NASA Will Man Destruct Switch Just In Case
Ant writes "Popular Mechanics reports if the looming Discovery mission or any other between now and the spacecraft's retirement loses control, National Aeronautics and Space Administration (NASA) is prepared to ditch it in the Atlantic ocean — or blow it up. The article also shows complete no-fly-zone maps and a photograph of the switch."
This is such a non-story. NASA has a Range Safety Officer for every single launch, manned or not, and always has.
Give a man fire, and you warm him for the night. Set a man on fire, and you warm him for the rest of his life.
The "Test" button probably checks the detonation circuits, WITHOUT igniting the actual charges. And the "Safe" button is probably for permanently disarming the charges once the shuttle's in orbit.
Yes, they are. They always have. *Every* NASA rocket launch includes a self-destruct to prevent ground casualties. This includes the manned missions. In such cases where it would be used, the crew is either dead or will unavoidably be dead very shortly, and the lives on the ground must be saved.
When our name is on the back of your car, we're behind you all the way!
And if you need an example of why those destruct systems are required, watch this.
I've met at least one of the Range Safety Officers while working out at Cape Canaveral. It's not something they like to talk about much, when it comes to the Shuttle.
The Solid Rocket Boosters can't be stopped once they are started, but they have their own navigation system (rate gyro assemblies, and inertial measurement units) that are considered as/more reliable as those on the orbiter due to the rigidity of the SRBs. So the reason this "self destruct" button exists is because there is no "off" button for the SRBs, but, as far as I know, it is only an issue if its quad-redundant navigation system fails and somehow its thrust gets stuck in an unsafe vector, and that is very unlikely.
More detail, including why you can't jettison the flight deck with all the crewmembers: http://en.wikipedia.org/wiki/Space_Shuttle_abort_modes
For the technical details on how this works, check out an old Risks article here. They put a lot of thought into the system.