<< It probably is possible to hit something with a rocket, given enough tries.
But would it be the way the terrorists actually WOULD do it? Would they go try
to buy commercial motors, thus needing goverment permits and hobby
certification? Of course not. They could mix their own motors, or much more
likely yet they could just buy missiles on the black market. >>
Heck, why even bother with missiles at all, when they could simply use a
hunting rifle? It would certainly be far cheaper, easier, more accurate and
more effective than using hobby rockets. And if for some reason they were too
dumb to use a gun, there are plenty of other creative ways to bring down a
plane -- air cannon (pumpkin-sized), release a few hundred mylar balloons (or
doves) from a truck under the takeoff path, etc.