[HN Gopher] Akin's Laws of Spacecraft Design ___________________________________________________________________ Akin's Laws of Spacecraft Design Author : Tomte Score : 249 points Date : 2021-01-09 09:46 UTC (13 hours ago) (HTM) web link (spacecraft.ssl.umd.edu) (TXT) w3m dump (spacecraft.ssl.umd.edu) | makach wrote: | "41. There's never enough time to do it right, but somehow, | there's always enough time to do it over." | | There are quite a lot of items on this list that applies to any | kind of project management, software development. | | This is too close to home, will enjoy responsibly. | okl wrote: | In my experience, the opposite is often the case -- The | argument: "We can't start over because we don't have enough | time left" grows in strength as the project approaches the | deadline and is used to justify shoddy work. (You paint | yourself into a corner.) | | I guess one aspect why "agile" stuff is effective, is that the | "last day" (on which it becomes surprisingly easy to make all | the decisions that couldn't be made until now) happens multiple | times and earlier in the project. | Ottolay wrote: | To me this is more of a NASA thing. If a program ends up | going over budget too much it gets cancelled. But the need is | still there, so new program is often started up with a | similar set of requirements. This problem is endemic across | government aerospace programs. | valuearb wrote: | NASA projects don't get canceled for being over budget or | late, they get canceled for being championed by a different | administration. | | Sources: - SLS - Orion - James Webb Telescope - | constellation/Ares V project | lambda_obrien wrote: | It took 24 months of effort to get a particular system to | barely run every hour by some contractors. After 3 weeks, I | rewrote most of it and still have a month left, but it runs | in 5 seconds. I'm having trouble right now convincing my boss | it's better to work on the 5 second version even if he spent | hundreds of thousands of dollars on the 1 hour version. It's | the most annoying sunk cost ever. | karaterobot wrote: | I took him as being sarcastic when saying there was always | time to do it over. He's ironically stating the bad logic | that people use to justify introducing new technical debt. | | At least, that's what I assume, since I've heard this | sentiment expressed in the much clearer phrasing "If you | haven't got the time to do it right, when will you find the | time to do it over?". | | That's apparently the title of a popular book by a management | consultant named John Wooden, but I'm not sure of the | provenance of the quote. | [deleted] | larrydag wrote: | From Elon Musk "failure is an option". My take, if you aren't | failing then you aren't learning. | roughly wrote: | Failure is an option right up until you're doing 85 on a | crowded highway with passengers in the car. | ErikVandeWater wrote: | Depends what kind of payload you have on your rocket. People | or a billion-plus dollars of equipment? Or is it just a test | rocket to see if it can land itself? | JumpCrisscross wrote: | > _People or a billion-plus dollars of equipment?_ | | Requiring no risk of failure for people is a large part of | why we don't launch astronauts much. | | Space is risky. Setting the expectation that astronauts can | never be lost, as opposed to that they are on an exciting | frontier that has its dangers, is out of line with | astronauts' own risk preferences. This has been a failure | of expectations setting by NASA. | ErikVandeWater wrote: | I'm just saying it would be blase to say that "risk is | always an option" in regards to astronaut lives or | billions of dollars of equipment. | scrollaway wrote: | I'm sure it's not just for the sake of the astronauts | though. Losing an astronaut is losing a massive | investment and years of training. | JumpCrisscross wrote: | > _Losing an astronaut is losing a massive investment and | years of training_ | | Practically grounding astronauts for three decades is not | much better. | irowe wrote: | Which 3 decades were astronauts practically grounded? | JumpCrisscross wrote: | Expanding: it should be known when failure is tolerated. | Situations where it isn't ( _e.g._ maiden flight with | astronauts) should follow ones where it is. | | Being the one learning through failure in an organisation not | tolerating it isn't fun. | coldtea wrote: | When the final outcome is important/worth it, failure is | tolerated everywhere. | | Including "maiden flight with astronauts". | | Several test pilots, and astronauts died and we still went | to air/space. | ShroudedNight wrote: | This is a perennially satisfying work. It appears to originally | be from 2003 given the previous time the submission got traction: | | https://news.ycombinator.com/item?id=25698990 | GlenTheMachine wrote: | I was Akin's grad student (I'm Henshaw, of Henshaw's Law). The | Laws go back to the late 1980s, at least. | aweiland wrote: | Your name is familiar. Were