I’ve been following the space program for many years since childhood, but there’s one small question that I’ve never really been able to find a good answer for. Maybe some of our aerospace oriented Dopers can help.
At each launch of a rocket, manned or unmanned, there is a person or office know as the RSO or Range Safety Officer. The purpose of this office being to protect the people and installations on the ground from damage, destruction and death caused by an errant rocket going off course, etc and impacting a populated area, etc. This is done by initiaiting a destruct command to detonate the booster and fragment the vehicle so that the smaller pieces will do less damage.
So here’s the question - are the RSO’s protocols different for a manned mission than for an unmanned one? I mean it’s one thing to “push the button” and blow up a Delta carrying a satellite. It’s quite another to have to destroy a vehicle carrying people.
I’ve been assuming all this time that the RSO would wait until the last possible gasp and be very, very assured that there was no possibility of survival for the crew before initiating booster destruct on a manned mission, while perhaps having a “looser” set of criteria for an unmanned one - am I wrong?
I always thought that the positioning of the pads on the swampy parts of the eastern Florida peninsula and launching out over the Atlantic solved the problem of “the rocket is heading for the school – blow it up” so that you wouldn’t need something or someone like that. I was at KSC a few months ago for a launch (109,Columbia) and I was impressed at how isolated the pads are from the population.
Correct - right up until a rocket booster’s guidance system malfunctions and begins to steer back to the west. Once the guidance system is compromised, a rocket can become like a toy baloon that’s released to go wherever it wants.
All of NASA’s rockets still have destruct systems, even though they take off from water.
The older rockets for the Apollo project has escape rockets attached to the crew capsule. In an emergency, explosive bolts seperate the capsule from the rest of the rocket, the escape rocket pulls the capsule safely away, and the destruct charges blow the launch rocket to bits.
The Shuttle has destruct charges on the external tank and the solid-fuel boosters. The orbiter itself does not have destruct charges. It is not at all likely that the destruct system would ever be used while the orbiter is still intact - NASA has various contingency plans to handle things like SSME failure in which the shuttle makes an emergency landing after seperating from the boosters. A malfunction that would require destroying the shuttle stack before booster seperation would probably have already doomed the crew anyway, as in the Challenger launch explosion.
The SRB from Challenger were destroyed after the explosion for that very reason, they were becoming wildly unpredictable and thought it best to destroy them.
On hindsight, I’m sure they would have loved to have looked at the complete SRB (since one is what caused the accident) but safety at the time dictated they destroy them.
My guess is that if a rocket or shuttle were somehow knocked off course so that it threatened a populated area, it would be destroyed whether or not people were on board.
However, rocket and shuttle trajectories are mapped so they don’t pass over populated areas. Columbia’s debris field covers at least a thousand square miles (probably more) yet there were no casualties on the ground nor significant reports of property damage.
I’m not talking about Columbia. That was a unique circumstance and does not reflect the failure of a launch booster at launch.
As you said at first, the rocket WILL be destroyed if it flies off course. Rockets have been known to fail to the extent that their launch trajectory turns toward land and populated areas. Just because the launch is MAPPED to go out over the ocean or over unpopulated areas doesn’t mean that the rocket will actually DO that. Thus the need for the RSO.
The RSO will command a destruct, that is understood here. Manned or unmanned - that is also understood.
What I’m trying to nail down is whether the decision protocols differ between a manned and unmanned mission. I can’t image the same set of criteria being applied to a manned launch that would be applied to an unmanned one - thinking of timing, verification of trajectory, etc - but I may be thinking to emotionally on that.
I’ve read of early launch terminations by range safety after only a couple of seconds of bad trajectory data on Delta flights carrying satellite payloads - in other words, trajectory shows “bad” RSO destruct command is issued very quickly, with very little second-guessing, verification, etc. Computers say “off course” RSO says “boom.”
I guess what I’m trying to find out is whether pure engineering is at work if the RSO ever has to terminate a manned launch or whether the human factor is taken in to account. Ground based damage and destruction would be just as bad with a manned booster failure or an unmanned one, so would the prevention of thousands of deaths be justified against the loss of a few if a manned launch had to be terminated by range safety?
Two days of searching and I’ve come up with very little. Could be that this is something NASA doesn’t want to talk about too - or that nobody has written about before.