Joe,

The law of contract imposes on the signatories, the agreement they made until it is amended or terminated.
First, in 1983, they approved only STOL aircraft for use in commercial flights, not the Dash 8. That was the compromise that allowed commercial operations to commence. As you’ll readily agree, the Q400 is not STOL.
Then the three signatories agreed, in 1985, that the Dash 8 could be used for general aviation (i.e. not commercial flights). There is no suggestion that the Q400, an aircraft nearly twice the size and weight as the Dash 8 in existence when that agreement was made, could possibly be considered as Dash 8.
Ask any lawyer – the key is what was in the minds of the signatories when they signed.
And Joe, there’s nothing allowing the ceilings on noise to be averaged. Check the Tripartite Agreement. Given its noise characteristics, as supplied to Transport Canada and ICAO by Bombardier, the Q400 is, by definition, an excessively noisy aircraft and is prohibited from the Island Airport as.
That leaves the Port Authority and Porter with a huge problem: they’ve ducked and ignored the clear prohibitions in the Tripartite agreement all these years.
The constraints are real. Those who value the waterfront, and the communities affected by airport expansion are entitled to have them enforced. Porter and the TPA both were well aware of the risks they took in ignoring them. Sometimes risks actually materialize.
To date, the City of Toronto, the only entity entitled to enforce the Tripartite Agreement, has been too timid to take on the issue.
That may well change. Both George Smitherman and Joe Pantalone have publically promised to enforce the Agreement.
And just today, the City has published a request for proposals for a peer review of the TPA study that concludes that up to 202 slots (landings and take offs) are available. The number of slots is determined by a formula mandated by the Tripartite Agreement. This is something we’ve lobbied for since the TPA’s 212 slot announcement last New Year’s Eve.
If the peer review concludes the number of slots is less, there’ll be a clear case for enforcement of that Tripartite Agreement constraint as well.