Were they Ukrainian planes? I doubt if Russian aircraft are flying to the US right now, due to the current situation. But I could see Ukrainian planes flying here, perhaps to bring refugees here. Or to Canada. Seattle would make sense as a destination, though, from the Eurasian continent. I am reminded of Fort Ross which is a park and historical monument on the Mendocino coast of California. Fort Ross in the past was an Imperial Russian outpost where the Tsar, (yes, its that old) had setup to trade with Native Americans for furs.
If any body is visiting the North Coast (of Calif) as a tourist its an interesting place to see. It dates back to the 19th century and its in quite good shape and well restored to the way it was then. I visited it in around 2006, it seems like it was only yesterday. I took lots of photos, thats probably why my memory of it is fresh.