you there in the 99-02 time | frame? I was an undergrad employee then working on SCAMP and | later NBV2/RTSX. I helped design and build the big crate on | the deck housing the power, comms, and air supply. | | Such an amazing place to be. | GlenTheMachine wrote: | I was! And I worked on SCAMP II. | aweiland wrote: | Very cool! We probably passed on the deck quite a bit | then. | CraigJPerry wrote: | >> 8. In nature, the optimum is almost always in the middle | somewhere. Distrust assertions that the optimum is at an extreme | point. | | Is it contentious to say we're going through a point in time | where this is not commonly held? | | What I really want to figure out is am I mis-remembering or were | the late 90s / early 00s pretty strongly centre biased? | meheleventyone wrote: | This is the classic fallacy of the middle ground when it comes | to opinions. | | https://en.wikipedia.org/wiki/Argument_to_moderation | | Particularly as "the middle" can be dependent on where the ends | are. The middle ground of American politics is different to the | middle ground of European or Chinese politics for example. | dsr_ wrote: | Let's consider this in the context of engineering, rather than | politics. | | It's not clear that this is a good rule. If you want to get | mass from ground to orbit, the rocket equation means that you | want the least quantity of infrastructure mass that will work, | maximizing the payload fraction. If you're in charge of safety | equipment on an orbital station, you want the most effective | things you can cram in to your mass budget. | | Life support? Whenever possible, eliminate it in favor of | automation. But if you need it, you either want minimal | (emergency only) or maximal (resilient against disasters) to | the extent of your available space/power/mass. | jcims wrote: | You're absolutely right, but I think the point is that the | rocket with the maximum payload fraction isn't necessarily | the best. | okl wrote: | Right, if the optimum is not the maximum/minimum of X, then | you are probably not optimizing for X, or you have additional | constraints. | marcosdumay wrote: | The thing is, you always have more than one optimization | target. | tuatoru wrote: | Another formulation would be "optimising on one parameter means | pessimizing on one or more others". | DrBazza wrote: | What's the one where it's not worth launch an interstellar | vehicle now because one launched in, say, 50 years would overtake | it and arrive first? | NortySpock wrote: | I've never heard it called anything fancy, just the "wait | calculation" or the "wait equation" | | https://www.centauri-dreams.org/2006/11/24/barnards-star-and... | DrBazza wrote: | Thanks! | Razengan wrote: | Why is almost every spacecraft design in reality and sci-fi | "pointed" like airplanes and sea ships, as if it's only going to | move in one direction on one plane? | | I'm guessing it's because of the need to go through our | atmosphere first. | | Wouldn't an omnidirectional saucer-like shape (or spherical for | larger ships) be more practical in 3D vacuum? | frabert wrote: | Because that's what the public expects a thing that flies fast | to look like. Also the Rule of cool applies here. | 4gotunameagain wrote: | In actual engineering, the "rule of cool" only applies when | two options appear to be exactly similar on all other | aspects. Which is almost never. | Razengan wrote: | Even then the Independence Day saucers and Borg cubes and | spherical ships win out in the cool factor. | bluGill wrote: | In SciFi many ships have a military purpose and should be | designed around the guns and the engines. Everything else used | cramed in where there is space. | elygre wrote: | I can think of two: | | * There would often be a need to separate human areas from more | energy rich areas. A pointed solution often allows for this | separation. | | * Current engine design has a "rear end" of some sort, which | then implies "pointing" | phreeza wrote: | If you are going fast enough, my understanding is that the | interstellar medium is actually not that empty and such a shape | might make sense again. At least that is the reason given in | the Revelation Space saga. | yetihehe wrote: | We don't yet need to go through interstellar medium. | Currently vehicles which need to go through atmosphere are | pointy. Vehicles which do not are not pointy (all current | satellites). | phreeza wrote: | The question specifically included sci-fi. | detritus wrote: | and, critically, 'fast enough'. | gmueckl wrote: | Sci-fi shows need designs that are "readable" by the viewer in | split secons. That means unique, distinguishable silhouettes | that also tell you at a glance where everything is moving in a | shot. Pointy designs make that work excellently. | | As for the real world: there are plenty designs that are not | pointy and flying: every satellite, the ISS, the lunar | lander... however, all the designs that interact with earth's | atmosphere have to respect