Yes, I know, I wasn't being seious

If fuel efficiency and reduced CO2 ems are the primary requiment then I suspect the aircraft in question will likely be the smaller and larger versions of the a350 which is reportedly better than the 787 in both respects. TG seems to have a preference for airbus of late so I doubt it'll be 777s or any other Boeing unless they are in a hurry with their procument and/or are sourcing 777s from Jet/Gulf as discussed elswhere. Personally, I'd love to see some new 747s (with updated products) as it is still a beautiful airplane both to look at and fly in.