A giant lung bulla occupies at least a third of the lung space. We present a middle-aged man who lost consciousness during an air flight for 30 minutes, without any respiratory symptoms. An incidental finding on chest x-ray revealed a giant bulla and a chest computed tomography imaging confirmed the diagnosis and ruled out a tension pneumothorax. A giant lung bulla is an uncommon cause of loss of consciousness and may be suspected if it occurs during air travel.