I'm flying on sunday, and my plan is to bring an empty bottle on board and fill it with water from the bathroom sink.
I'll make sure to let the flight attendent know before I do it, so they don't think I brought the water on board with me.
My hope is that when I tell her what I am doing, she'll give me a water from the drink tray before the plane takes off.
Can't you just ask for water when you get on the plane?
I have never been refused a glass of water when asked for. May have to wait until everyone gets seated but will probably get it before the door shuts.
I would also recommend not drinking the water from the airplane's sink.