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Akin's Laws of Spacecraft Design


pander59

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Granted, these humorous items were actually meant for real spacecraft design, but I don't see why the comments do not cater to even our own machinations in such a simulated environment. I know I immediately thought of the community the minute these came back into my vision.

Enjoy.

Akin's Laws of Spacecraft Design*

1. Engineering is done with numbers. Analysis without numbers is only an opinion.

2. To design a spacecraft right takes an infinite amount of effort. This is why it's a good idea to design them to operate when some things are wrong .

3. Design is an iterative process. The necessary number of iterations is one more than the number you have currently done. This is true at any point in time.

4. Your best design efforts will inevitably wind up being useless in the final design. Learn to live with the disappointment.

5. (Miller's Law) Three points determine a curve.

6. (Mar's Law) Everything is linear if plotted log-log with a fat magic marker.

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.

8. In nature, the optimum is almost always in the middle somewhere. Distrust assertions that the optimum is at an extreme point.

9. Not having all the information you need is never a satisfactory excuse for not starting the analysis.

10. When in doubt, estimate. In an emergency, guess. But be sure to go back and clean up the mess when the real numbers come along.

11. Sometimes, the fastest way to get to the end is to throw everything out and start over.

12. There is never a single right solution. There are always multiple wrong ones, though.

13. Design is based on requirements. There's no justification for designing something one bit "better" than the requirements dictate.

14. (Edison's Law) "Better" is the enemy of "good".

15. (Shea's Law) The ability to improve a design occurs primarily at the interfaces. This is also the prime location for screwing it up.

16. The previous people who did a similar analysis did not have a direct pipeline to the wisdom of the ages. There is therefore no reason to believe their analysis over yours. There is especially no reason to present their analysis as yours.

17. The fact that an analysis appears in print has no relationship to the likelihood of its being correct.

18. Past experience is excellent for providing a reality check. Too much reality can doom an otherwise worthwhile design, though.

19. The odds are greatly against you being immensely smarter than everyone else in the field. If your analysis says your terminal velocity is twice the speed of light, you may have invented warp drive, but the chances are a lot better that you've screwed up.

20. A bad design with a good presentation is doomed eventually. A good design with a bad presentation is doomed immediately.

21. (Larrabee's Law) Half of everything you hear in a classroom is crap. Education is figuring out which half is which.

22. When in doubt, document. (Documentation requirements will reach a maximum shortly after the termination of a program.)

23. The schedule you develop will seem like a complete work of fiction up until the time your customer fires you for not meeting it.

24. It's called a "Work Breakdown Structure" because the Work remaining will grow until you have a Breakdown, unless you enforce some Structure on it.

25. (Bowden's Law) Following a testing failure, it's always possible to refine the analysis to show that you really had negative margins all along.

26. (Montemerlo's Law) Don't do nuthin' dumb.

27. (Varsi's Law) Schedules only move in one direction.

28. (Ranger's Law) There ain't no such thing as a free launch.

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.

30. (von Tiesenhausen's Law of Engineering Design) If you want to have a maximum effect on the design of a new engineering system, learn to draw. Engineers always wind up designing the vehicle to look like the initial artist's concept.

31. (Mo's Law of Evolutionary Development) You can't get to the moon by climbing successively taller trees.

32. (Atkin's Law of Demonstrations) When the hardware is working perfectly, the really important visitors don't show up.

33. Space is a completely unforgiving environment. If you screw up the engineering, somebody dies (and there's no partial credit because most of the analysis was right...)

*I've been involved in spacecraft and space systems design and development for my entire career, including teaching the senior-level capstone spacecraft design course, for ten years at MIT and now at the University of Maryland for more than a decade. These are some bits of wisdom that I have gleaned during that time, some by picking up on the experience of others, but mostly by screwing up myself. I originally wrote these up and handed them out to my senior design class, as a strong hint on how best to survive my design experience. Months later, I get a phone call from a friend in California complimenting me on the Laws, which he saw on a "joke-of-the-day" listserve. Since then, I'm aware of half a dozen sites around the world that present various editions of the Laws, and even one site which has converted them to the Laws of Certified Public Accounting. (Don't ask...) Anyone is welcome to link to these, use them, post them, send me suggestions of additional laws, but I do maintain that this is the canonical set of Akin's Laws...

