It is true that most airlines operate larger, longer-range aircraft on transpacific routes. But Air Canada did operate the Vancouver-Seoul route with a 767-300ER and Canadian still operates the Vancouver-Beijing route with a 767-300ER (5300 miles). Air Canada's longest 767 flight is Toronto-Tel Aviv (5800 miles), but St. Louis-Tokyo would be close to 6400 miles. Would the 767 suffice?
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