“Is there a doctor on board?”
Probably, yes. If your fear stems from the chance you could suffer a cataclysmic medical incident without a medical professional nearby, rest assured this is fairly rare (according to one study published in the New England Journal of Medicine, an emergency is reported on one flight for every 609). Physician passengers provided medical assistance in 48.1 per cent of in-flight medical emergencies, and aircraft diversion occurred in 7.3 per cent of them. The study was able to follow up with 10,914 of these patients and found that 25.8 per cent were transported to a hospital, 8.6 per cent were admitted, and just 0.3 per cent died. These are the things you should never do on an airplane.