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19. The odds are greatly against you being immensely smarter than everyone else in the field. If your analysis says your terminal velocity is twice the speed of light, you may have invented warp drive, but the chances are a lot better that you've screwed up.

This. All of this, but especially THIS.

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I like these, nice 1! Some of them really speak to me!

If I may suggest a couple, one from my old boss;

"For every complex problem there is a simple solution....that is usually wrong"

And a rule (from the book "The Mythic Man Month"), that I keep finding to be depressingly true;

From the point at which you have a good working solution, it will take NINE times more work before its production grade ready.

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The best part for me was the reference to these being turned into the laws of accounting. I work for a small municipality where things would be so much better if our city clerk would first realize that she is NOT smarter than everyone else (including our auditors), ala "19. The odds are greatly against you being immensely smarter than everyone else in the field. If your analysis says your terminal velocity is twice the speed of light, you may have invented warp drive, but the chances are a lot better that you've screwed up." She frequently suffers from "24. It's called a "Work Breakdown Structure" because the Work remaining will grow until you have a Breakdown, unless you enforce some Structure on it."and then she fails miserably at "10. When in doubt, estimate. In an emergency, guess. But be sure to go back and clean up the mess when the real numbers come along." I am tempted to print these off and leave them on her desk...

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As to #19.... Back in college, one of my frat brothers was a Aero Engineer. He and his senior lab partner were working on their final project, which was to design an airliner, from scratch. Didn't have to be original in design, just from scratch. They were sitting at lunch one day, audibly grumbling, when asked what was wrong, one of them said "Well we did the math, and apparently there isn't enough fuel on Earth to get this thing off the ground!" At which time the other one yelled, "Wait! I Forgot to carry the 2!".

Side bar:

I ended up as a paramedic for many years. Over that time, I developed a list of my own rules for EMS, some are original, some are stolen:

1) If it's wet and sticky, and not yours, don't touch it.

2) Always try the doorknob first.

3) Have fun, but don't make the News.

4) The ratio of tools on an EMT's belt to their experience is inversely related.

5) When in doubt, add more diesel.

2 and 4 (and for KSP I guess 3 & 5) can easily be applied to this discussion, as in: simplicity first.

Edited by gargamel
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There's another law that KSP players have broken innumerable times:

In order to keep a manned space program safe, economical, and effective, you must do three things:

1) Don't develop any new launch vehicles

2) Don't develop any new launch vehicles

And 3) Whatever you do, Don't develop any new launch vehicles

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The witticisms of engineers and designers always give me a chuckle, particularly given how true they are. I would add a few of my own:

1. Be certain you've learned the right lessons from your mistakes, unless you want to make even bigger mistakes.

2. The plural of anecdote is not data, so test properly instead of going with your gut feeling. Opinions are not acceptable substitutes for facts.

3. The root of any given problem is usually the one thing you're certain you can't change without having to start the whole process over.

4. An idea that works on paper is useless. Get it to work in the real world before you invest heavily in any concept.

5. Experimentation is not a crime, but always have a backup plan for when it doesn't work the way you thought it was going to. And a backup plan for when that one fails, too.

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The witticisms of engineers and designers always give me a chuckle, particularly given how true they are. I would add a few of my own:

4. An idea that works on paper is useless. Get it to work in the real world before you invest heavily in any concept.

I wish teachers and professors adhered to this. I can't tell you how many "Well, I went to Stanford Business school" responses I've heard from people who have zero clue on how a business actually runs.

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14. (Edison's Law) "Better" is the enemy of "good".

I do believe it was Voltaire who said this but he was quote someone as well.

also this one but not sure who to credit it with as it goes back a long way and goes along the lines of...

"Ideas are just the multiplier of implementation"

Good explanation here http://sivers.org/multiply

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23. The schedule you develop will seem like a complete work of fiction up until the time your customer fires you for not meeting it.

