No abstract

The present work describes an airliner design platform that has been developed over several years and its application to design airliners based on an efficiency index developed by the authors of the present work. Among other characteristics, the design tool can handle airplane geometries with detail and count on a unique and accurate neural network system to predict aerodynamic coefficients. A new feature for product classification was incorporated into the framework. It is based on entropy statistics and was calibrated for jet transport airplanes and the results of classification are analyzed in the present work. The design of a Middle of Market airplane was then carried out with the classification provided by entropy statistics set as a constraint. Middle of the Market is a term that was established to address the commercial aircraft market segment that encompasses long-haul sectors from 3500 nm to 5000 nm, and airplanes with single-class passenger capacity between 220 and 250. Until now, this segment was not extensively explored, and some airlines have been showing interest to purchase airplanes better suited to it = this category. Multi-objective optimizations were carried out to determine the best aircraft design that fits into this concept's range and capacity specifications. The unsupervised learning algorithm based on entropy statistics was applied for airplane classification into four labels, classic, niche, failure, and breakthrough designs. A higher fidelity engine model optimization task was also carried out to search for optimal classic designs. In addition, a robust optimization considering a fuel price variation on Direct Operating Cost was carried out. All results raised an important discussion about the benefits and drawbacks of a trijet configuration for transport airplanes with a capacity of over 200 passengers.