The objective of this Notice of Proposed Amendment (NPA) is to mitigate the safety risks linked to the operation of helicopters for extended time periods over water.
Previous studies and accident investigations into helicopter ditching and water impact events had highlighted the need to enhance the certification specifications for helicopters (CS-27, CS-29) in order to improve the level of safety of future helicopter designs. As part of RMT.0120, changes were introduced to CS-27 and CS-29 at Amendment 5 to improve the probability of survival for occupants in the event of either a helicopter ditching or a survivable water impact.
An assessment has been conducted by the European Union Aviation Safety Agency (EASA) of the appropriateness of requiring design improvements to existing helicopter designs and the in-service helicopter fleet based on the above-mentioned specifications introduced in CS-27 and CS-29.
Based on that assessment, this NPA proposes to amend Part-26 and CS-26 to require the following design improvements:
- Easier identification of the operating mechanisms for emergency ditching underwater exits;
- Provision of remote life raft deployment;
- Substantiated sea conditions for capsize resistance in the rotorcraft flight manual (RFM);
- Verified easy opening force for emergency ditching underwater exits;
- Life raft attachment means of a sufficient length to prevent damage to the life raft;
- Easy access to life preservers;
- Automatic illumination of emergency ditching underwater exits;
- Improved ratio of passengers to emergency ditching exits;
- Verified robustness of existing emergency flotation systems to resist damage in the event of a water impact;
- Automatic deployment and arming (if required) of the emergency flotation system.
In addition, this NPA also proposes some minor improvements to the certification specifications for new applications for certification for ditching and emergency flotation to improve the clarity of the previous amendments.
The proposed amendments are expected to increase safety with a minimal economic impact on helicopter operators and helicopter manufacturers.