Sensitivity Factors of Aircraft Mass for the Conceptual Design

Purpose – The purpose of this work is to further develop the methodology for calculating the aircraft take-off-mass and its main functional components for the conceptual analysis and synthesis of new projects.

Design/methodology/approach – The method is based on the assessment of changes in the take-off gross mass (TOGM) of the already developed project or already existing a basic version of the aircraft when making local mass changes for its modification or for the numerical researches to create a more advanced project. The method is based on the "Sensitivity factors of mass" (SFM) of aircraft, which represents the ratio of TOGM to initial (local) mass changes of its main functional components. The method of analytical refined calculation of SFM for the initial mass change and the main aerodynamic characteristics is given.

Findings – In comparison with the long-known method based on weight (mass) growth factors, which were considered constant, this method takes into account the dependence from the value of the initial local mass change and its functional purpose.

Practical implications – This method allows the designer to calculate more strictly the final changes in the TOGM on the initial stages of conceptual design when finding new project solutions. Numerical calculations are given on the example of passenger aircraft. The dependence of SFM, and TOGM and its functional masses on the value of the initial change of the structure mass is shown.

Originality/value – The considered method based on SFM is simple and convenient, and more accurate for conducting project research on many project parameters when analyzing and synthesizing a new project.