Murphy’s lag
19 oktober 2004 | 2 kommentarer
Det är Murphy’s lag igen, på riktigt:
”Investigators may have discovered what caused the Genesis spacecraft to crash into the Utah desert this September. Some crucial switches were installed backwards, because of an error in the instructions. (…)
There were four such switches – two as a backup in case the first two failed. But all of them had been installed backwards. As a result the parachute didn’t open, and the capsule plummeted to Earth.”
nature.com:Flawed drawings caused spacecraft crash (18 okt 2004)
Det var ju precis så det började:
”Major John Paul Stapp, a biophysicist and medical doctor, was his own crash test dummy for harrowing tests of high deceleration stress. He had just exceeded his old record of thirty-one times the force of gravity on the rocket sled, but nobody could say by how much – the gauges hadn’t worked. [Captain Edward] Murphy [Jr, of Edwards Air Base, an engineer] found that a technician had installed each of them backward. He drew this lesson: ’If there’s more than one way to do a job and one of those ways will end in disaster, then somebody will do it that way’.
At a later press conference Stapp referred to ’Murphy’s law’, which he expressed in the classically succint form ’If anything can go wrong, it will.’ ”
Edward Tenner: Why things bite back, New York19661996, s 22
Med utgångspunkt i vad som hände finns det ett enkelt sätt att undgå Murphys lag. Skruvar eller andra komponenter kan utformas oregelbundet, så att de bara kan sättas ihop på ett sätt. Det hade man tydligen glömt.
Kategori: Prylar och teknologi
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2 kommentarer to “Murphy’s lag”
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oktober 19th, 2004 @ 08:57
Fantastisk observation; klassisk hönan-kvalitet!
En annan rymdsond som försvann häromåret missade planeten Mars därför att ingenjörerna trodde att de räknade med U.S. customary units, när det i själva verket var SI-systemet.
oktober 19th, 2004 @ 16:13
Och för er som vill ha formeln för Murphys law kan ni hitta den här: http://www9.sbs.com.au/theworldnews/region.php?id=95941®ion=3