FAQ n.19390

When my aircraft does not meet, or has shown not to have met, applicable airworthiness requirements and as a result does not hold a valid Certificate of Airworthiness or Restricted Certificate of Airworthiness, but is capable of a safe flight under defined conditions and for the purposes listed on point 4.2 of Form 37 (Application for Approval of Flight Conditions for a Permit to Fly).

Note that the Member State of Registry can also grant an exemption to allow an aircraft to fly without a valid Certificate of Airworthiness or Restricted Certificate of Airworthiness under the provisions of Article 71 of the Basic Regulation (Regulation (EU) 2018/1139), if it finds that the conditions of this article are met.