# The Air Navigation (Noise Certification) Order 1987, Article 3: Interpretation


(1) In this Order—
“An International Standard Atmosphere at sea level” has the meaning specified in Schedule 2 to this Order;
“Authorised person” means any constable and any person authorised by the CAA (whether by name or by class or description) either generally or in relation to a particular case or class of cases;
“BCAR” means the British Civil Airworthiness Requirements Section N — Noise Issue 4 dated 1st January 1988;
“By-pass ratio” means the ratio of the air mass flow through the by-pass ducts of a gas turbine engine to the air mass flow through the combustion chambers calculated at maximum thrust when the engine is stationary in an International Standard Atmosphere at sea level;
“dB(A)” means the unit for expressing A-weighted overall sound pressure level as specified in BCAR;
“EPNdB” means the unit for expressing effective perceived noise level as specified in BCAR;
“LAX” means the A-weighted noise energy of a single aircraft noise event as specified in BCAR;
“The CAA” means the Civil Aviation Authority;
“The Convention” means the Convention on International Civil Aviation signed on behalf of the United Kingdom at Chicago on 7th December 1944;
“Derived version” means a modification of a prototype aircraft which, from the point of view of airworthiness, is similar to the prototype but incorporates changes in type design which may affect its noise characteristics adversely;
“Noise certificate” means a certificate issued or validated or other document approved by the competent authority of a State to the effect that the aircraft to which the certificate or other document relates complies with the applicable noise certification requirements in force in that State;
“prescribed” means prescribed by Regulations made by the Secretary of State under this Order.
(2) Expressions used in this Order shall unless the context otherwise requires, have the same respective meanings as in the Air Navigation Order 1985.
(3) A power to make Regulations under this Order shall include the power to make different provisions with respect to different classes of aircraft and with respect to different circumstances and to make such incidental and supplementary provisions as are necessary or expedient for carrying out the purposes of this Order.

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Source: https://www.legislation.gov.uk/uksi/1987/2212/article/3 (the official version)
Page: https://openlegislation.uk/air-navigation-noise-certification-order-1987/article-3
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.