سر و صدا و نشر هدف قرار داده شده اقتصادی تجارت کردن برای نسل بعدی هواپیمای تک راهرو

A methodology focusing on the evaluation of noise and emission specific direct operating cost components for future aircraft concepts is presented and applied to compare a geared turbofan versus an open rotor powered single-aisle aircraft. High uncertainties in the future development of airline environmental regulations, restrictions and charges complicate the noise and emission related evaluation of new aircraft. The implementation concept is based on the combination of classical procedures for economic aircraft evaluation with scenario techniques.

Whereas aircraft noise and local air quality associated with air transport have been regulated for many years, CO2 emissions are in the process of standard development and regulation. Noise related airport charges are increasingly widespread and supplementary landing charges for gaseous emissions have already been established in Germany, Switzerland, Sweden, UK and elsewhere, measuring local air quality in terms of NOx and HC emissions. The integration of aircraft CO2 emissions in the EU emissions trading system only came into effect in 2012. The challenge is that there may be conflicts when trying to limit noise and gaseous emissions at the same time, as well as for the optimal development of both policies. Although open rotor engines will likely produce significant fuel savings, noise levels are unlikely to be reduced compared to current turbofan powered aircraft. In addition to the technical issues, there are economic considerations, and while it may be, for example, economically viable to reduce one environmental impact it may involve heavy expenditures to contain the other. This paper evaluates the merits of alternative aircraft with regard to noise and CO2 emissions looking at two future aircraft concepts using geared turbofans (GTF) and open rotor (OR) engines.

Aircraft design often requires trade-offs, and this becomes apparent in our case study of noise and CO2 emissions. Technical comparisons are difficult, however, because of potentially different basis of comparisons not only in terms of the baselines to be drawn, such as assumed flight lengths and payloads, but also in terms of assumptions about future costs of inputs, such as aviation fuel. Thus, although the open rotor aircraft concept may provide up to 9% higher fuel efficiency compared to a geared turbofan aircraft, the former fuel economy benefits may be off-set because of greater noise levels and potential higher costs of aircraft ownership. Thus, depending on the scenario regarding fuel prices and regulations on more stringent noise restrictions and curfews, the outcome can vary.