You can of course fly direct from London to Fort Lauderdale on a Norwegian 787, but you need to start your journey at Gatwick LGW:

https://www.norwegian.com/uk/booking...auderdaleMiami



But as BA is beginning to use its A380 exLHR Heathrow to MIA, you may as well do that as Norwegian isn't great value, or even daily, so any delays can snowball and the drive to Lauderdale is easy-peasy.

You should be able to get an exDUB Club World Business Class fare for around £1,000 rtn, though several exLHR for £1,398 in the current sale:

http://www.britishairways.com/travel...HR&numNights=7