What must data used for approving major repairs or alterations be prior to use?

The correct answer necessitates that the data used for approving major repairs or alterations must be GACA-approved. The General Authority of Civil Aviation (GACA) has specific regulations and standards that ensure the safety and airworthiness of civil aviation in the region. Approval from GACA ensures that the data meets the necessary criteria and can be relied upon for making significant modifications or repairs to aircraft.

Using only GACA-approved data ensures compliance with legal and safety requirements, thus protecting the integrity of the aircraft and ensuring the safety of its operations. Other forms of approval, such as internal or manufacturer approval, may not meet the stringent safety and regulatory requirements that GACA mandates, as these standards must align with national and international safety regulations. Additionally, while inspection is a critical step in the repair or alteration process, it is not an indication of whether the underlying data used is formally recognized as accurate and acceptable for the intended changes.