Interesting discussion.....I took some readings for my plane in each of the quadrants and the LOUDEST was directly in front of the plane! I would assume it would have been at the rear or back of the plane.

And David, I was told 'all planes have to be sound tested'...so even before my son flew he was asked to have his measured - and of course we put on a new prop the night before but it came out to an even 100dB at the 'dotted' line (circle) that was 'expertly measured'.

I still contend the REAL measurement is the noise level measured along the 'Dam' to the south....but that doesn't count So if I see you out there on Saturday morning - be prepared to me 'measured'

Jerry