All of my west to east flights were night flights, and the DCs I took with me slept after a while. Going back east to west was less easy as it is daylight all the way and lots of constant noise fro mother passengers.
The airline provided a cardboard bassinet for small lap ticket DCs to sleep in but they ended up on my lap as there was nothing but a folded up airline blanket by way of padding and it was all a bit strange for them.
Calgary to London is usually about 8.5 hours. Factor in about two hours before dinner service is over and another hour for people to settle down and stop going to the bathroom and you are really not looking at much quiet time. People have an insane tendency to get up at the crack of stupid o'clock on transatlantic flights too, and chat together, go to the loo, open up the shutters to see if there's land below, so the DC may be disturbed in the morning.
The worst part is getting to the loo yourself, though trying to eat your airline meal with a 10 month old to hold and keep out of your food may come a close second. Ask for help from the flight attendants. or other passengers who seem nice. Bring a selection of quiet toys your DC likes -- board books, etc. and a few little new ones is a good idea. Let the baby shred the inflight mag if nothing else seems to be working.
Dress the baby in PJs or clothes that are comfy to sleep in and of course something that is easy for changing nappies in. Bring more nappies than you think you need. If formula fed, bring ready made and lots of bottles. Staff normally will not warm bottles for you. Dress yourself in clothes you can pull down and up again using one hand.
A bulkhead seat can be nice but not if it's close to the loo. There will be people and conversation at the loo door all night and you will be disturbed by the sound of it banging shut.
If breastfeeding, cast aside your nervousness and Just Do It.