More on August's tragic small plane-tour helicopter crash over the Hudson: National Transportation Safety Board says that the small plane pilot "read back the wrong radio frequency to an air traffic controller but wasn't corrected." The pilot was never corrected and never got Newark Liberty Airport's right frequency; a minute later, his plane crashed with the helicopter. The NY Times points out, "The Teterboro controller did not catch the discrepancy in the readback. At the time, the controller, alone in the tower, was in the midst of a personal phone call, and in addition, there was other voice traffic on the radio frequency at that point." The plane's three occupants were all killed, as were the chopper's six.