A very long time ago, DL flew nonstop to SVO from JFK, but more recently PMNW and then DL connected to KLM for SVO, at times with a very long connection in AMS. KLM had one or two flights per day, usually with narrow body aircraft but at times there would be a wide body plane on the route. The morning flight was scheduled so that the crew turned around at SVO and flew the same aircraft back, after a couple hours on the ground. For FAs, it was a long day but a way to get lots of hours without being away overnight, so some of them really liked the schedule.