Comparison of Structural Weight Efficiency and Local Strength Between Cylindrical and Blended-Wing-Body Fuselages: An Analysis Based on Public Data from Three Aircraft Types

Abstract

The continuous pursuit of higher aerodynamic efficiency in modern civil aircraft has driven the exploration of new layout configurations. This paper compares the weight and strength of two configurations: the conventional cylindrical fuselage and the blended-wing-body. Taking the Boeing 737-800, Airbus A350-900, and NASA X-48B testbed as research samples, this study establishes unified comparison conditions by extracting the main structural parameters and material strength data of the three aircraft. Methodologically, this paper combines theoretical structural-mechanics analysis with normalized comparisons of published aircraft and simulation data under static, dynamic, and failure criteria. The core results show that the blended-wing-body has a significant advantage in structural weight, but it is inferior to the cylindrical fuselage in terms of local strength and fatigue life. Most of the percentages quoted in this paper were worked out from published figures for the three sample aircraft. They are not test data. The three types were designed to different requirements, and the manufacturers do not release the same level of detail, so the values are useful for comparing trends and should not be read as exact. On the whole the blended-wing-body comes out ahead in aerodynamic efficiency and in how much of the internal volume can actually be used; reliability and maintainability are where it still lags behind the cylindrical fuselage. A segmented blended configuration, possibly combined with smart materials to relieve the local stress problem, is one direction for later designs. The figures here may be of some use when a structural layout has to be chosen early in a project.