"A user fee system can generate sufficient funds during the
good times, but it falls apart during an economic downturn, which
is exactly what happened to NAV CANADA after 9/11. The US national
air transportation system is well served by the stable funding
stream provided by the existing combination of taxes and general
fund contributions."
Source: AOPA VP of Regulatory Affairs Andy
Cebula, on privatized ATC operator NAV CANADA's proposal to add a
$5-per-day fee for aircraft less than 6,075 lbs gross weight to
operate at any of eight major Canadian airports.