Manufacturers anticipate new environmental regulation

Aircraft manufacturers expect soot particles and contrails to become the next targets of environmental protection legislation.

Speaking at the first global Aviation & Environment Summit in Geneva this month, CFM International vice-president for marketing Pierre Bry said engine manufacturers are considering studying the reduction of ultra-fine particulates – residue from partially burned fuel – from powerplant emissions because of concern that they could be carcinogenic.

Assad Kotaite, president of the International Civil Aviation Organisation council, said controls on water vapour emissions are also being mooted around the world.

Bry said: "Particles will be the big story in time to come, but they are not even measured yet, so it's too early for us to talk about." Current legislation addresses smoke emission, but does not stipulate the size of particles.

Fine particulate emissions from aircraft have become an increasing concern in the USA in recent years because they are identified as lowering local air quality, rather than contributing to wider environmental concerns. Incomplete combustion of hydrocarbon fuel in gas turbine engines produces small particles, comprised mostly of solid carbon as soot. Engine erosion and trace metal impurities in jet fuel create metal particles that are emitted in the engine exhaust.

The US Federal Aviation Administration, Transport Canada, NASA and other bodies have launched studies into particulate emissions – seen as the first step to eventual regulation.

A source at Chevron-Texaco says the US Environmental Protection Agency is particularly concerned about particles smaller than 2.5µm, adding that fuel suppliers are "looking into the combustion chemistry to see what can be eliminated through refining". In August last year, NASA and the US Department of Defense undertook a comprehensive test on particle emissions with the Aircraft Particle Emissions Experiment (APEX) project using a McDonnell Douglas DC-8-70 powered by CFM International CFM56 engines.

Industry is also concerned about water vapour emissions, with Eurocontrol saying several green lobby groups are already hinting at controls.

Eurocontrol is launching a study with the European Space Agency to use satellites for measuring contrail formations, to provide solid data on which to base any legislation proposals.

JUSTIN WASTNAGE/GENEVA

Source: Flight International