When asked what had inspired this epic, twenty-six and a half minute track, vocalist Phil Mogg replied with one word: "Acid". That may have been the case, but in the three decades and more that followed its release, it is doubtful if UFO have recorded anything quite as awesome. Mick Bolton left the band in January 1972 being replaced (eventually) by the youthful Michael Schenker
. The Schenker years are generally regarded as UFO's finest, but anyone who has heard "Flying" in its entirety will realize what a hard act the German fretboard wizard had to follow.