Can I, as a DOA holder, approve flight conditions and issue permits to fly for ferry flights?
Yes, as long as you have the privilege to approve flight conditions and issue permits to fly in the terms of approval of your DOA, and you comply with the conditions and limitations that are mentioned there. In all cases the privilege to approve flight conditions by a DOA holder is limited to cases where the approval is related to the safety of the design. And the DOA Holder can only obtain the privilege to issue a permit to fly for in-service aircraft when it has demonstrated that it is able to control the configuration of the aircraft.
It is important to take into account that the mentioned privileges are always related to the technical scope of the DOA. For example, a DOA which has those privileges in the terms of approval may issue a permit to fly to perform a ferry flight with an aircraft which has an expired and not still implemented airworthiness directive. Nevertheless, in order to do that the DOA should have the proper design capability, as reflected in the terms of approval, to evaluate the design aspects that are related to the impacted airworthiness directive and to be able to substantiate that the aircraft is capable of safe flight. For example, DOAs not having the avionics technical field in the terms of approval cannot approve a permit to fly to perform a ferry flight when the overdue airworthiness directive is related to avionics, even having the privileges to approve flight conditions and issue permits to fly.