ReformedCharacter wrote:ukmtk wrote:Maybe future lunar landers need to have a "this way up" on the side just so people can tell which way it is oriented?
Despite clear instructions, that didn't prevent a technician installing accelerometers upside down on a Russian Proton-M - which crashed as a consequence:...a report from Russian Space Web says investigators have traced the problem to a series of sensors that were apparently installed upside down.
The so-called angular velocity sensors (дачик угловой скорости in Russian, according to NPR's Moscow bureau) were a critical part of the circuitry that kept the rocket upright during launch. They were so important, says Russian Space Web, that they even had little arrows on them that were supposed to point toward the top of the rocket.
Quite a spectacular video here:
https://www.npr.org/sections/thetwo-way/2013/07/10/200775748/report-upside-down-sensors-toppled-russian-rocket
RC
I once listened to an air investigator describing a plane crash. From the wreckage they found that someone had ground off the guide pins on a fuel valve that prevented incorrect orientation allowing the valve to be put in the wrong way.
Someone once said that fools are ingenious as in this case, but in many cases it is designs that do not make incorrect orientation impossible without tampering with the device. Recently I blew up a cnc mill controller by mistakenly connecting a male barrel connector to the wrong female receptacle. After that I taped up the wrong receptacle on the new board but my inattention & ease of screwing up cost me over a week & money to recover from. Sometimes troubles come very unexpectedly due to events beyond control. Last week I got a mains shock thanks to something (mouse?) having broken the insulation on a mains cable leaving bare copper exposed that had oxidized to be difficult to see against the black pvc cable. It always makes sense to eye over things before & during use & where possible have check lists to ensure things are not forgotten.
Regards,