What parameter is primarily checked during weight and balance measurements?

The aircraft's center of gravity is the primary parameter checked during weight and balance measurements because it directly affects the aircraft's stability and controllability. Maintaining the center of gravity within specified limits is crucial for safe flight operations. If the center of gravity is too far forward or too far aft, it can lead to difficulties in aircraft control, increased stall speed, and, in extreme cases, may even result in an inability to recover from an upset condition.

In weight and balance calculations, both the overall weight of the aircraft and the distribution of that weight in relation to the center of gravity must be carefully considered. Adjustments may need to be made based on passenger or cargo load, fuel levels, and other factors to ensure that the center of gravity remains within acceptable limits throughout the flight. This focus on the center of gravity is fundamental to ensuring the safety and performance of the aircraft during operations.