What is the definition of the buttock line in aircraft terminology?

The buttock line in aircraft terminology refers to a measurement that is taken left or right of the aircraft's vertical centerline, running parallel to it. This line is particularly important in the design and analysis of the airframe as it helps in assessing the geometry of the fuselage and other structural components. By providing a reference for lateral positioning, buttock lines assist in ensuring that all components are aligned properly and symmetrically, which is crucial for maintaining the aircraft's aerodynamic properties and structural integrity.

Understanding buttock lines is essential for engineers and technicians as they aid in the inspection and modification of aircraft structures, ensuring that any alterations do not disrupt the balance and performance of the aircraft. The significance of this measurement can be seen in the context of aircraft assembly, where precise alignment is critical for safety and operational efficiency.