I have tried using a DeNoiser on the audio file to no avail, but my boss wants the clip filmed inside an airplane while in the air to be able to hear his un mic'ed voice. Maybe there are some magic settings to do in the DeNoiser, or maybe there is another tool I can try. Is it possible to remove the air noise without destroying the audio of the voice?
I was not on the video shoot, so I was not involved in the capturing of the audio. I was told reshooting the shoot is not possible and that I just need to fix it, so PLEASE help me if you can!
If you really want to know whether there's anything that can be done with it, we'd need a short sample with the noise and the required speech, in its original format (no compressed MP3). The one thing I can be reasonably sure about is that it won't involve the 'DeNoiser' tool (it never does...)
The most powerful tool for NR in Audition is the process-based Noise Reduction tool. With your AIFF sample (which still cuts off rather abruptly at about 16kHz, making me a little suspicious about its origin), I've tried taking a noise print from the start, setting the FFT to its maximum and only removing about 3dB of noise at a single pass, and then resampling for another go with a lower FFT. This is the most cautious you can get with NR, pretty much. And at the end of the second pass, it became obvious that this was never going to become properly usable audio, I'm afraid - the speech is almost completely buried in the noise, which inevitably gets modulated by it. After five passes, I could hear a few of the words, but by this stage, even with minimal swipes at it, it's nowhere near usable. I even tried it with iZotope's RX, which is the most effective NR you can get, and got no further.
I'm afraid that you are going to have to tell your boss that the processing miracles you see on CSI don't actually happen in the real world. The audio that got recorded on that plane is, regrettably, unsalvageable. You don't have to take my word for this - you can try it yourself, using the same method. Nothing else is even going to get close.
I really appreciate your attempt and your time sir! Thank you very much!