The knowledge of air traffic control is something that is invaluable because it gives the safety investigator an edge. An air traffic controller can handle up to 1000 passengers at a go. It is after that, you will be sent to a facility for on the job training to put what you have learnt into practice. You will also be able to tell if the air traffic controller gave the right direction to the pilot. You get information from the air traffic controllers, from the aircraft log book, and we also ask the crew questions.

Source: The Guardian July 24, 2020 02:48 UTC