What is a flying lap?

Answer 1

A flying lap is a complete lap in qualifications. The driver leaves the pits, which is at a point after the start-finish line so the time does not begin until the driver finishes that lap and passes through the start-finish line. If the driver does not get back into the pits and finishes that lap, then it is a flying lap. Of course after finishing that lap the driver goes back into the pits which is not a flying lap. So out of the 3 laps I have mentioned only the one in the middle is a flying lap, because that is the only one that can be measured.

I think that what the authur of the above means, is:

The driver leaves the pits and does a complete curcuit until he reaches the Start/Finish line. (Lap1)

Without stopping or slowing down, he then completes another curcuit which is timed. (Lap2 - Flying Lap)

Then once again, he completes another curcuit to regain entry to the Pits. (Lap3)