looking out a canopy; pilots will probably not do an awful lot of piloting in fact. Where windows represent critical weak points, camera and screen technology will all but supplant them. Undoubtably there will be small service portholes but they will not be used for ‘day to day’ viewing, more for peeking out and seeing who’s knocking on the door. Screen and camera technology is good enough today to replace cockpit windows, and indeed Nasa has been trialing this very thing in their experimental X-59, so making the jump to a totally screen driven cockpit/bridge in the future is not too hard; the original Start Trek got that right!
Ancillary equipment, such as communication arrays, radars, expansions etc. will undoubtably be tacked to the outside. Interior space, no matter how technologically advanced the age, will always be prime real-estate so filling it with gear that can otherwise be placed outside would be less than ideal. Our smooth forms suddenly might start looking like bumpy pickles, with domes and pods dotting the skin. And while initially these forms might be integrated in outer skin, with service access from within, over time new items will undoubtedly be added, especially if the service life of craft extends into decades, or longer. Over time, packaged components in domes, pods, spheres, will be tacked on to the surface, giving craft strangely organic and unique looks as they age. In this regard (and only in this regard), the venerable Millennium Falcon could be a good example of what long service life space craft could end up looking like, with all manner of additional ‘bits’ dotting their surfaces.
And lastly….. colour.
This is, and will always remain, a bone of contention for me. I am a child of the golden era fo science fiction illustration, where the likes of Foss and Elson gave us vividly coloured space craft splayed across the vastness of space. While the current reality since mankind’s entry to space has been that craft are predominantly white, black and gold, because of the need to reflect, absorb or shield, and pre Star Wars, cinema were more of less taking cues from reality, there was no reason the craft in Star Wars needed to be…. white. Other than that’s what ‘filmed’ the best.
Though The Guardians of the Galaxy is one of the first departures from this narrative, if it was because of Foss’ involvement in the hardware design could just be a coincidence, my gripe is that everything since Star Wars has more of less stuck to Lucas’ narrative, and spacecraft have been arse boring grey or white ever since. And for no reason.
Show me the colour….!
But considering the need for visibility in space would be a ‘thing’, brightly coloured vessels would make more sense, in fact, the brighter, the better. Military vessels will be probably be matte black, the direct opposite to Star Wars, because black in the black of deep space will be next to impossible to see visually, but the rest? Where colour could easily be part of the manufacturing process, like it is in fibreglassing today, future spacecraft could be made in any colour and pattern possible, with no additional effort or application. Why wouldn’t they be colourful, garish even?
It would be all too easy to fall down the rabbit hole, taking a manic deep dive into ideas and concepts that revolve around the future of space travel. After all, I have not even gone near topics like rotational gravity, or thrust gravity (something the Expanse book series used as a backbone to the design of spacecraft in its universe) and their design implications, or even thought the need for impact protection! Then there’s the difference in types of space craft, and even space habitats, and how philosophies for each will change depending on the usage and purpose. The depth of consideration when it comes to pondering the design of space bound craft is almost bottomless. And let’s not forget, science fiction is as much about the unreal and completely speculative as it is the possibly plausible, which is what makes authors such as Ian.M.Bank’s Culture series, with concepts so foreign that they can only envelope and suck you in.
But I hope this little dip into alternate, probably more rational,future of space craft design might make you stop and think just that little bit the next time you see, or imagine, rollicking space adventures; space craft need not be realistic and boring, but they can be a little bit more understanding of the times, and places, they inhabit.