A train event recorder – also called On-Train Monitoring Recorder (OTMR), On-Train Data Recorder (OTDR), Event Recorder System (ERS), Event Recorder Unit (ERU), or Juridical Recording Unit (JRU) – is a device that records data about the operation of train controls, the performance of the train in response to those controls, and the operation of associated control systems. It is similar in purpose to the flight data recorder or black box used on aircraft.
Juridical Recording (orange) Blackbox as part of an ETCS equipment
Indusi I60 ER24 control device with the DSK recorder inside
A flight recorder is an electronic recording device placed in an aircraft for the purpose of facilitating the investigation of aviation accidents and incidents. The device may often be referred to colloquially as a "black box", an outdated name which has become a misnomer—they are now required to be painted bright orange, to aid in their recovery after accidents.
A modern flight data recorder; the underwater locator beacon is the small cylinder on the far right. (Translation of warning message in French: "Flight recorder do not open".) The warning appears in English on the other side.
Cold War-era Soviet MS-61 cockpit voice recorder from a MiG-21 interceptor
A Fairchild A100 cockpit voice recorder, on display in the Deutsches Museum. This is a magnetic-tape unit built to an old standard, TSO C84, as shown on the nameplate. The text on the side in French says "Flight recorder do not open".
"Mata-Hari" flight data recorder