If the center of gravity is too far aft, an unstable tail-heavy condition is created, thereby increasing the tendency of the aircraft to stall. This condition definitely limits low power and may adversely affect the long-range optimum speed of the aircraft. In the extreme condition, this location of the center of gravity may cause a stall during an updraft of air. It definitely decreases the speed and range of the aircraft and increases pilot strain during instrument flying. There is also a tendency to aggravate the deicer effect on high-wing aircraft.

A standard program for weight and balance control has been established to aid in the prevention and correction of unsatisfactory flight conditions resulting from improper loading. The result has been greater safety and operating efficiency. Under this system, weight and balance can be checked for takeoff and landing conditions and for changes during flight by calculations, or by use of balance computers. A balance computer (sometimes called a load adjuster) is a precision calculating instrument similar in operation and appearance to a slide rule.

WEIGHT AND BALANCE SYSTEM

The requirements, procedures, and responsibilities for weight and balance control of Navy aircraft are listed in USN Aircraft Weight and Balance Control, NA 01-1B-50. This technical manual lists the two weight and balance classifications for Navy aircraft, class 1 and class 2 (fig. 6-20).

Figure 6-20.-Weight and Balance Classification of Naval Aircraft.