Who is responsible for in-service weighing of an aircraft?

The operator is responsible for in-service weighing of an aircraft because it falls within their operational and maintenance duties. The operator must ensure that the aircraft's weight and balance are within the specified limits to maintain safety and compliance with regulations. This responsibility encompasses both the initial weighing of the aircraft and periodic re-weighing as necessary, particularly after modifications, repairs, or changes in configuration that might affect the weight.

In-service weighing involves verifying the current weight of the aircraft and assessing how it affects performance, load planning, and fuel consumption. The operator must also keep accurate records of these weights to provide information needed for safety assessments and regulatory compliance.

While pilots, manufacturers, and regulatory authorities have their respective responsibilities, the ongoing management of an aircraft’s weight is specifically under the jurisdiction of the operator. The pilot primarily focuses on flight operation and safety during flights, manufacturers deal with initial specifications and designs, and regulatory authorities set guidelines and standards rather than conducting weight assessments themselves.