The purpose of this study is to determine whether English-French and French-English translations of press releases on aviation accident investigations contain differences in textual elements which influence readers' comprehension, and whether translators tend to create target texts which are more or less comprehensible than their source texts. It also seeks to identify whether such differences are attributable to the translation process itself (bidirectional) or a specific language direction. The paper begins with a theoretical framework on technical communication and translation, popularization, and explicitation. It then discusses the method and findings. Twenty English-French translations and twenty French-English translations were analyzed. All translation choices involving changes in elements affecting comprehensibility were recorded for each language direction. Elements which influence comprehensibility include those which are typical in technical and popular texts, and explicitation and implicitation operations. In conclusion, both language directions showed a tendency of translators to make changes which enhanced readers' comprehension.