Onboard aircraft medical emergencies are on the rise as commercial air traffic is increasing. However, thoracic injury secondary to air travel is extremely rare and, most reported injuries are cases of pneumothoraces. Spontaneous pneumomediastinum and pneumopericardium have been barely reported in the medical literature as a complication of air travel. We are reporting a case of spontaneous pneumopericardium and pneumomediastinum in a patient with Gardner's Syndrome after a flight from Central America to New York City. The patient presented with chest discomfort. He was managed conservatively with oxygen therapy as he was hemodynamically stable throughout his stay in the hospital. A thorough work up in hospital including and esophagogram and a CT scan of the chest were none revealing of the cause. However, the patient was noted to have metastatic rectal cancer with lung involvement. The patient was discharged with instructions to avoid air travel.