Return-Path: Sender: (Marvin Kaye) To: lml Date: Thu, 04 Jul 2002 23:08:17 -0400 Message-ID: X-Original-Return-Path: Received: from imo-d02.mx.aol.com ([205.188.157.34] verified) by logan.com (CommuniGate Pro SMTP 4.0b4) with ESMTP id 1601865 for lml@lancaironline.net; Thu, 04 Jul 2002 22:37:02 -0400 Received: from Sky2high@aol.com by imo-d02.mx.aol.com (mail_out_v32.21.) id q.80.1dedbdf5 (4414) for ; Thu, 4 Jul 2002 22:36:59 -0400 (EDT) From: Sky2high@aol.com X-Original-Message-ID: <80.1dedbdf5.2a56604a@aol.com> X-Original-Date: Thu, 4 Jul 2002 22:36:58 EDT Subject: Re: [LML] Re: Quality Sound Proofing X-Original-To: lml@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="part1_80.1dedbdf5.2a56604a_boundary" X-Mailer: AOL 7.0 Plus for Windows US sub 2001 --part1_80.1dedbdf5.2a56604a_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 7/4/2002 5:12:09 PM Central Daylight Time, Newlan2dl@aol.com writes: > Making an aircraft quiet should address three things and in this order: > 1. Keep the noise out > 2. Absorb the noise that gets in > 3. Control and quiet structure born noise coming in. > Dan, Great post. LNC2s have certain noise problems only solved by ANC headsets. Re 1 Above - There are two major uncontrollable noise sources - The cockpit ventilation NACA ducts (when open) and the enormous bubble canopy, especially if you have an older kit, one made with an eighth-inch thick material. Re 2 - The aft face of the firewall is a good candidate for barrier and absorption; the floor carpeting, side panel foam and fabric and seat cushion material do a good job with exhaust noise. Re 3 - Foam stuffed in the forward D-section of the stub wing holds down the "sound-box" effect of that space. Everything else needs a good ANC headset. Scott Krueger N92EX --part1_80.1dedbdf5.2a56604a_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 7/4/2002 5:12:09 PM Central Daylight Time, Newlan2dl@aol.com writes:
Making an aircraft quiet should address three things and in this order:
1.    Keep the noise out
2.    Absorb the noise that gets in
3.    Control and quiet structure born noise coming in.

Dan,

Great post.  LNC2s have certain noise problems only solved by ANC headsets.

Re 1 Above - There are two major uncontrollable noise sources -  The cockpit ventilation NACA ducts (when open) and the enormous bubble canopy, especially if you have an older kit, one made with an eighth-inch thick material.

Re 2 - The aft face of the firewall is a good candidate for barrier and absorption; the floor carpeting, side panel foam and fabric and seat cushion material do a good job with exhaust noise.

Re 3 - Foam stuffed in the forward D-section of the stub wing holds down the "sound-box" effect of that space. 

Everything else needs a good ANC headset.

Scott Krueger
N92EX --part1_80.1dedbdf5.2a56604a_boundary--