I threw my cents at a discussion forum and mentioned two ways to create a video of a flying helicopter with rotor blades ramaining standstill - both approaches after capturing a video of a flying machine with a normal camera (without variable frame rate recording).
I felt trying! Original video was grabbed from YouTube.
Option 1: Use a transcoder and experiment with different output frame rates until the blades are seen standstill.
Option 2: Use a video editing software, remove many frames so that blades are seen standstill.
Attached are the results. Slight blurring is due to the quality of the original video. Orignal frames were not sharp enough. I could have obtained better results if I used the video of a 5 blade helicopter instead of one with 3.