Abstract: Aiming at the non-normative problems of item Q and item E in the notice to airmen（NOTAM）, a method of text similarity calculation in natural language processing is proposed to identify the non-normative NOTAMs. Firstly, translating the item E into Chinese by statistical machine translation method, and translating the item Q into Chinese by establishing a database. Then, Word2vec model is used to calculate the similarity between the two sentences, and the recognition standard of non -normative NOTAMs is established. Based on the similarity calculation of item Q and item E in 500 collected NOTAMs, 0.7 is set as the benchmark of non -normative NOTAMs. The data test shows that the recognition accuracy of NOTAMs is 96.2%, which verifies the feasibility of non-normative NOTAMs recognition method based on NLP.

Key words: natural language processing, notice to airmen, machine translation, Word2vec, text similarity calculation