What variable is represented by 'W' in the weight shift formula?

In the context of weight shift formulas used in aviation, 'W' typically represents the Gross Weight of the aircraft. Gross weight refers to the total weight of the aircraft, including the aircraft itself, passengers, cargo, and fuel at the time of takeoff. Understanding gross weight is essential for pilots, as it affects various performance factors such as takeoff distance, climb rate, and fuel consumption.

When considering the weight shift formula, pilots use gross weight to ensure that the aircraft is within its safe operating limits. This factor is crucial in determining stability, control, and overall aircraft performance. The other options focus on specific components of the total weight but do not encompass the overall weight considerations necessary for weight and balance calculations. Thus, identifying 'W' as the Gross Weight provides a comprehensive understanding of the aircraft's total loading condition.