Interestingly, when I worked for TNT Airways in Liege, the Working Language was English for absolutely everyone regardless of whether they worked in an office, in the warehouse, on the ramp or flew the aeroplanes. Over the years we had pilots from all over the world including Nigeria and Uruguay. We all got on just fine. Of course, most of our Belgian pilots already spoke at least three languages. As usual, us Brits were completely bloody lazy when it came to learning another language.