Abstract Environment protection is now considered as a key point by the population and has become a political and economical stake as related in Kyoto protocol signature which defines objectives for greenhouse effect gases reduction. Based on greenhouse effect gases like carbon dioxide (CO2) and increasing temperature, European Union has implemented an Emission Trading System to give each country emission CO2 targets and a trade tool to share tons of CO2. The European Union has fixed specific objectives to aeronautic section via the Advisory Council for Aviation Research and innovation in Europe. Helicopter community is implementing qualitative tools called environmental metrics to measure the achieved progress. Environmental acoustic metrics have been defined based on noise levels and colors, related to ICAO limitation levels and in the frame of European research project Cleansky. Similarly, environmental metrics for CO2 emission have also been defined based on fuel consumption values and colors. The more the helicopter is environment friendly, the greener the metric. In anticipation of environmental requirements strengthening, some helicopter manufacturers have launched research studies on environmental technologies like Friendcopter project to develop low acoustic level flight procedures based on HELENA computations, or engine manufacturers have invested in technological research projects to improve engine performance and environment impact. In addition, the helicopter product full life cycle is globally considered under the international standard ISO 14001 for environment management as well as human health and environment protection in comparison to REACH European regulation. The reader of the article will certainly notice that the challenge is now: “Towards greener helicopters”.