Return-Path: Sender: (Marvin Kaye) To: lml Date: Fri, 10 Jan 2003 10:28:20 -0500 Message-ID: X-Original-Return-Path: Received: from imo-m09.mx.aol.com ([64.12.136.164] verified) by logan.com (CommuniGate Pro SMTP 4.0.3) with ESMTP id 1970204 for lml@lancaironline.net; Fri, 10 Jan 2003 10:14:35 -0500 Received: from Sky2high@aol.com by imo-m09.mx.aol.com (mail_out_v34.13.) id q.70.28f16ed6 (30960) for ; Fri, 10 Jan 2003 10:14:25 -0500 (EST) From: Sky2high@aol.com X-Original-Message-ID: <70.28f16ed6.2b503d51@aol.com> X-Original-Date: Fri, 10 Jan 2003 10:14:25 EST Subject: Re: [LML] Wing Loading mysteries X-Original-To: lml@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="part1_70.28f16ed6.2b503d51_boundary" X-Mailer: AOL 8.0 for Windows US sub 490 --part1_70.28f16ed6.2b503d51_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 1/10/2003 7:37:33 AM Central Standard Time, IIP@hawaii.rr.com writes: > And what is the relationship (if any) to the fact that > the 98 sq.ft. Lancair IV wing sustained 12,000 lbs. during a static > test? Oops, I forgot to finish, Static G-loading: Lancair is very conservative. In a type certificated airplane, the max G-load is 1.5 x (POH value) x max gross weight. Lancair typically uses 2 x (POH value) x max gross weight. This means that the P wings were probably tested to 2 x 4.4 x 3200 = 28160 or about 14000 pound per wing. If it was 12000 pounds, the safety factor would be 24000/3200=7.5/4.4=1.7, still greater than FAA requirements of 1.5. So what? At gross weight- Max structural cruising speed (Vno, top of green arc) is that speed at which max G-loading would occur if vertical gusts of a certain speed hit the wing (turbulence). Maneuvering Speed (Va) is the speed at which full deflection of the control surfaces (usually the elevator) would result in the max G-loading. Scott Krueger N92EX --part1_70.28f16ed6.2b503d51_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 1/10/2003 7:37:33 AM Central Standard Time, IIP@hawaii.rr.com writes:

And what is the relationship (if any) to the fact that
the 98 sq.ft. Lancair IV wing sustained 12,000 lbs. during a static
test?


Oops, I forgot to finish,

Static G-loading: Lancair is very conservative.  In a type certificated airplane, the max G-load is 1.5 x (POH value) x max gross weight.  Lancair typically uses 2 x (POH value) x max gross weight.  This means that the P wings were probably tested to 2 x 4.4 x 3200 = 28160 or about 14000 pound per wing.  If it was 12000 pounds, the safety factor would be 24000/3200=7.5/4.4=1.7, still greater than FAA requirements of 1.5.

So what?

At gross weight-
Max structural cruising speed (Vno, top of green arc) is that speed at which max G-loading would occur if vertical gusts of a certain speed hit the wing (turbulence).

Maneuvering Speed (Va) is the speed at which full deflection of the control surfaces (usually the elevator) would result in the max G-loading.

Scott Krueger
N92EX --part1_70.28f16ed6.2b503d51_boundary--