24. It's called a "Work Breakdown Structure" because the Work remaining will grow until you have a Breakdown, unless you enforce some Structure on it.

I work in tech support... These two are going on my cubical white board till a manager demands I remove them :P

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My favorite is Augustine's Laws, by Norman Augustine (Yes, same guy running the future-of-spaceflight committees). I prefer the 1982 edition, which was written for military-aerospace engineers, over the one currently in print which is dumbed down and pointed at a more generalist business-layman sort of audience. It's freaking hilarious yet utterly serious at the same time, because every rule is backed up by actual statistics.

3. Law of Apocalyptic Costing: "Ninety percent of the time things will turn out worse than you expect. The other ten percent of the time you had no right to expect so much." (Demonstrates the percentage of programs that overrun their budgets, and produces a formula for determining how much more budget you need to avoid an overrun -- in general, multiply your budget by two and a half).

7. Law of Insatiable Appetites: "The last 10 percent of the performance sought generates one third of the cost and two-thirds of the problems." (This holds for baseball players, optical lenses, airplanes, diamonds and machined parts.)

9. Final Law of Economic Disarmament AKA First Law of Impending Doom: "In the year 2054, the entire [uS] defense budget will purchase just one tactical aircraft. This aircraft will have to be shared by the Air Force and Navy 3 1/2 days each per week except for leap year, when it will be made available to the Marines for the extra day." (When trends for the national budget and the unit cost of aircraft are compared, they eventually intersect. Keep on going and the entire military might of the US, and then the planet will be concentrated into one vehicle by 2200 or so -- this is how we get that Death Star people were asking the White House for.)

10. Law of Undiminished Expectations: "It is very expensive to achieve high degrees of unreliability. It is not uncommon to increase the cost of an item by a factor of ten for each factor of ten degradation accomplished." (The cost of an item is inversely proportional to its reliablity -- the more expensive it is, the quicker it breaks and the longer it takes to repair. This leads to:

11. Augustine-Morrison Law of Unidirectional Flight: "Aircraft flight in the 21st century will always be in a westerly direction, preferably supersonic, to provide the additional hours needed each day to maintain all the broken parts."

Others point out that the trend of adding electronics is so high that eventually there will be no airplane crashes OR takeoffs because the entire aircraft will be electronic. Cost will continue to rise, however, because of the trend of adding software, which is expensive yet weighs nothing. The cheaper and simpler the system, the more testing it requires, and this is directly proportional -- The amount of money spent on one or two spaceflights, after which the craft is declared operational, is pretty close to the thousands and thousands of shoulder-fired rockets that have to be fired before that system is declared operational. Technical manuals and government contracts are getting longer and longer, to the point where the paperwork for some aircraft exceeds their takeoff weight. The weapons that have the greatest impact on the enemy are the simplest and lowest-costing. And so on.

Not to mention that the more expensive the overall vehicle, the cheaper the element at the initial point of failure -- like the anti-radiation missile that kept going off course when a tiny warning sticker was peeled off by the windshear and fell into the radar fuse. Naturally, this was not noticed during testing, but only after a great many of them had failed in combat -- because combat conditions are usually far worse than those they are tested under...

Edited by JenBurdoo
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Some more from my KSP experience and/or medical career:

Medical:

1) It ain't broke, don't touch it.

2) If it ain't broke, but it's in an inconvenient place, don't touch it and move to a place where nothing is getting in the way.

3) If you positively need to touch it, use all protective equipment available and make sure not to screw up.

4) (a quote by my university professor): It is there for a reason. If you take it out, do it quickly when the owner is not looking and put it back ASAP, or replace it with a better version.

KSP:

5) If you are tempted to touch it so hard that you can't resist... you were warned.

6) When in doubt, apply boosters.

7) Logic is the best way to confirm your errors.

8) Laziness is the source of 9 good inventions out of 10 (actual Murphy's science law)

9) If you fail for no reason, google.

10) When things are going well, you obviously forgot something...

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