ECONOMIC-PARAMETERS IN THE CONCEPTUAL DESIGN OPTIMIZATION OF AN AIR-TAXI AIRCRAFT

A new methodology for the conceptual design optimization of a public t ransport vehicle for a specific network is proposed, in which the impo rtance that the passengers assign to their time is incorporated as a p arameter called value of time V. A penalty function P is developed, wh ich is a combination of the fare, the time spent in travel, and a comf ort factor. For operation over virgin areas, the sizing of the transpo rt termini and estimation of the costs associated with their construct ion is an intrinsic part of the vehicle optimization studies. As an ex ample, this methodology is integrated in the conceptual design of twin -engined pistonprop and turboprop general aviation aircraft to be empl oyed for air-taxi operations over a hypothetical network. The optimum location of the airport from the city center, and the minimum runway l ength required for safe operation is determined. The costs associated with construction and maintenance of a runway at each node of tile net work C-rw are estimated and charged to the passengers as a part of the ir fare. A set of eight aircraft related parameters (design variables) that correspond to the minimum P is obtained, while assigning nominal values to tile remaining parameters. Eight test-cases are investigate d and the sensitivity of P to the design variables is determined. It i s found that the aircraft capacity and the cruising speed are directly dependent on tile V, and the inclusion of C-rw in P tends to drive th e optimum towards lower cruising speed. In all the cases studied, turb oprop aircraft show a lower P compared to the pistonprop type.