From: Sky2high@aol.com
Message-ID: <60.1811c98.26063b10@aol.com>
Date: Sun, 19 Mar 2000 09:15:44 EST
Subject: Further to LNC2 soundproofing and Noise levels in flight.
To: lancair.list@olsusa.com
Mime-Version: 1.0

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Hear me out here!

As reported previously, my Lancair 320 has the EAR/Lancair recommended 
soundproofing material installed on the aft firewall, floor and sides (back 
to the seatback) and in the interior leading edge of the stubwing (acts like 
a soundbox).  I have carpeting, foam-backed fabric and temperfoam seats 
covered with sheepskin.  I also have the older canopy 1/8 inch thick 
material.  

The following comparisons were made at the head with a sound level measuring 
device set to the "C" scale (broad range, slow reaction):

Db......Condition
90       Astro Van @ 70 mph
92       96 Corvette @ 75 mph, smooth road
95       85 Corvette @ 70 mph, smooth road
104     Lancair 320 at 25sq, 3000 ft, smooth air
106     Skymaster (C337) 24sq, 3000 ft, props synced, smooth air in the front.

Note, although I could hear a change in the noise content when I opened the 
air vents in the Lancair (rushing sound), there was no difference in the 
sound level.

I do wear Bose headsets.

NOTE:  Anybody within reasonable flying distance of Chicago can borrow the 
sound meter for comparison purposes.  If you are close enough, I can fly to 
you or meet for lunch halfway. (300 NM radius of KARR).

Scott Krueger
N92EX
Cell phone- 630-561-0400

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Please send your photos and drawings to marvkaye@olsusa.com.
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