Typically I leave the rotating beacon switched on - as a good reminder for myself in case I left the master engaged - so I'm pretty well used to hearing the beacon's motor turning.
Today, I was doing some work with the GPS in the hangar and so I turned off the rotating beacon and noticed another rotating motor type noise while the Master was on. I didn't have a ton of time to investigate- I will next time I'm at the hangar- but I noticed it was coming from the tail cone just below the ruddervators and in between the towel bar antennas. Seemed to be rotating once every 2-3 seconds at a consistent rate. I could feel a slight "thump" in the tail cone everytime it reached the peak of its motion.
It's possible the noise has always been there and just been masked by the sound of the beacon, but any thoughts as to what this could be?
Thanks in advance!