Refer to figure.
All aircraft, both aeroplanes and helicopters have stipulated Centre of Gravity (CG) ranges. The ranges are the distance between forward and rearward as well as left and right allowable CG measured in inches/metres. The CG range is shown in the Helicopter Flight Manual (HFM) and type certification sheets in the form of a CG envelope.

Besides CG envelope, all aircrafts, both aeroplanes and helicopters have a maximum allowable gross mass known as All Up Weight (AUW).

Therefore, the criteria for correct loading of a helicopter include ensuring that the weight and balance of the helicopter are within the limits specified by the manufacturer, and that the distribution of the useful load is correctly loaded to remain within the CG envelope.

Additionally, it is important to verify that the helicopter's performance capabilities, such as maximum take-off weight will not be exceeded with the current load. The cargo should be properly loaded and secured to prevent it from shifting during flight, and any hazardous materials must be properly labelled and stored in accordance with regulations.

Read off the longitudinal aft limit station 101 at both the right and left limits of the CG envelope and drop down to locate the left limit at station -2.5 in and right limit at station 2.0 in.