I had never been able to sleep on a flight. I could doze a little, but no deep, restorative sleep. I have just returned from a trip to Ireland where I actually got good sleep both going and returning. I awoke on the way there to find the stewardess had lowered my tray table and put breakfast on it. I sit in an aisle seat and the food service didn’t wake me up. Coming home I actually missed out (again from my aisle seat) on the snack prior to landing. This great sleep was due to a gadget I bought on Amazon that has an eye mask and little pillow that straps to the seat’s headrest. I have seen comments that passengers have been told they couldn’t use it, but I had no issues on American. It does take up a bit more room in my under-the-seat personal item than I like, but is so worth the space to arrive rested. Oh, and my husband said I look goofy in it :)
SARISUN Travel Pillows for Airplanes, Stable Head Support, Travel Essential:
https://www.amazon.com/dp/B0CFV5LZ3R?ref=ppx_yo2ov_dt_b_fed_asin_title&th=1
Yikes, that wouldn't work for me, because I'm not a back sleeper. The one I found that sort of helped me sleep in coach was this one because it is more like sleeping face down.
Of course the BEST sleep I get on an airplane is in a lay flat seat and at my advanced age it is totally worth the price.