I am heading on a TPAC flight here in a couple weeks and I am certainly changing into my public sleeping attire (gym shorts and a tshirt) for the 8 hours or so I plan on sleeping. No sense in being uncomfortable for 12+ hours.

Europe I just usually wear a nice pair of tennis pants which are breatheable with a nice polo just to stay comfortable for the longer european flights, and just my jeans and a sport coat for the shorter european hauls.

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