What must be achieved for the accurate weighing of an aircraft?

For the accurate weighing of an aircraft, it is essential that the aircraft is in a level flight condition. This ensures that the weight distribution is uniform and that the scales or weighing equipment provide a true representation of the aircraft's total weight. When the aircraft is level, the center of gravity is aligned properly, which minimizes discrepancies caused by uneven weight distribution.

When an aircraft is in a nose-down attitude, it can lead to an inaccurate reading as the weight might be disproportionately distributed towards the front. Removing all fluids would not provide an accurate weight for operational purposes, as the aircraft should be weighed in a condition that reflects typical operational scenarios. Additionally, weighing an aircraft while it is in flight at cruising altitude is impractical and not a common practice, as the dynamics of flight would complicate the measurement process. Therefore, achieving level flight is a critical aspect of the weighing process for accuracy.