X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Tue, 15 Jan 2013 13:57:00 -0500 Message-ID: X-Original-Return-Path: Received: from mail-yh0-f51.google.com ([209.85.213.51] verified) by logan.com (CommuniGate Pro SMTP 6.0.1) with ESMTPS id 6013706 for lml@lancaironline.net; Tue, 15 Jan 2013 13:33:05 -0500 Received-SPF: pass receiver=logan.com; client-ip=209.85.213.51; envelope-from=mehapgood@gmail.com Received: by mail-yh0-f51.google.com with SMTP id f73so87473yha.10 for ; Tue, 15 Jan 2013 10:32:29 -0800 (PST) X-Received: by 10.236.84.77 with SMTP id r53mr88834529yhe.36.1358274749162; Tue, 15 Jan 2013 10:32:29 -0800 (PST) X-Original-Return-Path: Received: from [192.168.2.96] (rrcs-70-61-86-226.midsouth.biz.rr.com. [70.61.86.226]) by mx.google.com with ESMTPS id s2sm14723974ani.9.2013.01.15.10.32.16 (version=TLSv1 cipher=RC4-SHA bits=128/128); Tue, 15 Jan 2013 10:32:27 -0800 (PST) X-Original-Sender: Matt Hapgood User-Agent: Microsoft-MacOutlook/14.2.5.121010 X-Original-Date: Tue, 15 Jan 2013 13:31:43 -0500 Subject: Re: [LML] Re: Max Gross 360 LNC2 From: Matt Hapgood X-Original-To: Lancair List X-Original-Message-ID: Thread-Topic: [LML] Re: Max Gross 360 LNC2 In-Reply-To: Mime-version: 1.0 Content-type: multipart/alternative; boundary="B_3441101545_20411322" > This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible. --B_3441101545_20411322 Content-type: text/plain; charset="US-ASCII" Content-transfer-encoding: 7bit If I could do it all over again, I would build my plane 150 pounds lighter so I didn't have to go through the flight testing to feel only half-way decent about flying it at 1950 lbs. My hindsight is probably about 20-40. Matt From: Rob Murawski Reply-To: Lancair List Date: Tuesday, January 15, 2013 1:22 PM To: Lancair List Subject: [LML] Re: Max Gross 360 LNC2 With all of this discussion on max gross weights for the Lancair 320/360, what is the engineering/design decisions that has gone into increasing the gross weight? The reason I ask is that, I assume, the factory has done some type of engineering analysis. The factory increase in gross weight document is: http://www.lancair.com/media/builderupdates/235-320-360/Non-PDF-Docs/WeightI ncrease320-360.pdf Here, it states that the new main gear overcenter link must be used (Standard in kits produced after 10/93), the stall speed will be increased, and the allowable G limits are reduced to +4.0/-2.0. (Those reduced G limits aren't normally a problem for me) The maximum landing weight has not been changed. In Mac McClellan's blog http://macsblog.com/2011/08/when-a-kit-aircraft-is-not-a-kit-aircraft/ he asserts that all changes to a kit make each one a one-off. He refers to Dick (Van's) VanGrunsven's article about the engineering that goes into setting the RV-10's gross weight: http://macsblog.com/wp-content/uploads/2011/08/94-99_Handbook_v6.pdf While Van (nor I) dispute that there are airplanes flying around (successfully) with higher gross weights, I'm concerned that I do not have the engineering background to justify any gross weight other than to use what the factory provides. Vans asserts that the built-in engineering margin belongs to the designer and you can't have it. In particular, does the G loading become so low that I'd have to be concerned about turbulence breaking my wings off? I have no idea. Granted, the 360 has a lot of factory options. And I agree that no two are probably alike. But I feel a little better while building mine that I'm sticking to something that a real aeronautical engineer designed and approved. (That is meant that *I* do not have the aeronautical engineering skills to make that determination, I can't speak for anyone else) Thoughts? I have no idea what mine will weigh when finished. But I know the girlfriend likes to pack heavy. Might be time to look for a 4-place... -Rob (Lancair 360 MKII, 15% completed) -- For archives and unsub http://mail.lancaironline.net:81/lists/lml/List.html --B_3441101545_20411322 Content-type: text/html; charset="US-ASCII" Content-transfer-encoding: quoted-printable
If I could do it a= ll over again, I would build my plane 150 pounds lighter so I didn't have to= go through the flight testing to feel only half-way decent about flying it = at 1950 lbs.  My hindsight is probably about 20-40.

Matt

From: Rob Murawski <rob@robmurawski.com= >
Reply-To: Lancair List &l= t;lml@lancaironline.net>
Date: Tuesday, January 15, 2013 1:22 PM=
To: Lancair List <lml@lancaironline.net>
Subject: [LML] Re: Max Gross 360 LNC2
<= br>
With all of this discussion on max gross weights for= the Lancair 320/360,
what is the engineering/design decisions tha= t has gone into increasing the
gross weight?  The reason= I ask is that, I assume, the factory has done some
type of engine= ering analysis.  The factory increase in gross weight document
is:

ncrease320-360= .pdf

Here, it states that the new main gear overcen= ter link must be used
(Standard in kits produced after 10/93), the= stall speed will be increased,
and the allowable G limits are red= uced to +4.0/-2.0. (Those reduced G limits
aren't normally a probl= em for me)  The maximum landing weight has not been
chan= ged.

In Mac McClellan's blog
=
asserts that all changes to a kit make each one a one-off.  H= e refers to
Dick (Van's) VanGrunsven's article about the engineeri= ng that goes into
setting the RV-10's gross weight:
h= ttp://macsblog.com/wp-content/uploads/2011/08/94-99_Handbook_v6.pdf

While Van (nor I) dispute that there are airplanes flyi= ng around
(successfully) with higher gross weights, I'm concerned = that I do not have
the engineering background to justify any gross= weight other than to use
what the factory provides.  Va= ns asserts that the built-in engineering
margin belongs to the des= igner and you can't have it.

In particular, does th= e G loading become so low that I'd have to be
concerned about turb= ulence breaking my wings off?  I have no idea.

Granted, the 360 has a lot of factory options.  And I agree = that no two are
probably alike.  But I feel a little bet= ter while building mine that I'm
sticking to something that a real= aeronautical engineer designed and
approved.  (That is = meant that *I* do not have the aeronautical engineering
skills to = make that determination, I can't speak for anyone else)

=
Thoughts?

I have no idea what mine will weigh = when finished.  But I know the
girlfriend likes to pack = heavy. Might be time to look for a 4-place...

-Rob&= nbsp; (Lancair 360 MKII, 15% completed)

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