Environmental Engineering Reference
In-Depth Information
Chapter 10
The potential offered by aircraft
and engine technologies
Jacquetta Lee
1
I
NTRODUCTION
Almost 100 years ago, Orville Wright took to the air at Kitty Hawk, North Carolina,
in the Wright Flyer. Since then, airframes and engines have developed at an amazing
pace. The first gas turbine propulsion system, developed by Whittle and Von Ohain
in the 1930s, has evolved from turbo jets through turbo props to today's high by-pass
ratio engines, and the propulsive efficiency and reliability of the system has improved
enormously. Over the last 40 years alone, the industry has dramatically improved
fuel efficiency and reduced noise and emissions. Engine and airframe weights have
been significantly reduced per passenger kilometre, and safety and reliability have
improved by more than a factor of ten during the last 25 years, allowing the devel-
opment of twin-engine long-range transport with potentially lower associated emis-
sions (Birch, 2000).
While aviation has an impressive record in reducing its environmental impacts,
it faces an interesting future where the environment is likely to play an increasingly
important role. It has been suggested that the predicted growth of 5 per cent per
annum in passenger traffic, and still higher for freight transport, will outstrip the
improvements in fuel consumption, emissions and noise that can be expected through
evolutionary engine and airframe design (IPCC, 1999, p11). Thus, the environmen-
tal burden resulting from air transport is likely to increase. In addition, achieving
further reductions in fuel burn, emissions and noise is also set to become increasingly
difficult as trade-offs between these key impacts become more acute.
The near-term future offers a range of evolutionary solutions for both engine and
airframe; their application depends upon a dialogue with all stakeholders to ensure
that potential improvements do not unduly focus on one aspect to the detriment of
