Porter Airlines Inc. will still dominate airspace at Toronto City Centre Airport in 2010 and well beyond, according to Community Air, a residents group that opposes the terminal's expansion. Even if the Toronto Port Authority, which oversees the island airport, breaks up Porter's monopoly, there are a limited number of slots available, Community Air said in a submission yesterday to the U.S. Department of Transportation. The citizens group noted that Porter will have 120 daily slots - takeoffs and landings - next April, leaving only 47 slots at most available to rivals such as Air Canada Jazz. Community Air made its filing in response to the U.S. regulator's request for any objections to tentative approval granted to Porter for a foreign air carrier permit. It will "not be in the public interest" to restrict access to the Toronto airport, with Porter having the lion's share of slots, said Community Air chairman Brian Iler. Privately owned Porter is looking to order more planes, so it will be among the carriers vying for the remaining slots.