In inspecting a major alteration, what must the holder of an inspection authorization determine regarding the data used?

In the context of inspecting a major alteration, it is crucial for the holder of an inspection authorization to determine that the data used is compatible with other installations. This is vital because alterations may impact existing systems, structures, or components, and ensuring compatibility helps maintain the safety and airworthiness of the aircraft.

Compatibility assessments involve verifying that the alterations do not adversely affect the performance or functionality of related systems. It may include examining how the new installation interacts with existing equipment and whether it adheres to any relevant design, engineering, or certification standards.

While other factors, such as compliance with original specifications or acceptability to the Administrator or manufacturer, are also significant, the primary focus during the inspection process should be on ensuring that the new alteration integrates seamlessly with the current system architecture. This step is essential for ensuring the overall integrity and operational safety of the aircraft after the modification.