9:50 a.m. September 11, 2001: United Airlines Manager Tries Unsuccessfully to Initiate Lockout of Flight 93

Rich Miles, the manager of United Airlines’ System Operations Control center outside Chicago, tries to initiate the “lockout” procedure for Flight 93, which would acknowledge an emergency on the flight and safeguard information about it, but he is unable to do so. At some time between 9:45 a.m. and 9:50 a.m., the United Airlines maintenance facility in San Francisco contacted Miles about a call it had just received from an attendant on Flight 93, reporting that her plane had been hijacked (see 9:35 a.m. September 11, 2001). In response, Miles attempts to initiate a lockout of Flight 93. Lockout is a standard procedure for airlines in safety and security incidents, which isolates information about a flight so the case can be managed by the airline’s top leadership, and protects the identities of the passengers and crew. But Miles is unable activate this procedure. According to the 9/11 Commission, this is because United Airlines has already conducted a lockout of Flight 175 (see (9:21 a.m.) September 11, 2001), and its computer system is not presently set up to deal simultaneously with two such procedures. [Wall Street Journal, 10/15/2001; 9/11 Commission, 8/26/2004, pp. 12-13 and 43]