(editor's note:  There has been a discussion mostly off the blog about the number of slots that the Island Airport can handle and how that will impact on the operations of Porter Airlines.  This is Bob Kotyk's analysis of the issue.)

The number of slots is determined by the NEF contour, according to the Tripartite Agreement.

The number of slots in the past 20 years has varied widely, depending on the source.  The latest definitive statement on the number is Roger Tasse who states in his report that it is 120 slots, not all of which are given over to Porter through its Commercial Carrier Operating Agreement with the port authority.

Transport Canada's current undertaking to determine the NEF contours under the planned increased flight activity will not include helicopter movements.  However, it should according to the Tripartite Agreement.  Section 34 (4) of the Agreement states (4) The actual NEF Contours prepared in accordance with subsection (1) shall include the noise attributable to helicopters for any calendar year during which flight paths were required to be followed for at least half of that year pursuant to Section 35.   Section 35 states that flight paths for helicopters are required if the number of helicopter flights per year exceed 5,000.  According to Transport Canad's publication of StatsCan figures, the 5,000 figure has been exceeded in each of the last five years.

From my own observation, the numbers on the Porter expansion plans don't add up.  A count on Porter's schedule reference shows that 90 slots are used on Mondays with a current fleet of 12 planes.  A Porter news release just today states that 20 planes will be in service by the end of the year.  Do the math: 12 planes are using 90 slots; a maximum of 120 slots is available to all carriers according to Tasse.  By the end of the year, Porter will have eight more planes available for fewer than 30 slots.  Either the last eight planes will be under-utilized or some of them will not fly anywhere near Toronto, which is not an economically viable way to run a regional airport, not working out of one's own hub. 

I will bet the farm that the new NEF contour calculations will come up with more than 120 slots.

Bob