Patrick Roddie posted a video and asked me to debunk it. The video shows two large planes flying parallel. Roddie seems to assume that the planes are at the same altitude, and asks "is this legal?" He also helpfully gives the time as "about 12-ish" (which would be PDT, hence about 19:00 UTC) MJ Bournon has already posted two likely planes in a comment on the video: These are a good visual match for the planes in the video, when Roddie zooms in on the upper plane you can see the red Emirates logo under the plane, and the distinctive thick bodied shape of the A380 To the question "is this legal", the simple answer is "yes", and most high altitude commercial air traffic in the US (and most of the world) operates under RVSM, meaning that planes must be separated vertically by a minimum of 1000 feet. It's interesting here that the planes have only a 1,000 foot separation though as in the FAA's procedures for RVSM (page 253), they show that planes flying in opposite directions are interleaved, so plane flying in the same direction should be 2,000 feet apart. However these interleaving guidelines are largely intended for east/west traffic, and breaks down somewhat when traffic is flying to the magnetic north or south, and is especially problematic for planes flying over the north pole region. A plane cannot simply hop 1000 feet up or down as it goes from 179° to 180°. Also you've still got to contend with all the east-west traffic. So basically the "correct" altitude for roughly north/south traffic is whatever ATC tell you, to avoid other traffic. Magnetic North is also not the same as true north. In that region, the magnetic north is about 14°, putting magnetic south at around 194°. At that point both planes were on a track of 188°, just 6° from magnetic south, technically eastbound, so FL380 (38,000) would have been a preferred altitude. And if we look back in time a bit (see attached KML files) we can see that both planes were actually at 38,000 feet a few minutes earlier, however they were 13 miles apart. Before they came together for their approach to SFO, the Emirates A380 climbed 1000 feet to 39,000 feet, and then just after passing Roddies viewpoint in Chiloquin the A340 dropped 1000 to 37,000 feet. So Roddie only saw the planes during that brief period when they were (quite legally) flying 1,000 feet apart (vertically). The Lufthansa plane was probably beginning it's descent during that video.