Return-Path: Sender: (Marvin Kaye) To: lml@lancaironline.net Date: Thu, 01 Jul 2004 22:27:13 -0400 Message-ID: X-Original-Return-Path: Received: from imo-m20.mx.aol.com ([64.12.137.1] verified) by logan.com (CommuniGate Pro SMTP 4.2b6) with ESMTP id 233845 for lml@lancaironline.net; Thu, 01 Jul 2004 19:15:16 -0400 Received: from Sky2high@aol.com by imo-m20.mx.aol.com (mail_out_v37_r2.6.) id q.15b.38ee141f (3866) for ; Thu, 1 Jul 2004 19:14:43 -0400 (EDT) From: Sky2high@aol.com X-Original-Message-ID: <15b.38ee141f.2e15f4e3@aol.com> X-Original-Date: Thu, 1 Jul 2004 19:14:43 EDT Subject: Re: [LML] Re: CG and Gross Weight X-Original-To: lml@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="-----------------------------1088723683" X-Mailer: 9.0 for Windows sub 5000 -------------------------------1088723683 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 7/1/2004 2:39:33 PM Central Standard Time, 5zq@cox.net writes: Here are the arms for our 320. The datum is the aft face of the firewall. Oil -24.0 Header tank 7.1 Wing tanks 37.8 Seats 43.0 Baggage (1) 63.0 * Baggage (2) 82.0 * Aft shelf 100.0 *Since the baggage area spans such a large range of arms, we broke it into the front half (1), and the aft half (2). Hope that these numbers help. Bill Harrelson N5ZQ LNC2 Long engine mount O-320 small tail standard gear Duane & Bill, Here's mine measured during very formal weigh in: I/O 320, Aft face of firewall datum, short mount, standard gear, small tail, slightly overweight pilot.... -13.1 = Oil 7.4 = Header 36.4 = Wing tanks 44.3 = Seats 67.5 = Baggage - Front limit arm 88.3 = Baggage - Aft limit arm 74.0 = Baggage arm used in W&B calculations since most stuff fits forward where it's wider. Eventually you will note that each aircraft is slightly different in W&B locations. Theoretically, the CG range is measured from the aft face of the firewall - this compensates for different engines, mounts, props, etc. Again, theoretically, the wing and the firewall haven't moved and neither has the CG range as measured from the aft face of the firewall. What Bill (and most others) don't report is the location of the wheels (plumb dropped from the axles, longeron level) and the weight on each for the empty weight with the canopy closed and latched. I.E. Mine: -6.75 432# Nose (extension angle can cause a difference) 37.5 398# Right Main (Battery, Hydro, etc, dressed right - usually fly solo) 37.5 385# Left Main (190 # Pilot added has left main carrying 30# more than right.) ---------- 1215# With a Moment of 26446, that yiedls an empty CG of about 21.8. You can figure out what the pilot must weigh with a full header tank in order to keep the CG within the forward suggested limit. Take some measurements and with some calculations and guesswork, you should be able to make some good judgements. Who knows how heavy your engine compartment will end up being - I used all steel braided liquid lines, fireshielded everything, mounted the oil cooler on the firewall, used a remote oil filter, used more than 3000 tie wraps, added heavy silicon baffle seals, etc. Who knows how much this would make my CG different than someone that used less heavy fluid lines, oil cooler on the front baffle, etc. Enjoy, Scott Krueger AKA Grayhawk Sky2high@aol.com II-P N92EX IO320 Aurora, IL (KARR) LML, where ideas collide and you decide! -------------------------------1088723683 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable

In a message dated 7/1/2004 2:39:33 PM Central Standard Time, 5zq@cox.n= et=20 writes:

<= FONT=20 style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size= =3D2>

Here are the arms fo= r our=20 320. The datum is the aft face of the firewall.

Oil = ;=20 = ;=20 -24.0

Header=20 tank 7.1

Wing tanks &nbs= p; =20 37.8

Seats &nb= sp;=20 43.0

Baggage=20 (1) 63.0 *

Baggage=20 (2) 82.0 *

Aft=20 shelf 100= .0

*Since the baggage a= rea=20 spans such a large range of arms, we broke it into the front half (1), and= the=20 aft half (2).

Hope that these numb= ers=20 help.

Bill Harrelson

N5ZQ =20 LNC2 Long engine mount O-320 &nbs= p;=20 small tail standard=20 gear

Duane & Bill,

Here's mine measured during very formal weigh in:

I/O 320, Aft face of firewall datum, short mount, standard gear, small=20 tail, slightly overweight pilot....

-13.1 =3D Oil

7.4 =3D Header

36.4 =3D Wing tanks

44.3 =3D Seats

67.5 =3D Baggage - Front limit arm

88.3 =3D Baggage - Aft limit arm

74.0 =3D Baggage arm used in W&B calculations since most stuf= f fits=20 forward where it's wider.

Eventually you will note that each aircraft is slightly different in=20 W&B locations. Theoretically, the CG range is measured from the af= t=20 face of the firewall - this compensates for different engines, mounts, props= ,=20 etc. Again, theoretically, the wing and the firewall haven't moved and= =20 neither has the CG range as measured from the aft face of the firewall.

What Bill (and most others) don't report is the location of the wheels=20 (plumb dropped from the axles, longeron level) and the weight on each=20= for=20 the empty weight with the canopy closed and latched.

I.E. Mine:

-6.75 432# Nose (extension angle can cause a difference)

37.5 398# Right Main (Battery, Hydro, etc, dressed right=20 - usually fly solo)

37.5 385# Left Main (190 # Pilot added has left main carryi= ng=20 30# more than right.)

----------

1215#

With a Moment of 26446, that yiedls an empty CG of about 21.8. Yo= u=20 can figure out what the pilot must weigh with a full header tank in order to= =20 keep the CG within the forward suggested limit.

Take some measurements and with some calculations and guesswork, you sh= ould=20 be able to make some good judgements. Who knows how heavy your engine=20 compartment will end up being - I used all steel braided liquid lines,=20 fireshielded everything, mounted the oil cooler on the firewall, used a remo= te=20 oil filter, used more than 3000 tie wraps, added heavy silicon baffle seals,= =20 etc. Who knows how much this would make my CG different than someone t= hat=20 used less heavy fluid lines, oil cooler on the front baffle, etc.

Enjoy,

Scott Krueger=20 AKA Grayhawk
Sky2high@aol.com
II-P N92EX IO320 Aurora, IL=20 (KARR)

LML, where ideas collide and you=20 decide!

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