Originally Posted by BenjaminNYC
You nailed it. ^
On this route, UA uses 319's, 320's, 757's and three-cabin 763's.
There is a 3-class B-777 as well: UA # 946/947 LAX-IAD-LAX. Last winter it was down to a 2-class plane for a couple of months. This year the schedule sofar has it going year round. It was even a 744 last summer.