X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Wed, 13 Jul 2005 13:15:12 -0400 Message-ID: X-Original-Return-Path: Received: from imo-d22.mx.aol.com ([205.188.144.208] verified) by logan.com (CommuniGate Pro SMTP 4.3.6) with ESMTP id 1054935 for lml@lancaironline.net; Wed, 13 Jul 2005 11:07:51 -0400 Received-SPF: pass receiver=logan.com; client-ip=205.188.144.208; envelope-from=Sky2high@aol.com Received: from Sky2high@aol.com by imo-d22.mx.aol.com (mail_out_v38_r1.7.) id q.7f.61fa900f (16633) for ; Wed, 13 Jul 2005 11:07:00 -0400 (EDT) From: Sky2high@aol.com X-Original-Message-ID: <7f.61fa900f.30068813@aol.com> X-Original-Date: Wed, 13 Jul 2005 11:06:59 EDT Subject: Re: [LML] Re: LNC2, C.G. prognosis appreciated X-Original-To: lml@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="-----------------------------1121267219" X-Mailer: 9.0 Security Edition for Windows sub 5009 -------------------------------1121267219 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Tim, Many years ago when Lancair "created" the long engine mount (engine moved 3 " fwd) they noted that it moved the CG forward 1.5 inches and caused no difficulty with handling. Some flyers had found that retro-fitting the large tail had moved the CG back into dangerous territory even though the new tail tail had been built of light weight carbon, it was heavier and its' arm was long enough to adversely affect the CG. Since everything is part of a system, your test flying with a super forward CG will have to determine if there is enough nose up elevator authority during the landing flare - remember that the 320/360 flaps have a great affect on the pitching moment and should there not be enough nose up authority, retracting some flap can help bring the nose up. 320/360s do not like flight with a rearward CG - even a CG short of the aft limit. Once again, this can be helped somewhat by putting in a little bit of flap (nose down pitch). Generally, these Lancairs seem to like more forward CG. Yes, the flaps can be used to assist pitch trim if there is a problem (within reasonable operating speeds for minor flap deployments). Sometimes I think the published CG range was calculated with the wing in its' "neutral" position (flaps at 0 degrees) while we actually fly it in "reflex" (-7 degrees) where the wing center of lift has changed requiring a goodly amount of nose down pitch trim (gee, just like when the CG goes to the back). Of course, landing with full flaps requires quite a bit of nose up trim. Scott Krueger AKA Grayhawk Lancair N92EX IO320 SB 89/96 Aurora, IL (KARR) -------------------------------1121267219 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable
Tim,
 
Many years ago when Lancair "created" the long engine mount (engine mov= ed 3=20 " fwd) they noted that it moved the CG forward 1.5 inches and caused no=20 difficulty with handling. Some flyers had found that retro-fitting the=20 large tail had moved the CG back into dangerous territory even though the ne= w=20 tail tail had been built of light weight carbon, it was heavier and its= '=20 arm was long enough to adversely affect the CG. 
 
Since everything is part of a system, your test flying with a super for= ward=20 CG will have to determine if there is enough nose up elevator=20 authority during the landing flare - remember that the 320/360 flaps have a=20 great affect on the pitching moment and should there not be enough nose up=20 authority, retracting some flap can help bring the nose up.
 
320/360s do not like flight with a rearward CG - even a CG short of the= aft=20 limit.  Once again, this can be helped somewhat by putting in a li= ttle=20 bit of flap (nose down pitch).
 
Generally, these Lancairs seem to like more forward CG.
 
Yes, the flaps can be used to assist pitch trim if there is a problem=20 (within reasonable operating speeds for minor flap deployments).
 
Sometimes I think the published CG range was calculated with the wing i= n=20 its' "neutral" position (flaps at 0 degrees) while we actually fly it in=20 "reflex" (-7 degrees) where the wing center of lift has changed requiring a=20 goodly amount of nose down pitch trim (gee, just like when the CG=20= goes=20 to the back).
 
Of course, landing with full flaps requires quite a bit of nose up trim= .=20
 
Scott Krueger=20 AKA Grayhawk
Lancair N92EX IO320 SB 89/96
Aurora, IL=20 (KARR)



 -------------------------------1121267219--