Akin's Laws of Spacecraft Design
Akin's Laws of Spacecraft Design


 
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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. (Patton's Law of Program Planning) A good plan violently 
  executed now is better than a perfect plan next week.
34. (Roosevelt's Law of Task Planning) Do what you can, where 
  you are, with what you have.
35. (de Saint-Exupery's Law of Design) A designer knows that 
  they have achieved perfection not when there is nothing left to add, but when there 
  is nothing left to take away.
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. 
37. (Henshaw's Law) One key to success in a mission is establishing 
  clear lines of blame. 
38. Capabilities drive requirements, regardless of what the 
  systems engineering textbooks say.
39. Any exploration program which "just happens" to include a new launch vehicle is, de facto, a launch vehicle program.
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.
40. (McBryan's Law) You can't make it better until you make it work.
41. There's never enough time to do it right, but somehow, there's always enough time to do it over.
42. If there's not a flight program, there's no money.
      If there is a flight program, there's no time.
43. You really understand something the third time you see it (or the first time you teach it.)
44. (Lachance's Law) "Plenty of time" becomes "not enough time" in a very short time.
45. 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...)

Me and a reduced set of Akin's Laws, framed on the wall
of the NASA Mission Management Room in Building 30
(Mission Control) at the NASA Johnson Space Center
*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 three decades. 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 (without attribution, of course) 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...  


