Sender: <marv@lancaironline.net> (Marvin Kaye)
To: lml
Date: Tue, 11 Mar 2003 01:05:36 -0500
Message-ID: <redirect-2048977@logan.com>
From: Newlan2dl@aol.com
Subject: Re: [LML] Re: Lancair acoustic testing
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Hi Scott

You bring up a lot of excellent points and have some good data.  That brings 
up a lot of questions:

1.    Did you stick the dB meter all around the plane to see where the other 
noise leaks were?  Like how is the back of the firewall at the penetrations?

2.    That's interesting about the baggage compartment.  It was one area I 
suspected and was going to test.  So did you try adding insulation there to 
the bulkhead or just test it with and without it being installed? And how 
well does it fit around the edges? A LOT of noise can escape through a VERY 
small gap.  

3.    Did you check around the canopy for air coming under the frame, around 
the hinges, etc?  A lot of noise is aerodynamic and is from boudary layer 
buffeting.  It is often the dominant noise factor in large jets.

4.    When you did your testing, was the noise meter set to dB "A" scale or 
"C" scale?

5.    Excellent observation on the air vents.  What was the open and closed 
vent readings?

6.    Do you know what the weight of your insulation kit was?

Thanks again for the info!

Dan