Once you are satisfied that the total weight is within prescribed limits, multiply each individual weight by its associated arm to determine its moment. Then, add the moments together to arrive at the total moment for the helicopter. Your final computation is to find the center of gravity of the loaded helicopter by dividing the total moment by the total weight. After determining the helicopter’s weight and center of gravity location, you need to determine if the CG is within acceptable limits. In this example, the allowable range is between 106.0 inches and 114.2 inches. Therefore, the CG location is within the acceptable range. If the CG falls outside the accept- able limits, you will have to adjust the loading of the helicopter. You can determine if a helicopter is within weight and CG limits using a loading chart similar to the one in figure 7-6. To use this chart, first subtotal the empty weight, pilot, and passengers. This is the weight at which you enter the chart on the left. The next step is to follow the upsloping lines for baggage and then for fuel to arrive at your final weight and CG. Any value on or inside the envelope is within the range. Point C is within allowable weight and CG limits. Assume that the pilot in sample problem 1 discharges the passenger after using only 20 pounds of fuel. Determine if the gross weight and center of gravity are within allowable limits under the following loading conditions for a helicopter based on the loading chart in figure 7-6. Follow the blue arrows in figure 7-6, starting at 1,175 lb. on the left side of the graph, then to point D, E, and F. Although the total weight of the helicopter is well below the maximum allowable gross weight, point F falls outside the aft allowable CG limit. As you can see, it is important to reevaluate the balance in a helicopter whenever you change the loading. Unlike most airplanes, where discharging a passenger is unlikely to adversely affect the CG, off-loading a pas- senger from a helicopter could make the aircraft unsafe to fly. Another difference between helicopter and air- plane loading is that most small airplanes carry fuel in the wings very near the center of gravity. Burning off fuel has little effect on the loaded CG. However, heli- copter fuel tanks are often significantly behind the center of gravity. Consuming fuel from a tank aft of the rotor mast causes the loaded helicopter CG to move forward. As standard practice, you should compute the weight and balance with zero fuel to verify that your helicopter remains within the acceptable limits as fuel is used. To use the loading chart for the helicopter in this exam- ple, you must add up the items in a certain order. The maximum allowable gross weight is 1,600 pounds. 7-5 Figure 7-6. Loading chart illustrating the solution to sample problems 1 and 2. LOADING CHART METHOD SAMPLE PROBLEM 1 SAMPLE PROBLEM 2 1. Follow the green arrows in figure 7-6. Enter the graph on the left side at 1,375 lb., the subtotal of the empty weight and the passenger weight. Move right to the yellow line. (point A) 2. Move up and to the right, parallel to the baggage compartment loading lines to 1,400 lb. (Point B) 3. Continue up and to the right, this time parallel to the fuel loading lines, to the total weight of 1,580 lb. (Point C). ITEM POUNDS Basic empty weight 1,040 Pilot 135 Subtotal 1,175 (point D) Baggage compartment load 25 Subtotal 1,200 (point E) Fuel load 160 Total weight 1,360 (point F) ITEM POUNDS Basic empty weight 1,040 Pilot 135 Passenger 200 Subtotal 1,375 (point A) Baggage compartment load 25 Subtotal 1,400 (point B) Fuel load (30 gallons) 180 Total weight 1,580 (point C) A B C D F 1,600GLYPH<.notdef> GLYPH<.notdef> 1,500GLYPH<.notdef> GLYPH<.notdef> 1,400GLYPH<.notdef> GLYPH<.notdef> 1,300GLYPH<.notdef> GLYPH<.notdef> 1,200GLYPH<.notdef> GLYPH<.notdef> 1,100 104 105 106 107 108 109 Baggage CompartmentGLYPH<.notdef> Loading Lines Fuel LoadingGLYPH<.notdef> Lines E