What factor does NOT play a role in the bend allowance calculation?

The factor that does not play a role in the bend allowance calculation is the material type. Bend allowance calculations focus primarily on how the material behaves during bending, which is influenced by the radius of the bend, the angle of the bend, and the thickness of the material.

The radius of the bend and the angle of the bend directly affect how much material is stretched and therefore contribute significantly to determining the allowance needed for the bend. Likewise, the thickness of the material influences how much stretch occurs in the material once it's bent.

While different materials can have varying properties and behaviors (such as elasticity or ductility), which could indirectly affect the bending process, the fundamental calculations for bend allowance do not incorporate the material type as a direct factor. Instead, the calculations rely on geometric relationships and dimensions to accurately determine the required bend allowance for the construction and design of aircraft structures.