Can birds sleep while flying?

In the study published in the journal Nature Communications, scientists fitted frigate birds with devices that monitor the electrical activity in their brains and monitor their head movements. The data show that frigate birds sleep an average of 41 minutes a day while flying. This period is much shorter than their sleep on land. Because frigate birds sleep an average of 12 hours a day while on land. In addition, frigate birds do not sleep uninterruptedly while flying, their sleep in the air in the form of short sleeps.