Frode Berg wrote:

No one has "scanned" him at the grass strip, and thus he is not "clean". He
could be carrying a s***load of explosives on board and tax over to the
commercial planes, right?
Doeas he have to stop at the taxiway and be "checked" out by security before
taxiing to the hangar?

Do you have any rules for these sort of things in the US or other parts?

Some. There are no rules for scanning people loading and departing from private
strips, and few (if any) rules at what we call uncontrolled airports. But you
can't land a light plane at a commercial airport and just taxi up where the
commercial planes are. At some airports (like Shenandoah Valley Regional in
Virginia), there's a line on the pavement. You stay on one side and the
commercial guys are on the other. You could get as close as perhaps 30 meters
before someone yells at you. On one hand, a suicide pilot could cross that line
and travel that 30 meters before anyone could stop him. On the other hand, the
commercial flights out of SHD carry only perhaps 15 passengers.

At a larger airport (such as Knoxville, Tennessee), the closest you could get
without the controller complaining would be more like 200 meters. It's much more
likely that someone on the ground could do something to stop you if you tried to
taxi into an airliner there.

At a major airport (such as Atlanta or Newark), there's no way you'd be able to
get anywhere near the commercial planes.

George Patterson
If a tank is out of ammunition, what you have is a sixty ton portable
radio.