Environmental Engineering Reference
In-Depth Information
September 2001, ICAO agreed new and more stringent Chapter 4 requirements
that would be applied to aircraft certified for introduction after 1 January 2006.
Currently, all Chapter 2 aircraft must be phased out not later than 1 April 2002
(completed in the US at the end of 1999). After this date, Chapter 2 aircraft will have
to be retired or recertificated to meet the Chapter 3 requirements. In recognition of the
particular social and economic conditions in developing nations, derogations were
made for certain aircraft to be allowed to continue operating. ICAO did not, however,
adopt a phase-out programme for Chapter 3 aircraft. It chose, instead, to call for the
adoption of what it termed a 'balanced approach' to dealing with the issue of aircraft
noise disturbance, involving reduction in noise at source, land-use planning, opera-
tional constraints and noise-abatement procedures.
ICAO is responsible to all the UN member states and has to act in accordance
with their wishes. The speed with which ICAO certification regulation moves for-
ward, the level of increased stringency adopted at each stage and the inclusion of a
provision for the phase-out of existing aircraft result from the resolution of the fol-
lowing significant and sometimes conflicting pressures.
The environmental perspective
The rate of the development and introduction of improved aircraft noise technology
should be fast enough to offset the effects of growth in air transport. Even this will
be a minimum requirement as sensitivity to disturbance increases.
The manufacturers' perspective
Noise certification standards have to reflect what can be achieved in technological
terms. Progress in developing quieter aircraft is becoming more difficult and more
expensive to achieve, and this will affect the rate at which aircraft are introduced
into the airline fleet.
The airline perspective
Airlines continue to invest in very expensive aircraft that can be forced out of service
by phase-out requirements, thereby reducing the operational life of their fleet and,
hence, the value of the company.
The economic and social implications for different countries
Countries and the airports within them differ significantly in terms of traffic levels,
number of people exposed to noise, need for air transport growth and levels of per-
ceived opposition to noise in local communities. In some regions, especially remote
and island communities, aviation has a particularly important role to play. In others,
maintaining and developing air routes to key cities are critical to national economic
development. National governments will also take account of the interests of their
airlines, airports and aircraft manufacturers.
