The accident that provoked the installation of the secure area at Summit happened on February 1, 1996 when Santa Fe train H-HBALT1-31 derailed at milepost 60.4 near Cajon.

The conductor and the brakeman, who jumped, received fatal injuries and the engineer, who remained aboard, incurred serious injuries. A fire resulting from the derailment and subsequent locomotive and freight car pileup engulfed the train and adjacent areas.

The NTSB report number is RAR-96/05 if you want to look it up.

As "still waiting" mentioned above, not only did this accident result in the secure are at Summit, which some refer to as "Fort Summit" now, but also the adoption of two-way EOT devices. As far as the dynamic brake holding feature, I don't recall that being a product of this wreck, or a mandate from the FRA as a result of this wreck. The UP already had this on their locomotives at the time. It worked great unless you had a foreign road unit in the lead, in which case you would lose all dynamics upon making an emergency application. This was a unexpected surprise to many UP engineers, who didn't know ALL the dynamics would be lost just because of the leader. Every now and again, this certainly raised the bar on the "pucker factor" while trying to get down the hill.