Paul "Semtex" Daley secured his win against "Irish" Brennan Ward with an incredible flying knee to the head at the Bellatore 170 on Saturday Jan 21. If you ever had doubts about the additional power you can get with a flying technique, this knockout will convince you that the extra power is worth the practice. Also, a flying technique can be very confusing to an opponent because he/she won't know where it's intended target is; the tendency is to begin blocking as soon as the opponent starts flying. This typically means that the block will be low, leaving the head open for a clean shot.
In this case, the knee when straight to the temple. A strike to the temple creates a massive shock event to the brain. The brain immediately goes into survival mode, shutting the body down, creating a knock out.
Don't underestimate flying kicks and knees thinking they are just for flash. Practice them to get the technique and execute them regular to in practice to keep your body conditioned to execute them effective.