Section 6
Columbia 400 (LC41-550FG)
Weight & Balance
Initial Issue of Manual: November 10, 2004
RC050002
Latest Revision Level/Date: -/11-10-2004
6-9
8. Finally, the total moments and corrected weights are summed. In the example below, the
total weight is 2,485 pounds and the total moments are 260,432.5 lbs.-inches. All this
information is summarized in Figure 6 - 8. All required data for determining the empty
center of gravity are now available.
Scale
Location
Weight
Reading (lbs.)
Tare or Scale
Error
Corrected
Weight (lbs.) X
Arm
(Inches)
=
Moments
(lbs.- inches)
Right Main
Gear
992
-1
991
X 121.1
=
120,010.1
Left Main
Gear
991
-2
989
X 121.1
=
119,767.9
Nose Gear
502
+3
+505
X 40.9
=
+20,654.5
Total Empty Weight and Empty Moments
2485.0
260,432.5
Figure 6 - 8
9. The formula for determining empty weight center of gravity is shown in Figure 6 - 9; in the
example below, the empty center of gravity of the airplane is at fuselage station (FS) 104.8.
Total
Moments 260,432.5
lbs.-incbes
Empty
Weight
=
Center of
Gravity
or
2695
= 104.8
Figure 6 - 9
CHANGES IN THE AIRPLANE’S CONFIGURATION
1.
Determining Location (FS) of Installed Equipment in Relation to the Datum –
If
equipment is installed in the airplane, the weight and balance information must be updated.
Individuals and companies who are involved with equipment installations and/or
modifications are generally competent and conversant with weight and balance issues. These
individuals or companies must be aware that the fixed reference point is located at fuselage
station (FS) 97.05. Please see Figure 6 - 2 on page 6-5 for more information.
2.
Weight and Balance Forms –
There is a form that is inserted after Appendix A of Chapter
6 of the
AFM/POH
that is used to track changes in the configuration of the airplane. When
equipment is added or removed, these pages or an appropriate approved form must be
updated. In either instance the required information is similar.
3.
Updating the Form –
Fill in the date the item is added or removed, a description of the
item, the arm of the item, its weight, and the moment of the item. Remember, multiply the
weight times the arm of the item to obtain the moment. Finally, compute the new empty
weight and empty moment by adjusting the running totals. If an item is removed, subtract
the weight and moment of the item from the running totals. If an item is added, add the
weight and moment of the item to the running totals.