Aviation needs to bring its CO2 emissions down to zero not far beyond 2050. To achieve this, a wide range of technologies and policies is considered. Among these are taxes, ban on short flights, faster trains, electric planes, zero-carbon fuel and enhanced energy efficiency of aircraft and operations. For policy development and for investment decisions, it is useful to have insight into the impact of alternative approaches. The table below assesses the three most important consequences of different policies: CO2 emissions, ticket price and travel volume. This gives a first comparative overview. The data are estimates, based on uncertain assumptions (see paper). This assessment is not intended as final answer, instead as a kick-off for discussion and improvements. Despite its limitations, the overview shows that sustainable fuels will have a large role in decarbonizing aviation.