Elderly people aged 85, as long as they do not have chronic underlying diseases, can fly in principle, but there are certain hidden dangers: 1. Asthma, pulmonary embolism and other respiratory diseases, resulting in breathing difficulties, cyanosis and other signs of oxygen deprivation in the elderly. For elderly people aged 85, a comprehensive physical examination must be conducted before taking a flight to ensure that they are in good health before taking a flight. For the elderly with chronic diseases must take the plane, should be prepared to rescue drugs, such as quick-acting heart pills, nitroglycerin, bronchodilators and so on.