> Why are small planes even allowed to go anywhere
> near where the President is?
They aren't, but with all the impromptu unscheduled
campaigning being done, unless the pilots check the
NOTAMs for new TFRs just before take-off, they won't
have any idea, until an F16 appears along side.
This is highly unlikely to be a DNC attempt to
heckle from the air. The reports I've seen indicate
that at least one of these planes was close enough
to the rally that ground fire would not have been
surprising.
Would it be practical to incorporate some sort of coded messaging in a broadcast radio (be it FM, weather band, or whatever) that would allow a suitable receiver to indicate whether there were any NOTAMs of interest within some distance of any given airport? I would imagine that for pilots who do almost all of their flying within a very small area it would get very boring to read NOTAMs day after day to find there was nothing worth noting.