Cleared to Land

It must be about 10 minutes before official
sunrise, and the pilot knows that the plane
has less than 45 minutes of fuel remaining
-- but more than 40 minutes, of course.

epicted on the right is something that no pilot ever wants to see on his or her instrument panel while aloft. Meanwhile, here in the solution to this puzzle is evidence of the dilemma faced by regulators intent upon improving public safety -- while being opposed in that effort by a public reluctant to be regulated.

In the awkward, two-rule compromise set forth in the puzzle's hint, the sophisticated reader will see the outlines of a bygone debate and might well inquire: What real sacrifice in flying convenience results from having one simple rule?

"The pilot must plan and execute his or her flight so as to assure at least 45 minutes of fuel remaining upon landing [day or night]."

Try to imagine a sudden, deafening silence in the cockpit when that noisy contraption up front stops swinging those paddles around and hearing these words spoken by the pilot...

"Oops, I thought I had another twelve minutes of flying time!"

Few VFR pilots, truth be known, keep track of their fuel remaining with all that much precision. Safe flyers generally elect to 'ferry fuel' -- carry extra gasoline -- so they don't have to worry about the subject aloft.