What is the primary purpose of using a protractor in aircraft structural maintenance?

The primary purpose of using a protractor in aircraft structural maintenance is to measure angles. In the context of structural maintenance, ensuring that components are installed at the correct angles is crucial for maintaining the integrity and performance of the aircraft. Accurate angle measurements can affect everything from the fitting of parts to ensuring proper alignment during assembly and repairs. Since aircraft structures often require precise geometric configurations, the protractor serves as an essential tool for technicians to achieve the necessary standards for safety and functionality.

Measuring temperature, surface area, or weight does not directly relate to the critical tasks involved in maintaining structural integrity where angles are a focal point, making the protractor an indispensable tool for those specific maintenance responsibilities.