Matt Whiting wrote:



In the case of the nonradar tower, does the flight just "expire" in the
computer or does the approach controller kill the flight once the
hand-off to tower has been confirmed?


You are thinking it's like a VFR flight plan where somebody has to take
some action to stop SAR from beginning. Nobody is on the clock with an
IFR flight plan.


If the pilot misses the approach
and then pops back to approach, do they have to enter the flight back
into the computer?

No.