SOPs in AS9100 Rev D

Answer:
There is not a requirement in AS9100 Rev D to have any particular required Standard Operating Procedure (SOP), but there is certainly an allowance for these as “documented information to support the operation of its processes” (Clause 4.4.2). The decision is up to the company to determine if any process needs documented information to be maintained for the process to work properly, and this applies to production processes as well as any others in the QMS.
For more information you can see a list of the mandatory documented information for AS9100 Rev D here: https://advisera.com/9100academy/knowledgebase/list-of-mandatory-documents-in-as9100-rev-d/