Yep, even if the plane has not landed yet. "If a baby with foreign parents is born on a plane flying above the United States, the baby is automatically granted

Yep, even if the plane has not landed yet. "If a baby with foreign parents is born on a plane flying above the United States, the baby is automatically granted American citizenship. However, if the baby is born while flying over the ocean, its nationality depends on the country from which the plane is registered."