Environmental Engineering Reference
In-Depth Information
needed to evacuate the aircraft in an emergency and how passengers would take to
flying in an aircraft with no windows.
C ONCLUSION
It is clear that the conventional airframe/engine configuration can offer reduced
environmental impacts, even where these impacts appear to be in conflict with one
another. However, it is also clear that in the long term, alternatives to this configura-
tion need to be carefully evaluated. For example, a blended wing body, fuelled by
hydrogen, with engines mounted on the top side and with hybrid laminar flow,
could represent the ultimate technological solution. The key to continued air trans-
port is, of course, an integrated system incorporating many of the concepts given
here, alongside non-technical options such as planning and operational issues.
The decision as to which technologies are finally developed rests on the market,
and includes legislative bodies, non-governmental organizations (NGOs), technol-
ogy developments and, perhaps most importantly, the concerns of the public who
ultimately decide what they want, and do not want, through consumer spending power
and votes. While, at the current time, it is hard to envisage a world in which environ-
mentally benign transport is the only acceptable form of transport, the aviation indus-
try must be ready to face this challenge should the need arise.
N OTES
1
It should be recognized that the views expressed in this chapter are those of the author
and do not necessarily represent the policy of Rolls-Royce plc.
2
Laminar flow is an expression used to describe air flowing smoothly over a surface (eg a
wing). It usually refers to the flow close to the surface, known as the boundary layer. When
the flow is smooth, the boundary layer is said to be laminar. The opposite is a turbulent
boundary layer, where the flow is of an irregular, eddying nature. Friction between the
surface and the moving air is much greater when the boundary layer is turbulent. (Shev-
ell, 1989, p167; Allen, 1982, p136).
3
Stoichiometric temperature is the temperature resulting from the combustion of a fuel/
air mix at a ratio where all the oxygen is consumed.
R EFERENCES
Aeronautique, Astronautique (1998) Proceedings of the 3rd Aerodays , Toulouse, 27-30 Octo-
ber 1997
Air Transport Action Group (ATAG) (1999) Aviation and the Environment, ATAG, Geneva
Allen, J E (1982) Aerodynamics: The Science of Air in Motion , second edition, McGraw-Hill,
New York
Beesley, C (2000) The Impact of Product Stewardship on Materials Selection, ICETS, Beijing,
July 2000
Birch, N (2000) '2020 Vision: The Prospects for Large Civil Aircraft Propulsion', The Aero-
nautical Journal , volume 104, no 1038, August, pp347-352
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