You can add aircraft whistles to the "move" event of the external folder. There are no examples of this in the default structure, but it will work just the same. This per a conversation with Hitech on how to get this problem ironed out. It will not help to hear airplanes coming, because sounds are already distance attenuated. However, it will help to improve the battlefield effects.
In the Internal folder I suggest that the whistle sound from gunports be added as Referenced Events. This was the only way I could get SpeedMPH to work as a Parameter Sheet and modifier for the base sound.
Despite what I posted in my FMOD video I have since discovered that rather then pitch-shift a lot of engine/exhaust/tread sounds that FMOD can do this for you. It's the same technique, but there is no need to calculate for angular velocity, and any anomaly can be dealt with using the post-process effects.
Rather than take the time to make another video on how to use the AH2 sounds with AH3 I will just go ahead and tell you that the old engine sound (not start/stop) should have been recorded at 1500rpm, and that is the default for the HTC events project. FMOD will automatically handle the pitch shifting from there as long as you properly attach the engine sound.
I modified the tanks to use tread, suspension, and road wheel/bearing noise within the RPM tracks of Internal and External folders. This way as the tank slows down or speeds up the noise associated with movement also change and the result is as real as possible to the user and anyone close enough to hear it. That makes it possible to identify tanks more easily. I suggest dropping tank engine sounds Externally in favor of Exhaust sounds as they are more distinctive and really what you would hear anyway. So, the exhaust tread/suspension/bearings are the primary identifiers.
In doing this what I discovered is that the tank event structures must closely match the default, or the default sounds will still come through. That may be another FMOD bug.