vimānāgryeṣu putrakāḥ

tada-then; vikuntha-of the Supreme Lord; dhisanat-from the abode; tayoh-as both of them; nipatamanayoh-were falling; haha-karah-roaring in disappointment; mahan-great; asit-occurred; vimana-agryesu-in the best of airplanes; putrakah-O demigods.