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NASA Finds Critical Assembly Fault in Shuttle
mzs writes "During corrosion inspection on Discovery, technicians noticed that one of the gears in a rudder actuator had been installed backwards. This particular actuator was the top-most of four that control the air brakes on the tail. As luck turns out, if it had been the bottom-most actuator, loss of the shuttle and crew would have been nearly inevitable. Plans are in place to have four spares by the time Shuttle missions resume next year."
It'd be nice to give some credit for the people that have put in layer upon layer upon layer of safeguards to check for exactly this sort of thing and the dilligent people that find this stuff. And caught it.
Maybe you missed the details, but this has been in place on the Discovery for over 20 years.
-molo
Using your sig line to advertise for friends is lame.
Is anyone else reminded of the story of how Murphy's Law came into being (where something could be connected up the wrong way round and was)? I'm sure NASA has tightened up its procedures since Challenger/Columbia, but given that these things could be fitted either way it was an accident waiting to happen - thankfully it never did.
NASA Finds Hidden Shuttle Danger Same story, different article, in case the posted one gets /.'ed.
The engineers don't assemble the shuttle in space, so that shouldn't be an issue.
!#@%*)anks for hanging up the phone, dear.
I think the reality is more like "Money bullsh*ts".
You will not drink with us, but you would taste our steel? - Walter Matthau, The Pirates
The shuttle is the most complex system ever engineered by people... by orders of magnitude.
It's not suprising that there are flaws in the system - disasters lying dormant until the moment when they cause the destruction of the entire system.
This is one of the biggest arguements for a Vertical Takoff / Vertical Landing vehicle - it simplifies the system because it eliminates specialized components for landing.
Here's the mantra: fault tolerant systems. Things will fail. Can your space shuttle deal with those failures gracefully?
1. 2.
Like all high-tech endeavors, "rocket science" is a blend of many different fields. I happen to think that electrical engineering is far more difficult than aerospace engineering ever could be, but I have helped EE friends with their required mechanical engineering classes, and they got stuck on things I thought were simple and obvious. I'm sure they felt the same way when the time came to help me with my EE requirement. Ditto me and my CS friends. A lot of it is a matter of training and experience.
;)
I'm qualified to work on things like airframes and engines, and I can calculate a pretty mean orbit, if I do say so myself. But I'm lost when it comes to things like avionics or heat shield design. So "rocket science" is indeed complex and tricky, and a successful rocket design will require experts from many fields. But things like compressible flow, which seems to be what Carmack's talking about, aren't really outside the grasp of a dedicated student at all. And of course, all of this sounds like black magic to the nontechnical layman.
Of course, we don't go around telling people this, or we wouldn't be able to look down our noses at everyone else. "I design jet engines, and I've done some work on the Mars program. Oh, you write computer games? Aw, that's cute."
-Carolyn
Like Daddy always said: if you can't dazzle 'em with brilliance, baffle 'em with bullshit.
NASA's best disagrees:
If NASA managers had realized early on that Columbia had suffered a catastrophic breach in its left wing during launch - either by obtaining satellite imagery or, more likely, by having the astronauts stage an inspection spacewalk - they might have had time to mount a repair spacewalk or even an emergency rescue mission with the shuttle Atlantis, the chairman of the Columbia Accident Investigation Board said today. link.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
...I remember as much from "Engine parts" that depending on load, you'd like the teeth of the gear to NOT be symmetric. This would give you better interconnection in one direction (the "right" way) and worse in the other (the "wrong" way).
Ever see a winch? The teeth on the gear there is an extreme of that sort - only designed to pull load in. So it's not done to be mean - it's probably done as to fit the spec.
Kjella
Live today, because you never know what tomorrow brings
Actually, that's exactly what caused a 767 crash a few years back. During maintenance, the wrong connecting rod for a thrust reverser was installed, the rod was too big and was hammered into place to make it "fit". Causing the reverser on one engine to deply in mid air.....