BLITZER: We're learning new details about the deadly helicopter crash on top of a New York City skyscraper. An FAA spokeswoman says the pilot did not have the required instrument rating to fly in bad weather. An NTSB official says a flight data recorder and voice recorder were not installed on the helicopter but were not required. Nor was the pilot required to be in communication with the air traffic control. But the official notes that the pilot may have tried to make radio calls. Investigators have been carrying out witness interviews including one with the passenger dropped at the Manhattan heliport just prior to the incident. Investigators want to remove the wreckage from the roof as soon as possible. The NTSB official says the preliminary report should be expected in about two weeks but will not deal with the cause of the crash. A full investigation could take up to two years. We'll stay on top of this story. To our viewers, thanks very much for watching. You can follow me on Twitter and Instagram @WolfBlitzer. Tweet the show @CNNsitroom. "ERIN BURNETT OUTFRONT" starts right now.
Clues Emerge About Deadly Helicopter Crash on New York Skyscraper.