Cause of failed Alaska Airlines landing gear that sent passengers screaming revealed

Nearly two years after passengers screamed while sparks flew down a runway during the landing of an Alaska Airlines flight the cause has been revealed A final description by the National Transportation Safety Board NTSB published on Tuesday points to incorrect maintenance work The flight which departed from Seattle Washington made a hard touchdown in Santa Ana Calif during Tropical Storm Hilary after the left main landing gear collapsed on touchdown Video recorded by a tourist captured the plane slamming into the ground at high speed Sparks were seen flying as the plane appeared to drag its left wing along the tarmac ALASKA AIRLINES PASSENGERS SCREAM AS PLANE MAKES HARD LANDING AMID TROPICAL STORM HILARY 'SPARKS OUTSIDE'Investigators revealed that the case was caused by a fatigue crack of a metal trunnion pin which is part of the left landing gear The fracture formed from excessive grinding during a maintenance overhaul which introduced heat damage to the metal While the crack was initially not visible it grew over time and ultimately caused the pin to fracture during landing the NTSB record commented Results of this examination and previous NTSB investigations demonstrate that even relatively mild heat exposure from grinding and or machining during overhaul can lead to cracking which can lead to fatigue crack development and failed landing gear components as occurred in this accident the analysis stated DELTA PLANE'S LANDING GEAR COLLAPSED DURING TORONTO CRASH-LANDING INVESTIGATORS SAYThe review added that the pin had endured more than landing cycles since undergoing the maintenance work The crack itself had likely been present for approximately landing cycles the NTSB discovered Although the aircraft sustained substantial damage from the hard landing all passengers and crew members were able to deplane safely and without injury Alaska Airlines previously noted our focus is taking care of our guests who were on board including retrieving their checked bags We apologize for the inconvenience and appreciate their patience during this situation Alaska Airlines did not instantly respond to a request for comment from Fox News Digital Fox News' Chris Pandolfo contributed to this analysis