AMC E 540 Strike and ingestion of foreign matter

(1)When complying with CS-E 540(a), the substantiation of the strike and ingestion effects of foreign objects such as cleaning cloths, hand tools, rivets, bolts and screws needs only to be carried out if these are likely to be more severe than those of the single large bird strike / ingestion. As well as being part of the demonstration of compliance with CS-E 540(a), the effects of the large bird ingestion test of CS-E 800 on the spinner or any Engine static part, as a result of a bird strike, should be assessed against the criteria of CS-E 510. Main frame struts or bifurcation strut fairings may be exposed to impact from birds or bird debris. Such frame struts or strut fairings may house fuel, oil, hydraulic, high-pressure bleed air lines, or wiring associated with the engine control system. The applicant should consider the potential for bird induced damage to these ducts, lines or wires with regard to the objective of CS-E 540. In order to verify the Extremely Remote criteria for Hazardous Engine Effects in case of bird strikes as required in CS-E 540(a), consideration should be given to the possibility of aircraft operation at speeds higher than 200 knots, associated with the corresponding probability of occurrence of encountering a single bird under such conditions.

(2)CS-E 540(b) is intended to address for example rain, hail, ice, gravel, sand, small and medium birds. For some threats the interpretation of the specifications of CS-E 540(b) should be made in relation to other CS-E specifications, such as CS-E 800 for birds or CS-E 790 for rain and hail, which may quantify the safety objectives of CS-E 540(b). These related paragraphs are therefore intended to be sufficient for demonstrating compliance with CS-E 540(b) for the considered subject. Nevertheless, any unusual finding made during these demonstrations of compliance should be assessed against the safety objective of CS-E 540(b) continued safe flight and landing.

[Amdt No: E/1]