Train event recorder

Train Event Recorders are similar to, but in Europe at least, pre-date the black boxes found on aircraft. They record data about the operation of train controls and performance in response to those controls and other train control systems.
Data storage is provided by magnetic tape (now obsolete), battery-backed RAM and most recently nonvolatile EEPROM or "Flash Memory" overwritten in a FIFO continuous loop.
The data is mainly used in the investigation of accidents and incidents but can also be used to monitor traction unit performance and the competence of drivers.

History

The earliest event recorders were the mechanical TEL® (abbreviation of "Telegraphenwerkstätte von G.Hasler") speed recorders of 1891, which recorded both time and speed.

Regulations

United States

The Federal Railroad Administrations (FRA) "Final Rule 49 CFR Part 229", (revised June 30, 2005) requires that Event recorders be fitted to the leading locomotives of all US, Canadian & Mexican trains operating above 30 MPH on the US rail network including all freight, passenger and commuter rail locomotives but does not apply to transit running on its own dedicated tracks.

The new ruling applies to locomotives either ordered before Oct 1, 2006 or placed in service after Oct 1, 2009 and included:

• Improved crash worthiness by means of a “hardened” memory module able to withstand:
  • Fire resistance of 750 C for 1-hour- this test simulates the temperature of burning diesel fuel
  • Impact shock of 55g
  • Static crush of 110kN for 5-minutes - this test simulates a locomotive derailment and blunt object impact
  • Fluid immersion in Diesel, water, salt water or lube oils for 2-days
  • Hydrostatic pressure equivalent to immersion to a depth of 15 m in water for 2-days
• Recording of additional information to enhance the quality of information available for post-accident investigations including the following “safety-critical” signals:
  • Speed
  • Direction of travel (Forward or Reverse)
  • Time
  • Distance
  • Throttle position
  • Operation of brakes
  • Status of Headlights & Marker Lights (On or Off)
  • Operation of Horn
  • Status of Cab signals
• Store the last 48 hours of safety-critical train data. This is to prevent over-writing of the crash data if the loco is used for the subsequent "clean-up" of the crash scene.
• The phasing out of the old magnetic tape models over a four year period due to their vulnerability to data loss in the event of a crash.

United Kingdom and Ireland

All trains operating on Network Rail controlled infrastructure are required to be fitted with an Event recorder complying with GM/RT 2472. Ireland has also adopted this regulation.

Crash protection requirements:

• Fire resistance of 700 C for 5-minutes
• Impact shock of 100 g, 3 times on each of its 6 sides
• Static crush of 20kN for 1-minute, to all edges and faces
• Fluid immersion in water, AFFF or R134A for 1-hour
• Magnetic field produced by a current of 0 to 64kA, rising at 10⁷ A/sec at a distance of 1-meter

The UK approach is similar to US requirements, but the list of required signals is more comprehensive. This reflects, in part, the prevalence of passenger trains and the inevitable possibility of incidents involving access doors.

Signals to be recorded include:

• Brake demand including operation of all Brake Controls & other brake activations
• Power notch
• Wheel speed
• Speedometer, both signal sent to speedometer and indication displayed to driver
• AWS operation
• DRA operation
• Vigilance Operation
• PES - Passenger Emergency Systems,
• Override of any Safety System
• Horn
• Door signals
• Door inter-lock
• WSP
• Tilt, if fitted
• Speed supervision & Control, if fitted

Switzerland

Speed recording equipment has been used by Swiss Federal Railways for many years.

See also

• Tachograph - used on trucks.
• Flight data recorder - used on aircraft.