Recently I have been instructing in a 7A. I have built and fly a -6. Three flights ago, the 7A developed a deafening whistle. So loud it is hard to communicate through ANR headsets. We have removed the main gear fairings and wheel pants as well as an external camera mount in an effort to isolate the cause, no luck. It is influenced by air speed, increasing or decreasing in volume as speed increases or decreases. Non existent below 110 mph. Any ideas besides flying around at 109 mph? Thanks for the input!
Joe
Joe