The objectives of this Decision are to:
(a) reduce the number of large-aeroplane accidents and serious incidents where aeroplane performance is a causal factor, while harmonising the use of reported runway surface conditions in aeroplane performance assessments;
(b) reflect the state of the art in large-aeroplane certification by selecting non-complex, non-controversial, and mature items;
(c) address three safety recommendations (SRs) in the areas of turbopropeller vibrations and windshield systems; and
(d) better harmonise the Certification Specifications and Acceptable Means of Compliance for Large Aeroplanes (CS-25) with the corresponding related International Civil Aviation Organization (ICAO) Standards and Recommended Practices (SARPs) and Federal Aviation Administration (FAA) Advisory Circulars (ACs).
This Decision amends CS-25 to:
(a) upgrade the certification standards for computing take-off and landing performance (including at the time of arrival);
(b) require that turbopropellers on large aeroplanes are equipped with a vibration indication system;
(c) introduce acceptable means of compliance (AMC) on the investigation of propeller vibrations during descent to ensure that certain conditions are addressed;
(d) ensure that applicants fully define and control the material strength and other properties that are used in part fabrication methods, considering the unique, product-specific combinations of materials and/or processes, and/or methods of manufacture and assembly;
(e) ensure that applicants properly address windshield system failure conditions that may have structural effects; and
(f) update a reference table in AMC 25 Subpart H; introduce references to FAA AC 25-17A ‘Transport Airplane Cabin Interiors Crashworthiness Handbook’, and correct editorial errors.
The amendments are expected to:
- increase the current level of safety by addressing three SRs;
- improve harmonisation with the related FAA standards and ICAO SARPs on aeroplane performance assessment; and
- have some positive economic impacts and no social or environmental impacts.
