AMC-ELA No 1 to 21.A.239(a) Design assurance system – Definition

CAA ORS9 Decision No. 1

The term ‘design assurance system (DAS)’, in the context of the AMC-ELA to Subpart J, refers to those elements of product development and certification that ensure the control and supervision of the initial design, of changes or repairs to the design, and its continued airworthiness with respect to the applicable type certification basis, the operational suitability data certification basis and the environmental protection requirements. Therefore, elements to be considered as part of the DAS are:

1. the generation, iteration, CAA acceptance and maintenance of the certification programme;

2. the demonstration of compliance and its verification within the design organisation;

3. the declaration of compliance provided by the design organisation to the CAA;

4. monitoring functions to ensure the continued airworthiness of the certified product, including the resulting activities;

5. independent system monitoring of the compliance with, and the adequacy of, the documented procedures of this system.

A typical development process will include a number of additional activities, such as preliminary design, project management elements (a PDR, CDR, etc.), or development activities (test platforms, demonstrators, feasibility studies), etc., that are not part of the DAS, even when elements of the DAS form specific milestones in the development path. In the context of this Subpart, those other activities are consequently excluded from the assessment of the DAS, even when elements of the DAS are also applied to those activities.