So English is not only the required international language for pilots worldwide. It is also apparently the language of science! 75% to 90% of all scientific papers today are published in English. 61 of the world's top 100 universities are located in an English-speaking country. That's a lot of foreign language learning for smart people!
To quote a blog that I've read:
"English is without a doubt the actual universal language. It is the world's second largest native language, the official language in 70 countries, and English-speaking countries are responsible for about 40% of world's total GNP"
Using English is the most practical language to use for most literary papers as it can reach the most number of people and countries based on the data above.