aerodynamics. Thus, just about every | ascent vehicle becomes pointy. Landers are different. The Soyuz | return module doesn't look particularly pointy, for instance. | the8472 wrote: | almost every satellite. | https://en.wikipedia.org/wiki/Gravity_Field_and_Steady- | State... | the8472 wrote: | > Why is almost every spacecraft design in reality and sci-fi | "pointed" like airplanes and sea ships, as if it's only going | to move in one direction on one plane? | | Because they have directional main engines. That does not | strictly necessitate them to be pointy on the opposite end, but | it at least requires some design that can distribute the force | through the ship's body with the minimal amount of structural | mass. E.g. an axial design that only has to withstand | compressive forces, not shear forces. | | A bigger issue is the lack surface area for cooling. Not even | The Expanse gets that one right. | skrebbel wrote: | > A bigger issue is the lack surface area for cooling. Not | even The Expanse gets that one right. | | Care to elaborate? What's "lack surface area" and how does | the Expanse get it wrong? | PeterisP wrote: | Whatever you do with internally generated energy, you | either get it out or it accumulates, overheating you. | | You need 3-10 m^2 of radiators for every kW of power you | use. If your ship is powered (I mean internal power, not | engine exhaust) by a 1MW reactor, then you need radiators | close to the scale of a football field pushing out waste | heat, no matter what tech that reactor uses. | EForEndeavour wrote: | Where does that 3-10 m^2 per kW estimate come from? The | best I could guess based on my shaky grasp of radiation | is to equate internally generated power to total radiated | power using the Stefan-Boltzmann Law: | | https://www.wolframalpha.com/input/?i=1+kW%2F%28Stefan- | Boltz... | | Based on that, you need 3-10 m^2 of radiative surface | area per kilowatt, but that's assuming your equilibrium | temperature is 203 to 275 K (-70 to 2 degC). Assuming I | haven't made some basic mistake, couldn't you decide to | heat part of your surface to some much higher temperature | and radiate most of your internal power out of that part? | PeterisP wrote: | This is what our current spacecraft radiators manage. You | also have to take into account that radiators also | interact with the sun and with the rest of the | spacecraft. | | Of course, you could have a heat pump pushing heat to a | higher temperature surface, some current radiators do | that, but it has its limitations requires more energy for | the pump the higher temperature difference you want to | sustain. | bombcar wrote: | Delightfully counterintuitive given the low temperatures | of space - would it help said ships to hide on the dark | side of the moon and avoid solar radiation? | the8472 wrote: | Scifi ships tend have engines with stupendous power ratings | (Gigawatts and higher). Even with 99% of efficiency they'd | have to shed megawatts of heat. Since there is no | convective or conductive cooling in space your steady-state | option is radiative cooling which is constrained by surface | area, temperature difference and emissivity. You don't have | much flexibility on the latter two. So you need to increase | surface area. The ISS' radiators take up about 200m2 and | can reject 70kW. There are non-steady-state options such as | sacrificial coolants or plain thermal mass but that would | require extra mass, resupplies or additional downtime. In | The Expanse the ships just don't have enough area | considering they're powered by fusion reactors burning | constantly. | rm445 wrote: | What about lasers for emitting waste heat? Obviously | there are practical issues with having powerful-enough | lasers essentially powered by a heat engine, but are | there thermodynamic reasons it couldn't work? | | This question is not 'Expanse'-related but inspired by | David Brin's 'Sundiver'. | NortySpock wrote: | I think you're going to run into problems turning waste | heat into usable energy, because it implies there's a | cold sink already that you can use to convert the | temperature differential into electrical energy to drive | your laser. High end laser efficacy ranges from 30% to | 50%?