So, it has been a recurring sound design question/challenge I've quite often come back to. Today I can say I'm the closest I've ever been from creating this sound using noise and plugins.
I run pink noise through the AIR Frequency Shifter plugin that comes with PT8. In Up & Down mode (the third position of the selector), with a feedback between 70 and 100% and mixing the output between 50 and 100% I managed to get the base with a frequency between 5 and 10Hz. Then, using flanger I added some "turbulence" to it (haven't managed to get an actual flutter yet) and finally some AIR Enhancer to generate some whistling highs and accentuate the cyclical thump.
Have you guys ever tried this? Would you like to share your experiences here? Any techniques/plugins that might give me a better result? The AIR Filter Gate plugin has Attack, Hold and Release controls that gave me superb control over the character of the propeller, but then it only has a stepped rate so you can't vary the modulation speed (I haven't tried automating the tempo of the session that is).