Bill Freeman wrote>

70 dB at a 1000 ft flyby is excellent.

Mark Wrathall wrote>
Tracy, thanks to you and Ed for the sterling work on 13b noise reduction.

In Austria, a home built gets a flight test permit (and an OE-Vxx
registration) initially. To get the final experimental-amatuer construction
certification (with a registration OE-Cxx 1-2 seats, or OE-D-xx 3+ seats as
with normal light aircraft) on top of completing the flight test program,
providing stablity data, doing take off roll measurments, creating a flight
manual, and dropping US$2000+ to the authorities, you have to perform a
noise signature measurement.

The bar is currently set at 64dB for the 1000' flyby at max engine power.
The figure of 60dB unfortunately keeps coming up as a future goal.

If any of you have heard (unlikely) a diamond Katana fly over - product of
Austria!

 
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