The utilisation of Aviation English is paramount in ensuring the safety and efficiency of the aviation industry, and it serves as a preventative measure against incidents and accidents related to communication. This study examines the challenges in radiotelephony communication faced by Korean pilots and air traffic controllers, who are English as a second language (L2) speakers. The study aims to identify the causes of communication difficulties and to explore effective English educational materials to mitigate these diffi-culties. The research employed a questionnaire to gather the perspectives of pilots and controllers, who are experts in the aviation industry, regarding the issues. The results indicate that communication difficulties are caused by a lack of English language profi-ciency, excessive use of plain language, rapid rate of speech, and accents that deviate from standard English. Moreover, the results suggest that practical training, using materials such as real transmission voice recordings and diverse vocabulary resources, can enhance speaking and listening comprehension skills in non-routine situations. This study provides valuable insights for the development of effective training programs and materials, which could help reduce communication difficulties and improve the safety and efficiency of aviation operations. & COPY; 2023 Elsevier Ltd. All rights reserved.