22. Commission Implementing Regulation (EU) 2021/664 of 22 April 2021 on a regulatory framework for the U-space - European Air Law (Update) View the chapter 22. Commission Implementing Regulation (EU) 2021/664 of 22 April 2021 on a regulatory framework for the U-space by - European Air Law (Update) 22. Commission Implementing Regulation (EU) 2021/664 of 22 April 2021 on a regulatory framework for the U-space