Consultation expired with comments. The proposed Special Condition (SC) has been updated based on the comments received, and the corresponding Comment-Response Document (CRD) has been completed by EASA.
Details
Publication of Comment Response document and final Master Technical Subject post consultation.
Identification of issue
An applicant intends to install a Cabin Attendant Seat (CAS) that can be converted into a wheelchair. This wheelchair can be used either on ground during boarding and deboarding, or in flight to assist a passenger with reduced mobility. For that purpose, the CAS can be detached by the cabin crew from its installed position during the phases of flight where the cabin crew does not need to be seated. The detachable CAS, when in wheelchair configuration, can be used in the same way as a separately stowed wheelchair for the passenger cabin. The difference is the absence of need for a stowage location and the use as CAS during taxi take-off and landing and during flight when not in use as a wheelchair.
The detachable CAS will be installed on a monument, or a partition, at an already certified location for a CAS.
With the CAS being detachable during flight, without a maintenance task, there is an unusual design feature that must ensure a safe operation of the CAS when it is occupied by a crewmember.
The proposed design introduces a frequent use of the seat attaching mechanism that must comply with the emergency landing dynamic conditions and the associated loads. Therefore, the mechanism must be designed to adequately cover the frequent use. In addition, the applicant must introduce the appropriate operating procedures and maintenance procedures, including their schedule.
The applicable airworthiness regulations do not contain adequate or appropriate safety standards for such design. Special conditions are required for the certification of a detachable CAS mounted to a monument, or a partition, to supplement the CS 25 requirements.