Newark in an E-Jet is the most likely somewhat on that list. Edmonton has a direct flight and in 2012 trips between the city pair was 53,265 versus Winnipeg's 34,082. Winnipeg is much closer to a major American hub though where economies of scale can cut out the profit of a direct.
When Icelandair starts receiving its 737Maxs, I could see that. I am not sure Winnipeg could support a wide body service to Europe, especially with the airframe crunch currently going on. The yield would have to be better than an extra frequency from points further west.
Let Icelandair build a market for awhile, then KLM or Air Canada can swoop in and capture that traffic with a direct to Frankfurt or Amsterdam.
HNL will be a challenge. There would have to be a distinct advantage for the airlines instead of connecting through the western three. Maybe Rouge will have enough metal. Winnipeg had a total of 26,284 travelers to and from Hawaii in 2012. Calgary had 178,899, Edmonton 111,100, Vancouver 337,740, and Toronto 106,314. Kelowna had nearly as many trips as Winnipeg at 24,334. Saskatchewan's total is more than Winnipeg's. Victoria's is higher too.
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