Article 4 Obligation to investigateF1 United Kingdom Repealed Original text. Later amendments are not shown. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Annotations Textual amendments F1 Repealed by Regulation (EU) No 996/2010 of the European Parliament and of the Council of 20 October 2010 on the investigation and prevention of accidents and incidents in civil aviation and repealing Directive 94/56/EC Text with EEA relevance. ← Article 3 Article 4 Article 5 →