How much weight can an Aarakocra carry when flying?

(related to Prison break with an Aarakocra)

The title pretty much says it all. Are the rules for flying creatures the same as for anyone else, using the Strength * 15 = weight in pounds formula ?

Some additional information about the Aarakocra’s own weight (from the PotA Player’s Companion):

Size. Aarakocra are about 5 feet tall. They have thin, lightweight bodies that weigh between 80 and 100 pounds. Your size is Medium.

With a Strength of 10, the Aarakocra should be able to carry 150 pounds, which is already a lot, even without flying.