Environmental irritants acts as modulators of airway inflammation in these contiguous airways. Eastern Air Lines, Braniff Airways and Northwest Airlines followed. An Airbus A319 is to be repainted into British European Airways livery. Sputum is mucus that is coughed up from the lower airways (the trachea and bronchi). The respiratory tract is divided into the upper airways and lower airways. These effects cause lesions of the mucous membranes of the upper airways. Most cases arise in the larger airways (primary and secondary bronchi). Mucus helps to moisten and protect the airways. This interested Lufthansa, Qatar Airways and ILFC. It serves as the primary hub for Kuwait Airways and Jazeera Airways. Both were Avro Tudor IV passenger aircraft operated by British South American Airways. British European Airways (BEA) coordinated all British civil aircraft operations. Other carriers including All Nippon Airways and Delta Air Lines also ordered winglet kits. Since 2011, it handles several flights daily operated by Fly Montserrat Airways. Branson formed Virgin Atlantic Airways and Virgin Cargo in 1984.