The collision occurred in airspace that is difficult to navigate. Flight data, video and air traffic control audio show how the tragedy unfolded.

In a blog post published this week, DJI said it was doing away with geofenced No Fly Zones and replacing them with “enhanced warning zones,” maintained by the Federal Aviation Administration.

A giant Chinese drone maker has released a new update, effective immediately, which allows its products in the US to fly over spaces which were until now designated as “no fly zones.” ...