There is an easier way around all that...
First: open your core/app.config.php
Second: find this...
# Pilot pilots to only fly aircraft they're ranked to
Config::Set('RESTRICT_AIRCRAFT_RANKS', false);
Make this true.
Third: copy and paste that code in your core/local.config.php file so it doesn't get overwritten during any updates to phpVMS.
Fourth: change all your aircraft to the rank you want each of them to be flown by. Now when a member searches for a flight, only those routes that have the aircraft they are ranked for will show up in the results page.
Note: All aircraft at and below their rank will show, not the ones that they aren't ranked for.