Commercial aviation, faced with worldwide concerns about greenhouse gases and looming regulations to reduce them, can count on advances in technology that will help to clean up its operations to a substantial degree during the coming 20 years. But growth in air travel, both an enabler and a product of the burgeoning global economy, is likely to use up the environmental gains faster than they can be achieved.
The gains will come from aircraft and engine designers, particularly the latter, as they create and produce the next generations of commercial aircraft -- the Airbus A380 and the Boeing 787, both scheduled to enter service within a year; the A350, Airbus's forthcoming answer to the 787, which will lag by several years; and the airframe manufacturer's successors to their current single-aisle families, which probably won't reach airlines before the late 20-teens or the early 2020s.
Equally important to greenhouse-gas reduction, major improvements in air traffic management are in advanced stages of planning and early stages of development. The U.S. NextGen satellite-based air traffic management system, Europe's comparable Sesar ATM research program and adaptations worldwide are intended to increase the capacity of airspace systems to match the growth projected for aviation in the coming decades. In doing so, the ATM upgrades will, in many cases, shorten flight times.
Each of these initiatives will reduce the emission of greenhouse gases, because each will save fuel. In every case the driver is economic. Reducing fuel consumption cuts airline costs, an important goal at any time and a crucial one as oil prices continue to increase and fuel succeeds personnel as the highest cost category at most airlines. The moderation and stabilization of oil prices -- so optimistically predicted last winter -- hasn't happened. Indeed, they reached record highs this summer.
Although work to reduce fuel consumption is intended to boost airlines' bottom lines and the ATM initiatives grew out of the need to increase the capacity of national and regional airspace and airports, the environmental benefits of both promise to be enormous. The principal greenhouse gas produced from aircraft operations is carbon dioxide, and the weight of CO2 emissions from aircraft is considerably greater than the weight of the aviation fuel that creates them during combustion. Estimates from think tanks, academics, trade groups and individual companies suggest that unit fuel-burn reductions well into double-digit percentages can be attained in the coming 10-20 years from each of these two avenues.
The trouble for aviation is that growth in passenger and cargo traffic is likely to swallow up these unit reductions and cause an overall increase in CO2 tonnage during this same time frame.
Last winter, in its annual long-range forecast of U.S. airline activity, the FAA projected a 47.3% increase, to 5,750, in the number of mainline aircraft in the U.S. passenger fleet between 2005-20, reflecting 3% average annual growth. The increase among mainline-size cargo aircraft is similar in scale -- 48.1%, to 1,468, at 2.8% per year.