Originally Posted by
QueenOfCoach
As far as I know, it has to do with the density of the air. Warm air is less dense than cold air, thus, heavy objects (such as airplanes) are not as well supported in warmer air.
I invite correction. I am not an aeronautical engineer, but I recollect hearing about that when flying to South Africa during the summer. Take-offs and landings were bunched in the cooler mornings and evenings.
Correct, which is why you see so many very late night and morning departures in Middle Eastern countries. Also, Google 'Hainan Airways Las Vegas' and you'll see they adjusted their flight schedule for the very same reason.