In previous sections, we have seen that there are various projects of aviation sustainability and we have analyzed the perspectives of these projects. While we found growing networks, we recognized that the driving forces from markets are within the limits of expectation on cost-efficiency. Besides of these facts, we must note the IATA’s report, which warns that even we implement all of the technology and operational innovations (a) lighter weight, (b) low air resistance aircraft design, (c) lean combustion and a high bypass engine, (d) an optimized electric system and (e) optimized flight routes), it is not achievable to bring aviaFigure 1. Schematic roadmap of aviation CO2 emissions under the effect of reduction measures (Adapted from IATA, 2009)
2005 2020 2050
tion to CO2 carbon neutral emissions (Figure 1). “Regime” changing innovations are expected for “Carbon Neutral Growth from 2020”. We need to discuss how to manage a radical technology or system change. And we think it is important to understand the driving force in the aviation socio-technical system in multi-level perspectives.
Multi-Level Perspectives (MLP) is a useful approach to understanding transition pathways of an innovative idea to integrate in the main stream of a system or a society. It comes from SNM researches and has a complementary relationship with SNM (Schot & Geel, 2008). The MLP distinguishes three levels (niche, regime and landscape) in a system. Niches are a level of emerging innovations and are situated at the margin of the regime. Regimes are a level of the main or existing streams and create stability of the system. Landscapes are the macro-level of society as a whole. The interplay between dynamics at multiple levels leads transitions. See Geels (2006) for further explication. In brief, Geels concluded that co-evolution at the regime level was clearly visible in his case studies of past technology or system replacements. There was a strong interaction between technology and markets. Transitions are not caused by a change in a single aspect, but by the interplay of many aspects and actors.
A MLP approach may help Green’s (2002,
2006) radical idea of flight with short-range aircraft with several refuelings before arriving at their destination. A lot of technical papers and significant benefit have been proposed, but this idea doesn’t appear in a roadmap of this sector. Green’s idea is against the development of long - range aircraft, or of aircraft technology itself. The development of longer-range flights is often described in the first slides of manufacturers and airline presentations. For example, development of aircraft technology reduced the number of stops of the London-Sydney flight from 32 stops and 10 days in 1939 by Flying Boat, 2 stops and 26 hours in 1990 by 747-400 to 0 stops and 19.5 hours in 2006 by 777-200LR, according to Qan - tas. But according to Green, using an aircraft of 5000km range capacity with stops of lubrications at airports can be about 40% more fuel efficient than carrying the same number of passengers along a 15000km distance using an aircraft of 15000km range capacity. This difference is due to the weight of fuel, which covers all of the flight. In other words, for carrying fuels, a long distance flight consumes nearly half of the fuel. Green’s short-range aircraft idea is an effective solution for the reduction of CO2 emissions, but it is considered unrealistic. Customers will not accept the trouble of stopping in several airports once they have taken a non-stop flight. Although there is the idea of air-to-air refuelling, this type of refuelling is risky in terms of safety. For such a socially challenging issues, MLP approach will be useful to list the problems to solve and organize the learning process.
Some of MLP researchers study the interaction of different niches or regimes. There are several options for the future aviation system. Many stakeholders wish aviation for sustainability. On the other hand, there are some options that may go opposite direction of “sustainability”. Supersonic transportation attracts some of airlines and business travellers. Cohen (2010) detected the small but strong human desires for personal aeromobility pushing back the force for sustainability. Each innovative aviation scenario including “sustainability” has opposite and favourable driving forces and may not able to be realized by itself. If we could combine the favourable driving forces, we might be able to obtain sustainability and even further ideals for the sector. For example, we may be able to load low-carbon technologies on personal aircraft in the same way as Toyota obtained technology and cost supremacy in the hybrid engine mark by mounting the hybrid engine in the compact size car and pursuing low profit but high volume. Even though the requirements for safety and security will not change between small and large aircraft, small aircraft might have advantages in terms of the difficulty of development because of the strength and complexities of the system as well as the scale of the market. Manufacturers may be able to innovate their technology development from small aircraft, which has fewer constraints, and transform these technological developments in big aircraft much earlier than in direct development to big aircraft. Therefore, we propose management ofthe sector’s future options in multi-level perspectives as a future research directions for sustainable aviation.