reliable enough for life safety uses. It is also true that most trunked radio system users are likely to hear busy signals, (error tones showing no channels are available,) for the first time during a large disaster. All systems have a finite capacity. "We don't want or need trunking" is what Chief Charles Dowd (NYPD) was heard to say at an APCO convention in Orlando (2006). NYPD operates a large, conventional repeater network with many legacy channels in the UHF band; and a technology developed "so a large number of users can share a small number of channels" (e.g. trunking) is clearly unnecessary and a frivolous waste of money. With sufficient channels, there is no need for trunking. There are no 'busy' tones in a conventional repeater system. In the event an individual needs to chime in, he simply waits his turn – just as he would do in a trunked system. Mobile data terminals All 911 ambulances and other FDNY vehicles have data terminals, sometimes referred to by staff in recordings and transcripts as MDTs. These terminals are connected to the computer-aided dispatch (CAD) back end or server. They can display text, page through screens describing jobs, and display lists of units assigned to a job. A thorough analysis of data communications is not possible. What recordings show is that data terminals in at least some field units did not work properly during at least a portion of the incident. At 09:11:14, Division 3 told Manhattan Fire dispatch, referring to the summary screen, "Summary is only giving me a few units. You're going to have to give it to me over the radio. I'm ready to write." This means the terminal was not displaying the entire list of units assigned to Division 3, as it would under normal conditions. The work-around: the Chief had to hand-write the list of units responding. In this one instance, the dispatcher reading the list of about 29 units tied up the Manhattan Fire channel for 53 seconds. During the reading of the list of units responding, one can hear several FDNY units try to interrupt the dispatcher. Their radio traffic was delayed until the entire list was read. This need to read lists of units because of slow or inoperable terminals occurred in at least three or four cases. It's unclear what caused data delays and incomplete screens on the mobile data terminals.