[1] But regardless, you're asking to get low-entropy | energy out of high-entropy energy, and that's one of | those "you can't win or break-even at thermodynamics in a | closed system" kind of thing. Since spaceships come | conveniently jacketed in a vacuum-insulating outer layer | (i.e. space :) you're still stuck with some variant of | radiative heat transfer, and "a big piece of metal being | used as a infrared heat radiator because we pushed heat | into it using a refrigerator loop) is still the cheapest | option. | | The last option techie that I've ever heard for rejecting | heat already onboard on a spaceship (and this is pure | technobabble from proposals about Star Wars ships massive | power generation needs) would be some magical way to | convert heat into neutrinos, which, since neutrinos can | pass though most matter, could be inside the ship and | still function as a heat rejection mechanism. [2] | | [1] https://www.laserfocusworld.com/lasers- | sources/article/16547... | | [2] https://www.theforce.net/swtc/power.html | blincoln wrote: | There's a writeup here that you may be interested in, if | you haven't seen it already: | | https://toughsf.blogspot.com/2019/10/the-expanses- | epstein-dr... | | The author suggests creating a fusion reaction well | behind the ship, but channeling the useful parts of it in | an electromagnetic field tunnel to create thrust while | dissipating the heat more effectively. Vaguely like | Project Orion, but with a more-or-less continuous | external fusion reaction instead of a series of nuclear | explosions. I am not a physicist, but they seem to have | done their homework. | benlivengood wrote: | > A bigger issue is the lack surface area for cooling. Not | even The Expanse gets that one right. | | This depends on the working temperature of the radiator too. | In theory if area needed to be optimized a (series of) heat | pumps could shed more power from a hotter radiator. | | If future designers want to be cute about it they could stick | a high temperature radiator at the front of the ship as a | headlight and lower temperature radiators in the back for a | tail light. | rriepe wrote: | Mass Effect is the only sci-fi I've come across that touches | on the issue of building up heat in ships in space. | pomian wrote: | Saturn Run, is a really interesting and fun book - by John | Sandford. I highly recommend it, as a successful modern | science fiction book. That topic is really well covered, | with engineers solving all sorts of problems, including | that one. | the8472 wrote: | Banner of the Stars addressed it by cooling peak loads via | disposable coolant instead of solely relying on radiative | cooling. It became a limiting factor during a large-scale | fleet battle. | hyko wrote: | They're not? Obviously many of the spacecraft we're used to | spend a fair bit of time in the atmosphere, but even real | manned spacecraft have come in different shapes and sizes | (usually variations on spheres and/or cones). | hilbert42 wrote: | _" 29. (von Tiesenhausen's Law of Program Management) To get an | accurate estimate of final program requirements, multiply the | initial time estimates by pi, and slide the decimal point on the | cost estimates one place to the right."_ | | I wish I'd learned this a long while ago. Going on some of my | current projects, it seems that a good portion of my brain still | hasn't! | gabia wrote: | Given spacex, this one hasn't aged well | | "39. (alternate formulation) The three keys to keeping a new | human space program affordable and on schedule: 1) No new launch | vehicles. 2) No new launch vehicles. 3) Whatever you do, don't | develop any new launch vehicles." | benlivengood wrote: | Starship is intended to be a dual-purpose cargo and human | flight vehicle and Falcon 9 + Dragon were iteratively improved | through many cargo launches before Dragon 2 for human flight. | | What has likely changed is that there is sufficient demand for | cargo flights to bootstrap an affordable human flight program | on top of it. | shakow wrote: | SpaceX was neither affordable nor on schedule. If you wanted | someone up there cheaply and on time 5 years ago, you should | just buy a seat on a Soyuz. | | However, #39 doesn't say "don't ever develop new launch | vehicles", rather "don't develop new launch vehicles if staying | in budget and on timeline is your priority". | valuearb wrote: | Falcon 9 is the most affordable launch system in history. | It's saved NASA billions through ISS cargo launches. | | And developing their crewed launches has been over a billion | dollars cheaper than Boeing, and successfully launched years | earlier. | dotancohen wrote: | SpaceX did not develop a new launch vehicle for a human space | program. SpaceX developed two new reusable launch vehicles for | transfering cargo, whilst not cutting the corners that could | not be cut if it were used for a human space program. Then when | it came time to put humans on it, it already had a legacy. | | Starship, however, is in fact designed for humans. But it is | not part of a "human space program", rather it is a multi- | purpose vehicle. It is yet to be seen towards which human space | programs it will be applied, but even with the Artemis bid many | aspects of Starship were clearly designed without the Artemis | bid as a specific target. | dwighttk wrote: | I think that one is a round about way of saying "a new human | space program will never be affordable or on schedule" | yetihehe wrote: | It wasn't "on shedule". Also, those launch vehicles were | already old and proven (multiple times even!) when they | launched humans. | JonnyaiR wrote: | Not quite, spacex changed quite a few things every launch or | at least every