By arriving... by when?

By the time forwarded to the tower.

So, if inaction (not arriving) is the cause, then the proximate cause
must be something like a timer going off.

Why?


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

The tower is sent an "expect arrival at 5:34". At 5:36 the plane arrives.
What is different about the two minutes after 5:34 compared to the two minutes
before 5:34? Just that at 5:34, 5:34 happened, and that is special because it
is an expected arrival time that was not consummated.

So, at least in somebody's mind, an alarm went off at 5:34. No? Otherwise
there is nothing special about the two minutes afterwards, and no search would
be initiated.

That is, unless what you mean is that a search begins any time a handoff fails
under IFR. This is another reasonable interpretation, when "handoff" is
expanded to include "expected position report". But then, each ETA (EPRT)
would function as the "alarm" I am talking about... getting reset every time.

Is this pretty much the way it happens?

Jose

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