Looking For W&B Using Arm Instead of Moment

the upward sloping line on these graphs is the computed weight x arm =
moment and then the CG is read..




"Robert Moore" wrote in message
...
"John T" wrote
For instance, every W&B graph I've seen (Skyhawks, Skylanes,
C150s, Warriors, Katanas, Tomahawks - all under 35 years old)
have shown this graph using only weight/moment. All the sample
loading problems I've seen have all used moment instead of arm,
too.

In those airplanes, the "arm" is generally fixed by the location
of the seats and bagage compartment. On the graphs, the upward
sloping lines each represent a different arm. Regardless of how
it is presented, a w/b calculation always involves weights and
arms. Moment is simply weight times the arm.

Bob Moore

"BTIZ" wrote

the upward sloping line on these graphs is the computed weight x
arm = moment and then the CG is read..

In my C-172 manual, the upward sloping lines have no units.
One enters the chart on the left with weight, goes over to the
appropriate diagonal line (front seat, rear seat, baggage) and
then drops down to the base line and reads moment.

Bob Moore

Ron Natalie wrote:


I'm sure you're confused. The CG point is always an arm. A moment tells
you NOTHING about the CG. A moment of 1000 could be 1000 pounds at the
datum or 1 pound 1000 units away from the datum. If you've computed the
moment, you divide that by the weight to get the arm.


The 1986 Cessna Skyhawk manual presents the W&B data in both Weight vs
Moment and Weight vs CG.

John Roncallo

(Karl Medcalf) wrote in
:

I wrote a weight & balance program some time ago that will display the
envelope either way. If you're interested in looking at it, you can
find it at http://users3.ev1.net/~medcalf/avinfo.html

As noted, I accept no liability for use of the program, as you are
still responsible to properly calculate weight & balance for your
specific plane.

Enjoy.

I've downloaded and used Karl's program. I have it running on Windows 2000
Professional and am quite impressed. I highly recommend it.

--
John Godwin
Silicon Rallye Inc.