“At 9:44 [on September 11, 2001], NORAD reported to the Air Threat Conference Call [held by the Pentagon] that Delta 1989 might be a hijacked plane based on the information NEADS [NORAD’s Northeast Air Defense Sector] had received from the FAA’s [Federal Aviation Administration’s] Boston Center. Four minutes later, a caller from the White House shelter asked if there were any further reports of hijacked planes; the National Military Command Center’s deputy director mentioned Delta 1989, reporting that ‘that would be the fourth possible hijack.’ There was no mention of United 93.”
– John Farmer, The Ground Truth, Pages 209-210