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Murphy's Law Rules NASA
3x37 writes "James Oberg, former long-time NASA operations employee, now journalist, wrote an MSNBC article about the reality of Murphy's Law at NASA. Interesting that the incident that sparked Murphy's Law over 50 years ago had a nearly identical cause as the Genesis probe failure. The conclusion: Human error is an inevitable input to any complex endeavor. Either you manage and design around it or fail. NASA management still often chooses the latter."
Except, of course, that we programmed the machines in the first place.
When a computer program crashes it's usually down to the human(s) who programmed it, and in the rare occasions it's a hardware glitch and it was humans who designed the hardware, so we're still to blame either directly or indirectly.
I suppose it's like the argument about whether bullets kill or the human who pulled the gun's trigger.
Sorry, but my karma just ran over your dogma.
Then I remember Apollo 1, that killed 3 astronauts, and Apollo 13, that nearly killed 3 more.
To invoke Heinlien, Space is a harsh mistress.
To invoke Sun Tsu, success in defense is not based on the likelyhood of your enemy attacking. It is based on your position being completely unassailable.
"Learning is not compulsory... neither is survival."
--Dr.W.Edwards Deming
``Human error is an inevitable input to any complex endeavor. Either you manage and design around it or fail.''
This is a very good point, and I wish more people would realize it.
For software development, the application is: Just because you can write 200 lines of correct code does not mean you can write 2 * 200 lines of correct code. Always have someone verify your code (not yourself, because you read over your errors without noticing them).
Please correct me if I got my facts wrong.
>>Either you manage and design around it or fail. >>NASA management still often chooses the latter.
This is hindsite at its best, and is the classic comment by beareaucrats who have no concept of what cutting edge design is about. F1 race cars, Racing Sailboats, Nuclear Reactors - NO design is failsafe, and NO design is foolproof. Especially a one off design that isn't mass produced. Even mass produced designs have errors, like in the Auto Industry. It is a simple fact of life that engineers and managers balance Cost and Safety constantly.
What you SHOULD be comparing this against is other space agencies that launch a similar number of missions and sattelites - i.e. other real world examples.
Expecting perfection is not realistic.
If you compare the advances to Science and Knowledge due to mistakes rather than deliberate acts, it might come out that everything is a mistake.
Recently I took a class on AI (insemination, not intelligence) and apparently the two biggest breakthroughs by Dr. Polge, in preserving semen were due to mistakes. First, his lab mislabeled glycerol as fructose and they were able to find a good medium for suspension. Secondly, he blew off finishing freezing semen to go get a few pints and didn't make it back to the lab until the next day thus discovering that it was actually better to not freeze the stuff right away.
Mistakes are some of the best parts of science and life in general. It's best to try to make more mistakes (i.e. take risks) than it is to try and always be right. (unless you are obsessive compulsive).
Then you double check the checkers, and so on... that's the point of the article... humans will err... Like Demming said... "you can't inspect quality into a process."
I think the biggest difficulty surrounding large organizations is the lack of communication tools linking the right engineers together. It seems unfathomable that some of these mistakes were able to propegate throughout the entire engineering process and nobody caught them.
Unless you consider the fact that often in large organizations, the left hand typically has no clue what the right hand is doing. I work at Lockheed Martin, and typically I'm involved in situations where one group makes an improvement that then none of the other groups know about, changes/decisions are poorly documented (if at all) so nobody knows where the process is going, people making poor decisions due to lack of proper procedures from management about what to do, teams not being co-located, poor information about which people have the necessary knowledge to solve a particular problem, or any number of things that confuses the engineering process, to the detriment of the product. Most of these situations are caused by a lack of communication throughout the organization as a whole.
This is a serious problem, and it needs to be acknowledged by the people in a position to make a difference.
Now suppose this output is double-checked by another engineer, who also has a 5% chance of error. 95% of the first engineer's errors will be caught, but that still leaves a .25% chance of an error getting through both engineers.
No matter what the percentages, no matter how many eyes are involved, the only way to guarantee perfection is to have someone with a zero percent chance of error...and the chances of that happening are zero percent. Any other numbers mean that mistakes will occur. Period.
I remember reading a story somewhere about a commercial jet liner that took off with almost no fuel. There are plenty of people whose job it is to check that every plane has fuel...but each of them has a probability of forgetting. Chain enough "I forgots" together, and you have a plane taking off without gas. At the level of complexity we're dealing with in our attempts to throw darts at objects xE7 kilometers away, it is guaranteed that mistakes will propagate all the way through the process.
Reality has a conservative bias: it conserves mass, energy, momentum...
I love how journalists and others like to sit back and criticize these engineers' efforts. They are human, and they will do stupid things. Having been trained as a mechanical engineer (although I mostly do software engineering now), I have some idea of how many calculations have to be made to design even one aspect of a project. I couldn't imagine the complexity of such a system, trying to account for every scenario, making sure agorithms and processes work as planned for ONE mission. No second chances. That we have individuals willing to dedicate the mental efforts to this cause at all is worthy of praise. These people have pride and passion in what they do, and I'm sure they will continue to do their best.
For anyone wanting to yack about poor performance... put your money where your mouth is. I just get sick of all the constant nagging.
this is my sig, be amazed.
Second, the stable of competent contractors that existed in the 1940-1960 time frame is gone. North American, Grumman, McDonnell, dozens of others that could be named have been absorbed into 2-3 borg-like entities. The result is less competition, less choice, less innovation, few places for maverick employees to go, and in the end worse results from outsourcing.
sPh