Large aeroplane manufacturers are faced with limitations in terms of available means to demonstrate compliance with current CS-25 certification specifications related to the safe operation of large aeroplanes in supercooled large drop (SLD) icing conditions (as defined in Appendix O ‘Supercooled Large Drop Icing Conditions’ to CS-25).
These limitations present substantial challenges not only for the certification of new or modified conventional large aeroplane designs, but also for the development of innovative large aeroplane designs and sustainable technologies that aim to reduce aviation’s environmental impact
The objective of this rulemaking task is therefore to develop amendments to CS‑25 that will:
- provide practical means to demonstrate safe operation following encounters with Appendix O SLD icing conditions;
- clarify the steps required to establish an acceptable threshold for safe operation; and update the associated acceptable means of compliance to enhance the overall effectiveness of the certification process.