While shinkansen are renowned for their advanced automatic control systems, confidence in the trains may have gone too far Saturday as a driver left his cab for five minutes, Central Japan Railway Co. (JR Tokai) revealed Tuesday.
The train traveled about 2 km from Tokyo's Shinagawa Ward to Tokyo Station without a driver.
Shortly after the train left Shinagawa Ward at 7:05 a.m. Saturday, the 50-year-old motorman realized he had lost his cap and walked toward the rear of the 16-car train to look for it, JR Tokai said.
No passengers were aboard as the train was deadheading, no accidents ensued and the motorman eventually found his cap by a sink in the second carriage from the front of the train, JR Tokai said.
The train was moving at around 25 kph at the time. Railway officials noticed something was wrong as the train passed a signal two minutes behind schedule and reached Tokyo Station one minute late.
The driver, who has 17 years' experience, told his story while being questioned by supervisors late Saturday night, JR Tokai said.
He said that while he had reservations about leaving his seat, he was concerned that his cap was missing, according to company officials. It is against company rules to work without a cap on.
Bullet trains are controlled by the Automatic Train Control system, which limits speeds. Shinkansen tracks are also enclosed within high fences as a safety measure. Despite this, leaving the controls unattended is prohibited, and the carrier will punish the driver, JR Tokai said.