<p>This security camera footage shows the moment the blades of two Pasadena Police Department helicopters collided at a heliport in Altadena, California, on November 17, 2012, leaving both damaged and injuring six people, according to reports.</p><p>The video was released</a> by the National Transportation Safety Board (NTSB) in August, 2016, but only came to light in early March, 2018, when it was published by US news media</a>.</p><p>The footage shows one helicopter attempting to land at the heliport next to another that was preparing for a flight. NTSB</a> said blamed the collision on rainy weather and a lack of communication between pilots – the landing pilot’s failed to seek clearance from the departing pilot, who should have parked the chopper inside a marked pad but did not do so due to drainage issues.</p><p>“At the time of the accident, there was no established monitored UNICOM frequency at the heliport, and there were no procedures to alert ground personnel that a helicopter was arriving to the heliport other than by ground personnel ‘hearing’ it approach,” NTSB</a> said. Authorities have since had monitored universal communications radio procedures in place for helicopter arrival and departure. Credit: National Transportation Safety Board via Storyful</p><br />
