Description: A Dutch-led team of investigators have revealed Malaysia Airlines Flight 17 was brought down by a Buk surface-to-air missile which exploded less than a metre from the cockpit. All 298 people on board the Boeing 777 died in the crash, which happened as the plane flew at 33,000 feet over eastern Ukraine in July 2014. Sky's David Bowden's special report looks at the findings of the Dutch Safety Board and explores the questions which remain unanswered.