40 years ago, the worst air disaster ever took place on the runway of the airport of the Canary Island of Tenerife. Two Boeings collided there at full speed. One Boeing did not yet have permission to enter the runway, but other circumstances also played a role. For example, it was very foggy and there was confused communication with the control tower. Since then, flying has become much safer. In the 1970s, there were about 2000 people killed by plane crashes, among 2011 and 2015 that average was about 370. According to the VNV (United Dutch Airline Pilots) is this mainly due to a culture change within the aviation sector. pilots, technicians and ground crews are allowed to make mistakes and come to terms with them, so everyone can learn from it. (Source: US)