Amazon delivery drones crashed during test flight after removal of rain-proof safety sensor: report
1. Amazon's delivery drones crashed during a December test flight due to software issues. 2. NTSB investigation found faulty lidar readings heightened risks during rain. 3. The removal of safety sensors may have contributed to the crashes. 4. Amazon claims its MK30 drone is safer despite the incidents. 5. The drone delivery program faces ongoing delays and regulatory challenges.