OIL
FUEL TANK
FUEL TANK
Occupants
Front Seat
Arm 85
Rear Seats
Arm 121
Moment
100 Weight Moment
100 Weight
120
130
140
150
160
170
180
190
200
120
130
140
150
160
170
180
190
200
102
110
119
128
136
144
153
162
170
145
157
169
182
194
206
218
230
242
Usable Fuel
Main Wing Tanks Arm 75
WeightGallons Moment
100
5
10
15
20
25
30
35
40
44
30
60
90
120
150
180
210
240
264
22
45
68
90
112
135
158
180
198
Moment Limits vs Weight
Moment limits are based on the following weight and
center of gravity limit data (landing gear down).
2,950 lb (takeoff
or landing)
2,525 lb
2,475 lb or less
82.1
77.5
77.0
84.7
85.7
85.7
Forward
CG Limit
Weight
Condition
AFT
CG Limit
Moment
100 Weight
Baggage or 5th
Seat Occupant
Arm 140
10
20
30
40
50
60
70
80
90
100
110
120
130
140
150
160
170
180
190
200
210
220
230
240
250
260
270
14
28
42
56
70
84
98
112
126
140
154
168
182
196
210
224
238
252
266
280
294
308
322
336
350
364
378
Weight
Maximum
Moment
100
Minimum
Moment
100
1,800
1,808
1,817
1,825
1,834
1,843
1,851
1,860
1,868
1,877
1,885
1,894
1,903
1,911
1,920
1,928
1,937
1,945
1,954
1,963
1,971
1,980
1,988
1,997
2,005
2,014
2,023
2,031
2,040
2,048
2,100
2,110
2,120
2,130
2,140
2,150
2,160
2,170
2,180
2,190
2,200
2,210
2,220
2,230
2,240
2,250
2,260
2,270
2,280
2,290
2,300
2,310
2,320
2,330
2,340
2,350
2,360
2,370
2,380
2,390
1,617
1,625
1,632
1,640
1,648
1,656
1,663
1,671
1,679
1,686
1,694
1,702
1,709
1,717
1,725
1,733
1,740
1,748
1,756
1,763
1,771
1,779
1,786
1,794
1,802
1,810
1,817
1,825
1,833
1,840
Weight
Maximum
Moment
100
Minimum
Moment
100
2,057
2,065
2,074
2,083
2,091
2,100
2,108
2,117
2,125
2,134
2,143
2,151
2,160
2,168
2,176
2,184
2,192
2,200
2,208
2,216
2,224
2,232
2,239
2,247
2,255
2,263
2,271
2,279
2,287
2,295
2,303
2,311
2,319
2,326
2,334
2,342
2,350
2,358
2,366
2,374
2,381
2,389
2,397
2,405
2,413
2,421
2,426
2,436
2,444
2,452
3,460
2,468
2,475
2,483
2,491
2,499
2,400
2,410
2,420
2,430
2,440
2,450
2,460
2,470
2,480
2,490
2,500
2,510
2,520
2,530
2,540
2,550
2,560
2,570
2,580
2,590
2,600
2,610
2,620
2,630
2,640
2,650
2,660
2,670
2,680
2,690
2,700
2,710
2,720
2,730
2,740
2,750
2,760
2,770
2,780
2,790
2,800
2,810
2,820
2,830
2,840
2,850
2,860
2,870
2,880
2,890
2,900
2,910
2,920
2,930
2,940
2,950
1,848
1,856
1,863
1,871
1,879
1,887
1,894
1,092
1,911
1,921
1,932
1,942
1,953
1,963
1,974
1,984
1,995
2,005
2,016
2,026
2,037
2,048
2,058
2,069
2,080
2,090
2,101
2,112
2,123
2,133
2,144
2,155
2,166
2,177
2,188
2,199
2,210
2,221
2,232
2,243
2,254
2,265
2,276
2,287
2,298
2,309
2,320
2,332
2,343
2,354
2,365
2,377
2,388
2,399
2,411
2,422
Sample Loading Problem Weight Moment
Basic empty weight 2,015 1,554
Fuel main tanks (44 gal) 264 198
*Front seat passengers 300 254
*Rear seat passengers 190 230
Baggage 30 42
Total 2,799 2,278/100
* Interpolate or, as in this case, add appropriate numbers.
Empty Weight ~ 2,015
MOM/ 100 ~ 1,554
*Oil
WeightQuarts Moment
100
10 19 5
*Included in basic empty weight
BAGGAGE AREA
SEATING AREA
Figure 10-9. Loading schedule placard.
way.) Once this has been done for each item, total the weight
and moments and draw a line for both weight and moment
on the CG envelope graph. If the lines intersect within the
envelope, the aircraft is loaded within limits. In this sample
loading problem, the aircraft is loaded within limits.
