Graham Warwick/SYDNEY Julian Moxon/PARIS

The international panel tasked with defining new, tougher noise limits for commercial aircraft is analysing the environmental benefit and economic impact of a range of increasingly stringent options ahead of a key meeting in September.

The International Civil Aviation Organisation's (ICAO) Civil Aviation Environmental Panel (CAEP) has developed a matrix of options based around cumulative noise levels of 8, 11 or 14dB below current Chapter 3 limits.

The least onerous options would require only new aircraft types certificated from 2002 to meet the new noise limits. More stringent options would require the phasing out of in-service aircraft not meeting the new limits by 2020 at the latest.

Phase-out options being studied range from requiring all aircraft to meet the -8dB level by 2020, to requiring all in-service aircraft to meet a -5dB limit by 2006 and an -11dB level by 2013.

The CAEP steering committee is due to meet in September to narrow the options to a shortlist to be considered by the full CAEP meeting in January. The panel is expected to recommend one option for adoption by the ICAO Assembly in September 2001 as the new global noise standard.

All modern Airbus and Boeing aircraft meet the -5dB limit and most can meet the -8dB level, says an International Air Transport Association (IATA) official familiar with the CAEP deliberations. "At -11dB it starts to get tougher and the fleet starts to take a hit. At -14dB there is a significant impact as neither Airbus nor Boeing can offer a full family of aircraft sizes meeting the limit."

In IATA's view, there is no single option that all states will accept, and it fears the CAEP process will become deadlocked, causing a breakdown in global noise standards. As a result, IATA plans to draw up alternative proposals to present to CAEP in September.

"IATA supports increased stringency, but not a mandatory phase-out," the official says. "It should be left to the market to determine the phase-out." Ideas being looked at by IATA include requiring manufacturers to buy back and scrap one old, noisy aircraft for every two new, quiet aircraft sold and classifying airports according to their noise sensitivity.

Meanwhile, the European Parliament is being encouraged to support a proposal under which the European Union (EU) would act unilaterally to strengthen noise standards if ICAO fails to agree its own measures.

A recent draft report prepared for the Parliament on a European Commission (EC) study on air transport and the environment says "the ICAO process of revising noise stringency levels may not meet the particular needs of the densely populated, industrialised EU". It calls upon the commission to pursue "complementary measures to be implemented if ICAO cannot reach appropriate agreement".

This reflects the EC's proposal for action on noise if the ICAO meeting fails and hints at a repeat of the controversial action taken by the EU banning hushkits.

Source: Flight International