Flight towards London

Harry did not think he had ever moved so fast: the Thestral streaked over the castle, its wide wings hardly beating; the cooling air was slapping Harry's face; eyes crewed against the rushing wind, he looked round and saw his five fellows soaring along behind him, each of them bent as low as possible into the neck of their Thestral to protect themselves from his slipstream.
(OotP, UK edition, p. 675)