Ecological responsibility

For the environment of tomorrow

Acting responsibly with regard to the environment is part of our corporate culture. We are committed to sustainable action toward the environment and future generations.

Harmful emissions from burning kerosine

All the aircraft used in civil aviation today operate entirely on kerosine. As this energy source combusts, it creates carbon dioxide (CO2 ). One ton of kerosine produces 3.15 tons of CO2 as well as water vapour and nitrogen oxide. These gases change the climate, and nitrogen oxide also affects air quality near the ground.

The combustion process of kerosene

The precise composition depends on the operating conditions, cruising height, humidity level and temperature.

Greenhouse gases and pollutants per ton of kerosene: H2O: 1.24t, NOx: 6-20kg, CO2: 3.15t, SO2: 0.7-2.5kg, CO: about 1kg, Soot: 0.1-0.7kg, CxHy: about 0.02 kg
Greenhouse gases and pollutants produced by the combustion of jet fuel.

Fuel dumping

Fuel is dumped in large quantities only if an aircraft has to make an emergency landing shortly after take-off and must therefore drastically reduce its weight. This occurs between once and three times a year and is possible with the Airbus A340 and the Boeing 777 within the SWISS fleet.

Noise emissions

From a technical aspect, aircraft noise is caused by the engines. Hot and cold air meet here at very high speeds. Mechanical processes inside the engine create additional noise. Aerodynamics are responsible for the typical "rushing" sound that occurs as air flows over uneven points on the aircraft.

In aviation, noise pollution on the ground is represented as a noise carpet. The area where the defined limit is exceeded is shaded out. In the past 25 years, the much-affected area around Zurich airport has shrunk by two-thirds even though aircraft movements have almost doubled. Newer, much quieter aircraft have dramatically reduced the number of persons affected by noise.

Visual showing the different noice emission of C Series and conventional aircrafts at Zurich airport.
The C Series is half as loud to the human ear as comparable aircraft types. The overall noise footprint is reduced by an impressive 70 per cent.

Objectives

SWISS takes its responsibility towards the environment extremely seriously, and follows the objectives of the International Civil Aviation Authority IATA. Specifically, they are:

  • By 2020: to improve fuel efficiency by 1.5% annually
  • From 2020: any growth in air travel should be CO2 neutral
  • By 2050: to halve CO2 emissions over 2005

Measures

In order to achieve our targets, SWISS bases its environmental strategy on these four pillars:

Technological progress

New aircraft types produce less CO2.SWISS is continuously investing in a modern fleet. From summer 2016, Bombardier C Series aircraft will be replacing the Avro RJ 100 fleet on short and medium haul. Between 2019 and 2022, SWISS will be adding ten of the latest generation Airbus A320neos and five Airbus A321neos to its fleet to replace ten older Airbus A320s and five Airbus A321s. On long haul, six Boeing 777s will replace the Airbus A340 in 2016. Three further Boeing 777-300ER aircraft will be joining the SWISS fleet in 2017 and 2018.

Operational measures

The more efficient a flying process is, the less of a burden it is on the environment. For instance, high-performance flight management systems can help to better utilise high-altitude winds. Systematic loading provides the optimum aerodynamics. And when the situation allows, SWISS pilots on the Airbus A340 switch off two of the four engines after landing and taxi to their stand position on the two remaining engines.

Efficient infrastructures

Better utilisation of airspace, airports and flight safety can help to significantly reduce CO2 emissions from aviation. Unfortunately, airways are only rarely efficient because each country controls its own airspace individually. The European Commission wants to intervene here. The project "Single European Sky" would help to save up to 10 million tons of CO2 every year – enough fuel to keep the entire SWISS fleet flying for three years.SWISS is involved in various studies in support of the Single European Sky Air Traffic Management project initiated by the European Union.

Economic instruments

SWISS is committed to a global and fair system for treating aviation emissions. This system rewards active environmental care and facilitates fair global competition. Furthermore, every SWISS passenger can commit to individual voluntary compensation for the CO2 emissions they cause through "myclimate".

CO2 emissions and kerosene consumption

SWISS has greatly reduced its specific CO2 emissions since 2003. Today the figure is just under 20% less per 100 passenger kilometres. In order to achieve this goal, SWISS has invested billions in new aircraft types, used lighter materials, and improved flight processes and its flight loads.

Noise emissions

In aviation, noise pollution on the ground is represented as a noise carpet. The area where the defined limit is exceeded is shaded out. In the past 25 years, the much-affected area around Zurich airport has shrunk by two-thirds even though aircraft movements have almost doubled. Newer, much quieter aircraft have dramatically reduced the number of persons affected by noise.

Visual showing the different noice emission of C Series and conventional aircrafts at Zurich airport.
The C Series is half as loud to the human ear as comparable aircraft types. The overall noise footprint is reduced by an impressive 70 per cent.