Loading Graph $^{ }$Compute Weight and Balance Using the Loading  Graph Loading Graph Method Moment Indexes 5-4 Transfer totals to the CG moment envelope in  Figure 5-8 .  The CG moment envelope is an enclosed area on a graph  of the airplane loaded weight and loaded moment. If lines  drawn from the weight and loaded moment cross within  this envelope, the airplane is properly loaded. The loading  schedule from the example in  Figure 5-7  shows that the total  weight of the loaded aircraft is 3,027 pounds, and the loaded  airplane moment divided by 1,000 is 131.8. The charts and graphs found in the POH/AFM can help  simplify and expedite the preflight weight and balance  computation process. Some use a loading graph and moment  indexes rather than the arms and moments. These charts  eliminate the need for calculating moments and make  computations quicker and easier.  [Figure 5-6] Moments determined by multiplying the weight of each  component by its arm resultin large numbers that are awkward  to calculate and can become a source of mathematical error.  To eliminate these large numbers, moment indexes are  sometimes used. The moment is divided by a reduction  factor, such as 100 or 1,000, to get the moment index. The  loading graph provides the moment index for each component  to avoid mathematical calculations. The CG envelope uses  moment indexes rather than arms and moments. Determine the load moment for the fuel and the baggage  in areas A and B in the same way and enter them all in the  loading schedule chart. The maximum fuel is marked on  the diagonal line for fuel in terms of gallons or liters. The  maximum is 88 gallons of usable fuel. The total capacity is 92  gallons, but in our example, 4 gallons are unusable and have  already been included in the empty weight of the aircraft. The  weight of 88 gallons of fuel is 528 pounds and its moment  index is 24.6. The 100 pounds of baggage in area A has a  moment index of 9.7 and the 50 pounds in area B has an  index of 5.8. Enter all of these weights and moment indexes  in the loading schedule chart and add all of the weights and  moment indexes to determine the totals.  To compute the weight and balance using the loading graph  in  Figure 5-6 , make a loading schedule chart like the one  Figure 5-7 . In  Figure 5-6 , follow the horizontal line for  300 pounds load weight to the right until it intersects the  diagonal line for pilot and front passenger. From this point,  drop a line vertically to the load moment index along the  bottom to determine the load moment for the front seat  occupants. This is 11.1 lb-in divided by 1,000. Record it in  the loading schedule chart. Determine the load moment for  the 175 pounds of rear seat occupants along the diagonal for  second row passengers or cargo. This is 12.9; record it in the  loading schedule chart.  Figure 5-6  is a typical loading graph taken from the POH  of a modern four-place airplane. It is a graph of load weight  and load moment indexes. Diagonal lines for each item  relate the weight to the moment index without having to use  mathematical calculations. The CG limits envelope is the enclosed area on a graph of  the airplane loaded weight and the CG location. If lines  drawn from the weight and CG cross within this envelope,  the airplane is properly loaded. Figure 5-5.  CG limits chart from a typical POH. 3,200 3,100 3,000 2,950 2,900 2,800 2,700 2,600 2,500 2,400 2,300 2,200 2,100 2,000 1,900 1,800 1,450 1,400 1,350 1,300 1,250 1,200 1,150 1,100 1,050 1,000 950 900 850 +32  +34  +36  +38  +40  +42  +44  +46 850  900  950 1,000 1,050 1,100 1,150 1,200 Aircraft CG location Inches aft of datum (Sta. 0.0) Loaded aircraft weight (lb) Loaded aircraft weight (kg) Aircraft CG location Millimeters aft of datum (Sta. 0.0) CG limits Takeoff and landing only If takeoff weight is more than  landing weight of 2,950 pounds,  allow flight time for fuel burn-off  to 2,950 pounds before landing