to really keep it in memory: The 9/11 Tapes.

The 9/11 Tapes: The Story in the Air
https://www.nytimes.com/interactive/2011/09/08/nyregion/911-tapes.html

A selection of audio recordings from the Federal Aviation Administration (F.A.A.), North American Aerospace Defense Command (Norad) and American Airlines from the morning of Sept. 11, 2001. The recordings, some of which have been published previously, are being released in a multimedia report originally intended to be part of the Sept. 11 Commission’s 2004 report.