I have spent a lot of time on planes, in fact, I have flown around the world 13 times. There are times where you need to relax and think less to sleep on the flight or reach near meditative states to pass the many hours in airport lounges.
I have found that modern Classical music produced in the mid 20th century is a perfect sonic accompaniment for these long journeys. The first piece of minimalistic modern classical I discovered was 'Music for 18 Musicians' composed by Steve Reich. I was given the CD by a friend on my birthday present; he knew that the arpeggiated rhythms would appeal to my obsessive nature and the and the harmonic movements called Pulses would allow me to explore my the cathedral of the mind.
These mixes contain some of the best minimalistic Modern Classical music I have discovered to date, from artists like Philip Glass, Brian Eno and Edmund Niemann. I don't think I have even scraped the surface of this musical genre, so will keep exploring and advise you to as well.