A missing plane - which remains a mystery. A British Airways flight - crash landing at Heathrow. We've seen the reports on the news but, still, aircraft safety has come a long way since the early days of passenger travel.
When planes do crash, the men and women of the Air Accident Investigation Branch are some of the first people to arrive. Many damaged craft are taken to the AAIB's base - at Farnborough - for further examination.
In the first of two special reports, Divya Kohli has been given exclusive access - to see the work going on behind the scenes