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Date: Sun, 16 Jan 2005 10:54:37 -0700
From: Bob White <bob@bob-white.com>
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
Subject: Re: [FlyRotary] Re: Engine mounts
Message-Id: <20050116105437.4d8fdc97.bob@bob-white.com>
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I though I could post a picture of my rear mount, but it seems to be
lost in the many gigabytes on my hard drive.  Basically it is a 1/2" rod
with the rubber cushioned rod ends as described by Jerry.  The upper
mount point was bolted to the two tabs on the front cover (I don't think
all front covers have them).  The lower end is connected to the bottom
of the firewall where there used to be a nose gear attachment point.  In
other words, I'm pushing up from the bottom instead of hanging down as
shown in Jerry's photo.

This arrangement is more unstable than the hanging alternative but it
seems very solid with no tendency of the rear of the engine to move left
or right.  I'll check again with prop loads.

The weight on the rear mount has been estimated to be on the order of 50
lbs.  I'm not sure I believe this number especially since I have the MM
plate instead of the S-beam.  One of the things on my todo list is to
measure the weight after I get a prop installed.

Bob White


On Sun, 16 Jan 2005 12:35:55 -0500
Jerry Hey <j-winddesigns@thegrid.net> wrote:

>=20
> On Sunday, January 16, 2005, at 12:18  PM, Al Gietzen wrote:
>=20
> > The short answer is Yes.=A0 The engine mount I build is called an
> > S-beam
> >
> > (Schertz Beam) mount.=A0 The concept was first developed by Bill
> > Schertz
> >
> > and was modified by Paul Lamar and others until it evolved into the
> >
> > present configuration.=A0 The S-beam mount only supports the front of
> > the
> >
> > engine.=A0 The rear engine support is provided by a adjustable=A0 strut
> >
> > that runs=A0 from "someplace" on the back of the engine to "someplace"
> > on
> >
> > the firewall.=A0=A0
> >
> > =A0
> >
> > I guess which is the _front_ of the engine is a relative term. =A0I=20
> > conclude it primarily supports the flywheel end. It appears=20
> > structurally very sound, but I wonder why there are struts along the
> >  engine bulkhead between the support points.=A0 Those would only be=20
> > needed if the bulkhead (or structure between the attach points) was=20
> > not structurally sound.
> >
> >
> > Al
>=20
> That structure is part of the Tailwind landing gear mount.  RV  tail=20
> dragger  is the same.  Jerry
> >
> > =A0
> >
>=20


--=20
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