The use of a jumper wire that resulted in a false proceed signal is being blamed as the likely cause of the derailment of an Amtrak train last year near Niles, Mich.
The National Transportation Safety Board has ruled that the use of the jumper wire violated Amtrak procedures for overriding signal and train control safety. The NTSB also cited inadequate oversight by Amtrak management to ensure that proper jumper wire safeguards were used.
The accident occurred on Oct. 21, 2012, when Wolverine Service No. 350 en route to Detroit (Pontiac) diverged from the mainline at 61 mph at CP 190 and into the Niles Yard.
The train derailed about 291 feet after leaving the main track and traveled 1,148 additional feet before coming to a stop. The two locomotives, one on each end, and four passenger cars all derailed but remained upright.
The NTSB report said that a track maintenance crew had been operating a tamping machine at the site and after completing its work had contacted the Amtrak train director to seek permission to move the tamper into Niles Yard.
The train director was unable to align switch No. 2 into the yard and sought to contact a signal supervisor about the problem. However, no signal maintainers were available so a signal supervisor traveled to the site.
After arriving at CP 190, the supervisor attempted to correct the problem at the power-operated switch but was unsuccessful. He then entered the signal bungalow and removed two cartridge fuses, opened two terminal nuts on the terminal board, and applied local battery power using two jumper wires.
When the battery power was applied, the local control panel indication lights showed that the switch was aligned and locked normal, but he did not verify the physical position of the switch before applying the jumper wire.
The train director contacted the supervisor and informed him that the switch was now indicating normal on the dispatcher’s display and asked if it was safe for No. 350 to proceed eastward. The supervisor answered in the affirmative.
When the supervisor observed No. 350 approaching entering the yard tracks, he realized what had occurred, removed the jumper wires and reinstalled the cartridge fuses.
He did not notify anyone hat he had used jumper wires just before the derailment and he did not leave the signal bungalow to aid the passengers and crew on the derailed train.
On Oct. 26, 2012, Amtrak issued a safety notice and conducted a system wide safety stand down for signal maintenance personnel. Amtrak managers discussed the circumstances of the Niles derailment and reviewed proper jumper wire procedures at safety meetings throughout the system.
Amtrak also issued a safety bulletin that stated in part that that jumper wires should only be used as a last resort to restore train operations. The procedure requires the train director or operator to be notified in all cases in which any signal system is inoperative and how protection is provided until repairs are made and the jumper wires removed.