In 2001 , the International Civil Aviation Organization ( ICAO ) specify that English would , from then on , be the standardized language of air travel change of location , and issued a directive that say that all airmanship personnel — pilots , flight gang , and air traffic controllers — must pass an English proficiency mental testing . Themandatory abidance datewas March 5 , 2008 . Not only must applier know the appropriate aviation terminology in English , they must also be capable to read English instructions via radio , with no facial cues to prompt them . They also must learn to develop as benign an accent as potential , so that they are “ intelligible to the aeronautical community of interests . ”
English has been the unofficial terminology of pilots for many years , but a tragical fortuity in the Canary Islands in 1977 emphasized the penury for a universal aviation language . In this case , two 747 jet — one Pan Am , one KLM — collide on the track at Tenerife airdrome . At one point , the KLM pilot told the tower in a heavy Dutch accent either “ We ’re now at take - off ” or “ We ’re uh … taking off . ” The tower did n’t understand the message and assure KLM to standby , but a simultaneous communication from Pan Am garbled the instruction . Reviews by the NTSB of the cockpit fipple pipe transcription determined that the KLM pilot ’s use of non - standard phraseology during the vital import leading up to the fortuity contributed to the calamity .
Most of the 185 member state of the ICAO had no problem with the English language provision , economise for three major airports : Charles de Gaulle in France , and Ottawa International and Montreal - Dorval International , both in Canada . It was partly because these three hub wanted to communicate exclusively in French that the ICAO make up one’s mind to actually put a legal philosophy in writing .
