The main goal of this paper is to present a vision for the future of aviation. Developing such a vision is always a complex matter, but in times of environmental emergencies and unjustifiable wars it becomes even more difficult. One of the main reasons of this paper is to show that there is still room for advancing clean technology developments and to demonstrate that the aviation sector is ready for embarking on new challenge.

Green and environmentally sustainable aviation, in our opinion, can be achieved with continuous improvements along multiple parallel paths, ramp up of SAF (Sustainable Aviation Fuel) production, and of course, breakthrough technologies. The latter will require a significant amount of research, testing and probably mistakes need to be made before reaching the level of transportation efficiency and mission safety obtained with traditional propulsion, but these drawbacks should only encourage scientists, engineers, politicians and visionaries to strongly pursue the objectives of a new eco-aviation.

Aviation decarbonization requires a strategy change from near term improvements in aircraft fuel efficiency to long term (from neutral to zero carbon emissions) fuel switching. The successful introduction of long-term solutions requires transdisciplinary research into technological, operational and economy fields.

New technologies should probably be introduced into smaller aircraft segments first then migrate into the larger segments as the technologies mature. We should expect a first electric and hydrogen fuel cell commuter aircraft entry into service by the end of this decade, with hydrogen combustion-powered narrow bodies around 2040.

In 2019, aviation accounted for approximately 2.3% of global greenhouse gas emissions, with global commercial fleet CO₂ emissions totaling 0.918 Gigatonnes. Narrowbody and widebody aircraft produce over 95% of the industry's greenhouse gas emissions, therefore, while the introduction of new technologies on smaller aircraft will be important for the development of sustainable solutions, they will have minimal impact on the overall carbon footprint until they make their way onto larger platforms. However, carbon-free fueled (electric, hydrogen) aircraft will require significant infrastructure investments to develop the novel transportation network and the re-fueling procedures that will be required to support their use. Therefore, their success will require the coordinated combined efforts of the entire industry (airlines, airports, air navigation service providers, manufacturers) and significant government support.

This paper tries to summarize the most important aspects for a vision on sustainable green aviation and to indicate a possible roadmap for reaching this goal.

本文的主要目标是提出航空未来的愿景。制定这样的愿景始终是一件复杂的事情，但在环境紧急情况和不合理的战争时期，它变得更加困难。本文的主要原因之一是表明清洁技术发展仍有推进空间，并表明航空业已准备好迎接新的挑战。

我们认为，绿色和环境可持续航空可以通过沿着多个并行路径不断改进、提高 SAF（可持续航空燃料）产量，当然还有突破性技术来实现。后者需要大量的研究、测试，并且可能需要犯一些错误，才能达到传统推进的运输效率和任务安全水平，但这些缺点只会鼓励科学家、工程师、政治家和有远见的人强烈追求这一目标。新型生态航空的目标。

航空脱碳需要战略转变，从近期提高飞机燃油效率转向长期（从中性到零碳排放）燃料转换。成功引入长期解决方案需要对技术、运营和经济领域进行跨学科研究。

新技术可能应该首先引入较小的飞机部分，然后随着技术的成熟迁移到较大的部分。我们预计第一架电动和氢燃料电池通勤飞机将在本十年末投入使用，氢燃料驱动的窄体飞机将在 2040 年左右投入使用。

2019年，航空业约占全球温室气体排放量的2.3%，其中全球商业机队CO ₂排放总量为 0.918 十亿吨。窄体和宽体飞机产生了超过 95% 的行业温室气体排放，因此，虽然在小型飞机上引入新技术对于可持续解决方案的开发非常重要，但它们对整体碳足迹的影响微乎其微，直到它们真正发挥作用。进入更大的平台。然而，无碳燃料（电动、氢）飞机将需要大量基础设施投资来开发新型运输网络以及支持其使用所需的加油程序。因此，它们的成功需要整个行业（航空公司、机场、空中导航服务提供商、制造商）的协调一致努力以及政府的大力支持。

本文试图总结可持续绿色航空愿景的最重要方面，并指出实现这一目标的可能路线图。