I agree with Traveller book a hotel for a sleep before you drive
In March neither of us slept on the flight I find it impossible, we then had to drive from Manchester to the Borders a 4 hour drive even though we shared the driving it was horrible (and stupid) my husband almost fell asleep at the wheel
We are going again in November but for the first time ever we have decided to fly EDI -LGW - MCO as it's only a 45 min drive from Edinburgh to home
It's dangerous to drive when you are so tired - it scared the s**t out of me although we have done it many times before and have stopped at the services for a short nap - never again
Anyway to answer your question meg I have never found anything that helps me sleep on a flight, I find it too noisy there's always someone talking or babies crying etc plus it's downright uncomfortable
Fly upper class that might do it lol