United States adopts ICAO Chapter 14 noise stringency standard for new aircraft designs
Wed 18 Oct 2017 – The Federal Aviation Administration (FAA) has passed a rule that requires newly designed aircraft to harmonise with the ICAO Chapter 14 noise standard that came into effect in July 2014. In keeping with FAA numbering of aircraft noise standards, the new standard will be adopted as Stage 5 in the US. The agency believes the standard will ensure that the latest available noise reduction technology is incorporated into new aircraft designs. It represents an increase in stringency of 7 Effective Perceived Noise decibels (EPNdB) relative the previous ICAO Chapter 4 standard, or Stage 4. It will apply to new larger aircraft type designs with a maximum certificated take-off weight (MTOW) of 55 tonnes submitted for certification on or after 31 December 2017. For smaller aircraft with a MTOW of less than 55 tonnes, the standard will apply on or after 31 December 2020. The standard was passed into European Union law in January 2016.
According to the FAA, there were around 200 million passengers flying in the United States in 1975, with about 7 million people on the ground exposed to what is considered significant aircraft noise. A study it carried out in 2015 showed the number of people flying had quadrupled yet the numbers exposed to aircraft noise had dropped to around 340,000, or a 94% reduction in aircraft noise exposure.
“Reducing aircraft noise is important to the FAA because it’s an important quality of life issue for surrounding airport communities,” said FAA Michael Huerta, commenting on the adoption of the new noise standard. “We will continue to do our best through new technologies, procedures and community engagement to make aircraft operations quieter.”
The agency says it is committed to a balanced approach to the noise issue through reduction of noise at source, improved land use planning around airports and a wider use of aircraft operating procedures and restrictions that abate noise.
The background and justification for the new FAA rule, which becomes effective as of 3 November 2017, is published in the Federal Register. It notes that aircraft manufacturer Boeing and trade association Airlines for America had “supported all aspects” of the rulemaking proposal.
Current US operating rules require that jet aircraft meet at least Stage 3 (ICAO Chapter 3) noise limits. The Federal Register document says two organisations in proximity to Los Angeles International Airport, an airport community roundtable group and a municipality, had requested a phase-out of Stage 3 aircraft as part of the adoption of the new Stage 5 standard. However, the FAA says changes to the noise operating rules would have to be subject to full notice and comment rulemaking procedures, which have not been proposed. The previous elimination of Stage 2 operations had been required under two separate statutory provisions by Congress, it points out.
“The proposed Stage 5 rule does not provide any basis to attach an operational restriction, and none is included in the final rule,” it stated.
The ICAO noise certification requirements involves the measurement of noise levels at three different measurement points – approach, lateral and flyover – in order to characterise the aircraft noise performance around an airport. The EPNdB metric represents the human ear’s perception of aircraft noise. The requirements define noise limits that shall not be exceeded at each of the three measurement points and additional cumulative limit based on the sum of the three noise levels.
The ICAO noise standards are published in the Standards and Recommended Practices of Annex 16, Volume 1, with each new standard published as a new chapter, which becomes the shorthand designation of the new stringency. The new Chapter 14 follows the three other noise standards: Chapters 2, 3 and 4 – the jump to Chapter 14 is as a result of Chapter 5 already used for a different standard and the next available was 14.
The Chapter 4 standard came into force in January 2006 with an improvement on the previous standard of a little over 3dB on average at each measurement point.