ED-278A is an update of, and supersedes ED-278 of September 2020. It specifies the structure and information expected to be provided by a Concept of Operations (ConOps) for VTOL aircraft. Volume 1 of this document shall serve as guidance to structure an individual ConOps for VTOL aircraft operations. It is a first EUROCAE standard in this area and is expected to be complemented by additional Volumes that describe specific standard scenarios in more detail. This standard for a Concept of Operations applies to and can be used for VTOL aircraft regardless of the certification category (e.g. basic and enhanced according to). The ConOps identifies all relevant quantitative and qualitative aspects of the operation such as procedures, roles and infrastructure to be described and communicated to and agreed with stakeholders in general or for specific use cases.