1 Rarely, fistulas occur externally to the skin or internally to another part of the biliary tree, to the pleural cavity or bronchial tree, or to the hepatic artery or portal vein or other vascular structures.
Load factor (aeronautics) In aeronautics, the load factor is defined as the ratio of the lift of an aircraft to its weight and represents a global measure of the stress (load) to which the structure of the aircraft is subjected: where: Since the load factor is the ratio of two forces, it is dimensionless.
Aerodynamics first: The altitude factor of $c_l \cdot Ma^2$ tells you how much lift can be produced at a given flight Mach number, and the wing loading then gives you the minimum density for sustained flight. 0.4 is a good value for $c_l \cdot Ma^2$, and 30 kg/m$^2$ is a feasible wing loading for flight at 30 km.