"Steven P. McNicoll" wrote in message
ink.net...
Yet when discussing GA fees, you seem to favor a
marginal-cost assessment:

Of course. That's the fair way to do it. Think about it for a moment.
What portion of the national aviation infrastructure would not exist if GA
did not exist? Whatever it costs to support that portion is GA's fair
share. Now, what portion of the bus or subway system would not exist if
there were no bus or subway riders? All of it, of course!

You're missing my analogy. I'm comparing the use of the aviation
infrastructure by GA to the use of the subway structure by my relatives and
me. If my relatives and I didn't ride the subway, there'd be little
difference to the subway system's needs; if GA didn't use the airspace,
there'd be little difference to the aviation system's needs. (Yes, if
everyone stopped riding the subway--not just the group in
question--there'd be no subway. And similarly, if everyone stopped using
the aviation infrastructure--not just the group in question--there'd be no
aviation infrastructure.)

It's fair for bus or subway riders to all pay the same fare because they
all
pose the same cost on the system. It's not fair to charge GA and air
carriers the same fees because GA poses far smaller costs on the system.

To the extent that GA imposes a smaller cost, I agree it should pay a
smaller share. What I'm disputing is your claim that the marginal cost is
the right measure.

Similarly, if I have five immediate relatives, then it's fair for us to
collectively pay half the daily subway fare than some group that has ten
members. Less resource use, lower fees. But that's not the same concept as
assessing our fare according to the marginal cost of our ridership, which
would have us paying practically nothing. Same principle applies to GA.

--Gary