What must be done to establish new weight and balance records if all records for an aircraft are missing?

To establish new weight and balance records for an aircraft when all previous records are missing, it is essential to accurately measure the aircraft's weight. This involves conducting a proper weight measurement using calibrated scales to determine the aircraft's total weight, including all installed equipment, fluids, and cargo to ensure precise data for weight and balance calculations.

Accurate weight measurements are critical because the weight and balance of an aircraft significantly affect its performance, safety, and compliance with regulations. Any inaccuracies in this data could lead to unsafe flight conditions or operational issues. Thus, re-establishing these records by measuring the aircraft ensures that all necessary safety guidelines and operational limits are adhered to.

Other options, such as painting the aircraft a different color or installing a new engine, do not directly contribute to establishing weight and balance records. Estimating dimensions would also not provide reliable data, making accurate weight measurements indispensable for creating valid weight and balance documentation.