version, that's why the first falcon 9 is very | different compared to one from today. The one carrying humans | is called block 5 of the full thrust version (version 1.2). | qayxc wrote: | That's not what they meant - SpaceX didn't develop a Falcon | 9M or Falcon X for the crew vehicle is the key here. | HALtheWise wrote: | Notably, SpaceX did not develop the Falcon 9 as part of their | human spaceflight program, and it was in fact not rated for | carrying humans for many years. They instead developed their | launch vehicle as part of a standalone "launch vehicle program" | then later committed to building a human spaceflight program on | top of their existing rocket. Starship _is_ being developed as | part of a human spaceflight program, and we have yet to see | whether this violation of Akins Laws will be justified. | zaphoyd wrote: | I had the opposite thought. SLS/Artemis is a "new human space | program" that includes a new launch vehicle and it is | hopelessly unaffordable and off schedule. SpaceX developed one | of the most affordable human launch systems ever made, in a | reasonable amount of time, by using their pre-existing cargo | launch vehicle. Even Boeing will likely have Starliner, which | also uses an existing workhorse launcher, flying humans before | SLS launches anything. | rozab wrote: | SLS reuses almost everything (with modifications) from the | shuttle program. These are 40 year old designs. Falcon Heavy | reused a 10 year old design (Falcon 9). | | edit: If we count back to the first successful propulsive | landing, the technology was only 5 years old. Falcon Heavy | had been planned since way back in 2005. | larrydag wrote: | I think the only thing reused is the engines. Granted that | is a lot of the engineering. | | https://everydayastronaut.com/sls-vs-starship/ | FlyMoreRockets wrote: | My math shows the technology to be 22 years old. | | DC-X: First flight (and first successful propulsive | landing) 18 August 1993 | | https://en.wikipedia.org/wiki/McDonnell_Douglas_DC-X | | "In December 2015, a Falcon 9 accomplished a propulsive | vertical landing." | | https://en.wikipedia.org/wiki/SpaceX | | See also: | | https://en.wikipedia.org/wiki/VTVL | | Not mentioned in the above link was an amateur group | developing VTVL tech around the San Francisco bay area in | the 90's. IIRC, it was EPRS. FWIW, they also invented a | multi-rotor platform to test their conrol system that | evolved into the modern drone. | | http://www.erps.org | valuearb wrote: | Don't forget that SpaceX Grasshopper flew DC-X like tests | in 2012. Not first by any means, but first for SpaceX. | | https://en.wikipedia.org/wiki/Falcon_9_prototypes | FlyMoreRockets wrote: | Valid point. Also, if one wants to stretch the envelope, | Harold Graham, flying the Bell Rocket Belt, performed the | first rocket powered landing, April 20th, 1961 at Bell | Aerospace, upstate New York. This development footage | opens with that flight: | https://www.youtube.com/watch?v=gxmxbMdToR4 | Isamu wrote: | Agreed, the entire point of Starship development is to make a | new human space program (to Mars) affordable. | marcosdumay wrote: | All of spacex work is on launch vehicles, so I disagree, you | are just reading it wrong. | valuearb wrote: | Also Cargo and Crew Dragons. | Rebelgecko wrote: | And a large satellite constellation | iamtedd wrote: | Just finished watching the latest episode of The Expanse and had | to severely reel back my expectation of 'spacecraft' when reading | this article. | leetrout wrote: | " 7. At the start of any design effort, the person who most wants | to be team leader is least likely to be capable of it." | | That's interesting. I generally have strong opinions about things | I care about and would much rather be the one making decisions so | I can own the outcome, ESPECIALLY negative outcomes. Maybe it's | just a control thing... I'd rather fix my own mess | vvanders wrote: | I think it's largely a function of the intrinsic reason that | someone wants to lead. | | Are they in it for the title or the prestige? Their desire will | as some point run in conflict with the larger program goals. | | Do they do it because they enjoy bringing a diverse set of | viewpoints together to create something that couldn't be | created in isolation? That might have a better chance of | success. | | Unfortunately it's very difficult to determine this externally | without a significant investment in time or otherwise. | christophilus wrote: | " To summarize: it is a well-known fact that those people who | most want to rule people are, ipso facto, those least suited to | do it. To summarize the summary: anyone who is capable of | getting themselves made President should on no account be | allowed to do the job." Douglas Adams | | This has largely been my experience. | moosebear847 wrote: | Strong opinions could be bad at the start, when nobody really | actually knows what the heck is going on. | [deleted] | lordnacho wrote: | > Engineering is done with numbers. Analysis without numbers is | only an opinion. | | With or without numbers, it's still an opinion? | slx26 wrote: | It happens with language. Although you can label both as | "opinions", one of them is, probabilistically speaking, a more | substantiated opinion. | majkinetor wrote: | Not sure why you are downvoted, unless we are in math land, you | might be right. | | Numbers that come from measurements are often not precise | enough, measure additional things, massaged until they fit the | preconceived etc. So its still the opinion pretending to be | engineering. | Tade0 wrote: | I recall 39. whenever someone suggests rolling their own form | component library along with the project - it's pretty much the | same issue. | capableweb wrote: | Well, trade offs right? Rolling their own form component is | sometimes the right decision, depending on context and more. | | See also, #1 and #12 that should be considered in your example | too. | Tade0 wrote: | Perhaps, but in my experience most of the time the project | focus shifts to those components from the application in | question. | teleforce wrote: | Awesome list of engineering wisdoms! | | This one probably the best: | | 36:Any run-of-the-mill engineer can design something which is | elegant. A good engineer designs systems to be efficient. A great | engineer designs them to be effective. | | This statement reminded me of the popular quote on teacher, "The | mediocre teacher tells. The good teacher explains. The superior | teacher demonstrates. The great teacher inspires." | okl wrote: | Unless you can decide what elegant, efficient, and effective | mean for your project that statement is empty. | TheOtherHobbes wrote: | Cheap, fast, good. | | Mediocre: pick one. Adequate: pick two. Outstanding: pick | three. And customers are happy too. | _Microft wrote: | _Elegant_ might be open for debate, but _efficient_ means | good use of needed resources and _effective_ that the desired | outcome is actually achieved. | odonnellryan wrote: | I would say, if engineers can even identify what the | desired outcome is, they are already on the path to being | excellent (or maybe, if they even _attempt_ to identify | what the desire outcome is!) | marcosdumay wrote: | Elegant engineering work is work that has good properties | as evaluated by other engineers and that don't directly | impact the properties non-engineers care about (what | doesn't mean that aren't impacts, just not direct ones). | | I don't think you will find this in any dictionary, but the | meaning is incredibly consistent, even on different | engineering areas and different languages. | simonh wrote: | That's why good teaching is hard. | sokoloff wrote: | TIL that great (and excellent) are _stronger_ adjectives than | superior. Thanks. | hyperpallium2 wrote: | I would say the best teacher listens - how can you direct | someone somewhere if you don't know where they are? | | Of course, only really feasible for 1-1 teaching. | pmdulaney wrote: | "(Nasa's Law) Work flows to the most competent man until he | sinks." | | Yes, sexist, I know. I recall this from many years ago but have | not been able to find an official source. Anyone know? | dotancohen wrote: | > #20 A bad design with a good presentation is doomed > | eventually. A good design with a bad presentation > is | doomed immediately. | | This should be the Y Combinator motto. It is one of the axioms | that is represented here again and again, both explicitly and | implicitly. | sillysaurusx wrote: | Hm? I can't think of any recent projects with good design but | bad presentation. The first half is true, but the second half | seems mistaken in the context of the web. | jaspax wrote: | You can't think of them _because they immediately failed_ , | and thus you forgot about them or, more likely, never heard | of them in the first place. | lisper wrote: | Exactly this. I have a long list of examples, with a one- | to-one correspondence to large capital losses I have | incurred. This is not a coincidence. | OCISLY wrote: | > doomed immediately | | It's an amenity, though. | ausbah wrote: | lists of advice like this from experienced practicioners are | always great, but does anyone have any good methods for actually | incorporating just pieces of wisdom into their own work? I find | myself bookmarking stuff like this but never coming back to it or | unsure how to fully utilize them | rzimmerman wrote: | These lists can be fun because they're a list of inside jokes, | but there's nothing useful or actionable here. I'm not a fan of | this type of self-congratulating stuff about budgets and | schedules never being right and launch vehicles being too hard. | This type of mentality is why most of the industry is stuck in | the 60s. Honestly it sounds analogous to wondering why anyone | would want a personal computer 40 years ago. ___________________________________________________________________ (page generated 2021-01-09 23:01 UTC)