682ft AMSL, an excellent post there.
I seem to remember a poster some time ago, cannot find it now though so sorry for pinching the info, suggesting that something like 85,000 passengers fly to New York ex Yorkshire (or West Yorkshire) and i think that was from MAN. The problem was that of those only a relatively modest percentage were business/ higher fare paying pax. I am aware that freight is important to these longer-haul services for yields unless i can be corrected.
I believe therefore that there is certainly a market from an NY service, though it is not as clear as the PIA services, an that LBA is the only airport in Yorkshire likely to achieve such a route. Perhaps a service to Dubai also?