We present the case of a 59-year-old man with congenital kyphoscoliosis who developed cor pulmonale for the first time following intercontinental air travel. Prolonged exposure to the low partial pressure of oxygen in the cabin of the aircraft led to pulmonary hypertension and right heart failure. The case highlights the potential for long-haul air travel to cause decompensation in patients with thoracic deformity and apparently stable cardiorespiratory function. It also emphasises the need for patients and their medical attendants to carefully consider the potential health implications of the hypoxic atmosphere in pressurised aircraft.