Transcript for Probe into Grand Canyon helicopter crash focuses on critical piece of equipment
In the meantime, we have new reporting tonight after that deadly helicopter crash in the grand canyon. The sightseeing helicopter plunging into a deep ravine, erupting into a fire ball. Three people were killed. Four seriously injured. And in the video, you can actually see one of the passengers crawling out to safety. Tonight here, new questions about these helicopters used for tours. And here's ABC's Marci Gonzalez near the scene of the crash tonight. Reporter: Investigators tonight trying to piece together if the helicopter had a critical piece of equipment designed to prevent explosions like this one. The crash resistant fuel system is a very important part of this investigation. Reporter: This woman, seen right there, emerging from the wreckage, one of four survivors of this helicopter crash that killed Stuart hill, his girlfriend and brother. The group visiting from the United Kingdom to celebrate Stuart's birthday, touring the grand canyon around sunset Saturday when investigators say a storm moved in. Rescuers rushing to the scene facing rugged terrain and wind gusts up to 50 miles an hour, stranding them and the victims in the canyon for more than eight hours. What we were doing was mainly just stabilizing the patients. Reporter: This, just one of 15 fatal sightseeing helicopter crashes since 2003. The survivors, including these newlyweds and the helicopter's pilot, finally airlifted out, listed in critical condition tonight. David, the NTSB team on-site here is looking for cell phones and videos in the wreckage, reviewing weather data and looking to talk to witnesses as they try to figure out if this crash could have been prevented.
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