Europe Moves To Better Understand Supersonic Aircraft Impacts
Europe has launched a research program to develop a deeper understanding of the environmental impact of future supersonic aircraft and provide input into international efforts to develop certification standards for noise and emissions.
The four-year, €5 million ($6 million) Seneca project (for Noise and Emissions of Supersonic Aircraft) was launched in January and involves 11 European academic and industry participants led by German aerospace center DLR.
The project is focused on detailed modeling of the landing and takeoff (LTO) noise, emissions and global environmental impact of supersonic aircraft. Project results will provide inputs to meetings of the International Civil Aviation Organization’s Committee on Aviation Environmental Protection in 2022 and 2025 that will recommend certification standards.
Seneca will develop models for four different aircraft platforms: 10-seat business jets with cruise speeds of Mach 1.4 and Mach 1.6 and 100-seat airliners cruising at Mach 1.8 and Mach 2.2. The study assumes that the first of the new generation of aircraft will fly supersonic over water only, to avoid generating sonic booms over land.
The project will involve multidisciplinary optimization (MDO) of the four designs, with the goal of ensuring they can meet at least the current noise regulations for subsonic aircraft during takeoff and landing. A second goal is to minimize emissions. The modeling level of detail will be adequate to forecast certification levels and aircraft performance.
Seneca will investigate the impact of engine technologies, such as two-stage fans and variable-area nozzles and/or inlets, on aircraft performance and noise. The study will also evaluate the potential of variable noise reduction systems, such as automated thrust reduction during takeoff, on emissions and LTO noise.
The project will provide LTO noise certification levels for the four different aircraft, as well as fuel burn, CO2 emissions and engine emission indices for nitrogen oxides, carbon monoxide, sulfur oxides, unburned hydrocarbons and soot.
Supersonic platforms will cruise at higher altitudes than subsonic aircraft, so Seneca will also quantify a range of climate impacts from supersonic aviation through numerical simulations using models of atmospheric chemistry, climate response and contrails.
A goal of the study is to deliver trade-offs between noise, emissions and climate impact, against each other and with flight range, and show their dependency on parameters such as engine bypass ratio. The trade-offs will provide insight into how noise regulations, for example, affect CO2 and other emissions.
A companion European research project, More&Less (for MDO and Regulations for Low-boom and Environmentally Sustainable Supersonic Aviation), will develop an integrated multidisciplinary modeling framework to determine how different aircraft shapes affect the intensity of sonic booms. The four-year, €6.3 million project is led by Turin Polytechnic.