I'd wager serious money that if you put that on a sign and surveyed people, at least in the US, they'd all still conclude it is a "New York" to "London" flight.
What's the use of a communication tool, if it doesn't actually communicate anything to real people?
Try Our New York–London Flight Connection.
Or if it was New York:
Try Our New York – London Flight Connection.
Note the additional spaces. Agree on the capitalization though.