AM.I.C.K6

From the FAA library

• Helicopter Flying Handbookp. 6-4
  Chapter 6: Weight and Balance › Weight and Balance Calculations › Reference Datum

  Reference Datum Balance is determined by the location of the CG, which is usually described as a given number of inches from the reference datum. The horizontal reference datum is an imaginary vertical plane or point, arbitrarily fixed somewhere along ... actual weights if they are available, especially if the helicopter is loaded near the weight and balance limits. purposes. There is no fixed rule for its location. It may be located at the rotor mast, the nose of the helicopter…

• Aviation Maintenance Technician Handbook - Generalp. 6-2
  Chapter 6: Aircraft Weight & Balance › Weight & Balance Terminology › Moment

  accurately measured. When the arm for a piece of equipment is being determined, the measurement is taken from the datum to the piece of equipment’s own CG. Moment To understand balance, it is necessary to have a working knowledge ... moment, which is expressed in inch-pounds (in-lb), a point through which the force acts. For the purpose of illustration, compare an aircraft to a seesaw. Like the seesaw, for an aircraft to be in balance, or equilibrium…

• Aviation Maintenance Technician Handbook - Generalp. 6-5
  Chapter 6: Aircraft Weight & Balance › Procedures for Weighing an Aircraft › General Concepts

  clearly not realistic. Even if it could be done, determining where in the airplane the lines intersect would be difficult. A more realistic way to find the CG for an object, especially an airplane, is to place ... being the datum (zero arm), and 6 weights placed at various locations along the length of the plank. The purpose of Figure 6-6 is to show how the CG can be calculated when the arms and weights…