Adaptable conceptual aircraft design model
Advances in aircraft and spacecraft science
This paper presents a new conceptual design model ACAD (Adaptable Conceptual Aircraft Design), which differs from the other models due to its considerable adaptability to the different classes of aircraft. Another significant feature is the simplicity of the process which leads to the preliminary design outputs and also allowing a substantial autonomy in design choices. The model performs the aircraft design in terms of total weight, weight of aircraft subsystems, airplane and engine
... d engine performances, and basic aircraft configuration layout. Optimization processes were implemented to calculate the wing aspect ratio and to perform the design requirements fulfillment. In order to evaluate the model outcomes, different test cases are presented: a STOL ultralight airplane, a new commuter with open-rotor engines and a last generation fighter. Two-seat Short Takeoff and Landing (STOL) Ultralight Aircraft. The main requirement for this test case is the maximum take-off weight (W MTO ) which must not be greater than 450 Kg due to airworthiness regulations. For this aircraft category, the weight limit differs for each country, due to the lack of common regulations. Consequently the strictest one is considered in this study. Moreover, given the STOL requirement, the ultralight can operate from very short length airfields (about 100 meters). Fast and Green Regional Aircraft. This aircraft has to carry 90 passengers for short-haul flights. The fuel consumption has to be similar to regional turboprop, but the cruise speed (V CR ) must be greater (at least 800km/h). Considering these requirements this new regional aircraft is equipped with Prop-Fan engines (McDonald et al. 2008 , Lee et al. 2009 ). Fifth Generation Fighter. This is a valuable test case, as it includes all model features. The payload weight (W PL ) and combat radius requirements, which are respectively 1200 kg of weapons and 1200 km, classify that airplane as a light fighter. It should be a new segment of this class of fighter since the others, which are already flying, such as Lockheed Martin F-22, F-35 and Sukhoi PAK FA, have greater weapon weight and radius which means a greater W MTO (respectively of 38, 32 and 37 tons). Combat turn and super cruise requirements are also considered in the conceptual design process. These test cases were selected in order to emphasize the ACAD model flexibility. As it is possible to understand from their descriptions, they notably differ in terms of W MTO , V CR , mission profile, configuration, wing loading, class of propulsion system and basically all the remaining airplane characteristics. The present work starts with the description of the test case design requirements and the analysis of the model design process. Then it continues with the examination of the aspect ratio optimization subroutine and the matching chart subroutine necessary to verify the design requirements fulfillment. Finally, the test case results are analyzed.