GM 21.B.107 and 21.B.111 Operational suitability data (OSD) considerations for the approval of changes to type certificates (TCs) or supplemental type certificates (STCs)    

CAA ORS9 Decision No. 1

The requirement for the CAA in points 21.B.107(c) or 21.B.111(c) are applicable to necessary changes to the OSD as foreseen by 21.A.95(b) Section 2 for minor changes, 21.A.97(b) Section 2 for major changes, and 21.A.115(b) Section 3 for STCs. By analogy, these requirements should also be considered by design organisation approval (DOA) holders that approve changes or issue supplemental type certificates (STCs) under their privileges (without the CAA’s involvement), as stated in the GM to A.21.A.90A.

Changes to TCs can comprise several interrelated changes to the TC. For example, a change to the cockpit design may trigger a necessary change to the flight crew data, which is part of the OSD, and is, therefore, included in the TC.

Interrelated changes (e.g. type design changes and necessary changes to the MMEL and/or flight crew data) should be approved together under a single approval.