Table Method
The table method applies the same principles as the
computational and graph methods. The information
and limitations are contained in tables provided by the
manufacturer. Figure 10-9 is an example of a table and a
Item Weight Arm Moment
Basic empty weight Front seat occupants
3rd & 4th seat occupants
forward facing
5th & 6th seat occupants
Nose baggage
Aft baggage
Subtotal
Fuel
Subtotal ramp weight
* Less fuel for start,
taxi, and takeoff
Subtotal
takeoff weight
Less fuel to destination
Actual landing weight
*Fuel for start, taxi, and takeoff is normally 24 pounds.
3,230
335
350
200
100
25
4,240
822
5,062
−24
5,038
−450
4,588
292,315.0
29,815.0
44,100.0
31,400.0
1,000.0
4,575.0
403,205.0
92,886.0
496,091.0
−2,712.0
493,379.0
−50,850.0
442,529.0
CG 90.5
89.0
126.0
157.0
10.0
183.0
CG 95.1
113.0
CG 98.0
113.0
CG 97.9
113.0
CG 96.5
Zero fuel weight max 4,400 pounds
Ramp weight max 5,224 pounds
Max landing weight 4,940 pounds
Figure 10-11. Sample weight and balance using an aircraft with a
published zero fuel weight.
Item Weight Arm Moment
Licensed empty weight 1,011.9 68.6 69,393.0
Oil (6 quarts) 11.0 −31.0 −341.0
Fuel (18 gallons) 108.0 84.0 9,072.0
Fuel, auxiliary (18 gallons) 108.0 84.0 9,072.0
Pilot 170.0 81.0 13,770.0
Passenger 170.0 81.0 13,770.0
Baggage 70.0 105.0 7,350.0
Total 1,648.9 122,086.0
CG 74.0
Figure 10-10. Sample weight and balance using a negative.
weight and balance calculation based on that table. In this
problem, the total weight of 2,799 pounds and moment of
2,278/100 are within the limits of the table.
Computations With a Negative Arm
Figure 10-10 is a sample of weight and balance computation
using an aircraft with a negative arm. It is important to
remember that a positive times a negative equals a negative,
and a negative would be subtracted from the total moments.
Computations With Zero Fuel Weight
Figure 10-11 is a sample of weight and balance computation
using an aircraft with a zero fuel weight. In this example,
the total weight of the aircraft less fuel is 4,240 pounds,
which is under the zero fuel weight of 4,400 pounds. If the
total weight of the aircraft without fuel had exceeded 4,400
pounds, passengers or cargo would have needed to be reduced
to bring the weight at or below the max zero fuel weight.
Shifting, Adding, and Removing Weight
A pilot must be able to solve any problems accurately that
involve the shift, addition, or removal of weight. For example,
the pilot may load the aircraft within the allowable takeoff
weight limit, then find that the CG limit has been exceeded.
The most satisfactory solution to this problem is to shift
baggage, passengers, or both. The pilot should be able to
determine the minimum load shift needed to make the aircraft
safe for flight. Pilots should be able to determine if shifting a
load to a new location will correct an out-of-limit condition.
There are some standardized calculations that can help make
these determinations.
Weight Shifting
When weight is shifted from one location to another, the
total weight of the aircraft is unchanged. The total moments,
however, do change in relation and proportion to the
direction and distance the weight is moved. When weight is
moved forward, the total moments decrease; when weight
is moved aft, total moments increase. The moment change
is proportional to the amount of weight moved. Since many
aircraft have forward and aft baggage compartments, weight
may be shifted from one to the other to change the CG. If
starting with a known aircraft weight, CG, and total moments,
calculate the new CG (after the weight shift) by dividing the
new total moments by the total aircraft weight.
To determine the new total moments, find out how many
moments are gained or lost when the weight is shifted.
Assume that 100 pounds has been shifted from station 30 to
station 150. This movement increases the total moments of
the aircraft by 12,000 in-lb.
Moment when
at station 150 = 100 lb x 150 in = 15,000 in-lb
Moment when
at station 30 = 100 lb x 30 in = 3,000 in-lb
Moment change = [15,000 – 3,000] = 12,000 in-lb
By adding the moment change to the original moment (or
subtracting if the weight has been moved forward instead of
aft), the new total moments are obtained. Then determine the
new CG by dividing the new moments by the total weight:
Total moments =
616,000 in-lb + 12,000 in-lb = 628,000 in-lb
CG = 628,000 in-lb = 78.5 in
8,000 lb
The shift has caused the CG to shift to station 78.5.