Originally Posted by
ralfp
Note that US-HND flights do not follow the pattern. There are midnight US departures arriving into HND at 5am or so, as well as ~6pm US departures that arrive around midnight.
Why the difference? I can think of two reasons: lack of curfew and the higher rate of O/D traffic (non-connecting passengers).
Note that you can include both NRT and HND in a search by using TYO (NYC for JFK, LGA, & EWR; WAS for IAD, DCA, & BWI; LON; SEL; etc.)
As others have pointed out, the real reason is that long haul flights to/from HND are only permitted to operate between midnight and 6a.