Dr. Yellow: More than just good luck, it’s good maintenance

Dr. Yellow: More than just good luck, it’s good maintenance

Natalie Johnson
Posted 04/26/2023

Japan is known for their high-speed passenger trains, or Shinkansen. These bullet trains were first launched in 1964 prior to Tokyo hosting the Olympic games. Shinkansen is the world’s most reliable high-speed train network, and the railways are known for their high level of comfort, impeccable safety record, and on-time departures.

In the 59-year history of the Shinkansen there has not been a single accident or a passenger injury/fatality due to derailments or collisions. The trains average time of delay, per year, is consistently less than one minute and the trains regularly run at speeds ranging from 200-275 mph.

So how do they do it?

The key to maintaining the railways spotless record: Dr. Yellow

Dr. Yellow / Wikipedia

Along the railways, a unique bright yellow train can sometimes be seen cruising along. The rare sighting of this train is thought to bring good fortune and happiness to those who catch a glimpse as it flies by at 275 mph.

But the train brings much more than happiness and good luck. Dr. Yellow serves a very important function and is deployed every ten days or so to monitor the condition of the railway, running at the same speed and on the same rails as the normal bullet train.

The inspection vehicle is 7 cars long and contains sophisticated condition monitoring equipment that uses a series of cameras to record rail conditions for further review. Engineers on board analyze the footage for any irregularities in track alignment, wear or fraying in overhead wiring, and hazardous obstructions.

There are two inspections Dr. Yellow conducts:

  • Nozomi Inspection: Dr. Yellow runs on the high-speed lines of the passenger rails
  • Kodama Inspection: Dr. Yellow tests train stations where trains do not pass at high speeds

The nine-man crew, made up of two drivers, three track technicians, and four workers to analyze power-related issues, monitor the data collected from the condition monitoring equipment and relay the information to maintenance crews if a repair is necessary. The train is equipped with a GPS system, laser measurement, and a map-matching algorithm which pinpoints exactly where faults are located on the tracks.

The state-of-the-art diagnostic equipment also measures power outputs and vibrations, when an earthquake occurs, Dr. Yellow is immediately dispatched to inspect the tracks.

The unique color and sophisticated equipment allow Dr. Yellow to perform inspections day or night at the same speed as other bullet trains as to not interfere with regular train schedules. Dr. Yellow’s schedule is seemingly random and never made available to the public, making a sighting very rare.

Occasionally, the railroad company will hold a contest allowing winners to tour the train and view the maintenance equipment contained inside. In March 2023, the railroad company sold unique tickets allowing lucky passengers to take a short trip from Tokyo to Shin-Osaka Station on Dr. Yellow. In addition to riding on the train, passengers were able to view the test equipment and observation dome on the roof that inspects overhead wires.

Test Equipment / Backpackers
Observation Dome / Backpackers

If you are ever in Japan, keep your eye out, you might just gain good fortune as you see this yellow train flying by.

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Natalie Johnson

Natalie Johnson is the previous editor/website administrator for MaintenanceWorld.com, and is currently a student at Campbell University Norman Adrian Wiggins School of Law.

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Natalie Johnson

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