You are more likely to choke to death on a pretzel than to die in a plane crash. With just one fatal accident for every 16m passengers flown, 2017 was the safest year ever for air travel. But one area of concern relates to the danger that drones pose to aeroplanes. A recent report found that drones buzz too close to planes about 250 times every month. Although light, they are capable of harming an airliner’s engine, wing or windscreen