To give meaning to the part that says "by the time forwarded to
the tower".


Explain.

Rather than explain, let me ask how a search is begun for an aircraft that does
not land when it is expected to. Say you hand off to the tower, and the
aircraft does not contact the tower. The plane is below radar. A few minutes
go by, then a few more, and still no contact. Perhaps the airplane has been
abudcted by aliens, or has crashed in the forest, or has had an electrical
failure, or the nut behind the yoke came off. So, what happens? When?
Triggered by what? Why?

Same question, nontowered.

Jose

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