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Probe Crash Due to Misdesigned Deceleration Sensor
squirrelhack writes "Seems as though the Genesis spacecraft was able to launch from earth, travel through space, avoid aliens, and cruise back into the atmosphere to be caught by stunt pilots waiting patiently with their helicopters. Alas, the brakes didn't work because a sensor was designed upside down.
I wish POLITICIANS would stop judging accidents with NASA and spaceflight in general as "wastes".
It's NOT a waste. Research REQUIRES failure. SUCESS requires failure.
One step at a time, my fellow scientists and engineers. One step at a time.
Reply or e-mail; don't vaguely moderate. Ex-O'Reilly/MIT employee, now a full-time Google employee.
Because no matter how much money you spend you can't buy perfect humans, and to err is human.
To correct error is engineering.
Once upon a time some 'wires' in my brain got crossed and I actually picked up a hot soldering iron from the wrong end. Have you ever had that experience where you realize you're about to do something terribly, terribly wrong, but the impulse has already been sent and you can't stop it?
I hate when that happens.
But I only did that once. Pain is a great teacher. One might almost come to the conclusion that that's what it's there for.
So the next probe will have the sensor absolutely correct and working. They'll have to come up with brand new ways to mess things up.
Just like I do.
KFG
Isn't this the same situation that resulted in the creation of Murphy's Law. They were doing acceleration tests on humans but they installed the sensors backwards so the tests were useless.
The original lesson they learned was: That if a design allows for a part to be installed incorrectly, then that part will be installed incorrectly (eventually, or maybe even the first time).
Just a little bit of history repeating.
Sheeeeezzzz...
These kind of mistakes make me wonder. WHY does NASA *HAVE* to re-design every freakin' thing on every freakin' mission from the ground up every freakin' time?
We're flying alpha-test spacecraft.
Re-usable modules anybody?? Heard of those? Standard designs? Sure, some parts are going to be different, namely the actual scientific instruments, but fer ghodssake an accelerometer?! WhyTF do we need to redesign that (its a weight, a spring and a switch, fer the love of pete) ?!!
-sigh-
-- -- The Dragon De Monsyne
But we know things like this already. Failure is fine if you learn from it.
What did we learn? Um... accelerometers only work in one direction... if you install them backwards, things don't happen right!
We tolerate mistakes if we have to make them, but this one (like all the recent Lockheed Martin screwups on work for NASA) appears to be stupidity.
-- IANAEG - I am not an elder god.
Just like you should never write that code that cannot be tested (in the perfect world, every line would be executed during testing), you should never design a subassembly that cannot be tested.
It's a organizational attitude adjustment that's needed to put this into effect.
I remember reading about an Apollo moon car issue where a core-sample clamp would not work because it was installed upside down. It ended up wasting about an hour of astronaut time. Parts designers should avoid symmetrical designs where things fit, or semi-fit, if misoriented. Design them with things sticking out so that it would not fit *at all* if put in wrong.
Table-ized A.I.
I hope not. As the article says, the board was Broken As Designed -- the sensor was installed exactly as specified, but the specification was wrong.
Mind the Gap
besides, we might find a use for it someday. Radioisotopes don't grow on trees...