The occurred on November 9, 1963 between Tsurumi Station

Tsurumi Station

is a railway station operated by JR East located in Tsurumi-ku, Yokohama, Kanagawa Prefecture, Japan. It is an interchange between the Keihin-Tōhoku Line and the Tsurumi Line , and is 52.0 kilometers from the terminus of the Keihin-Tōhoku Line at Ōmiya Station...

 and Shin-Koyasu Station

Shin-Koyasu Station

is a train station operated by East Japan Railway Company located in Kanagawa-ku, Yokohama, Japan.-Station layout:The station is a two-storied station structure with an island platform serving two tracks.-Platforms:-External links:*...

 on the Tōkaidō Main Line

Tokaido Main Line

The is the busiest trunk line of the Japan Railways Group , connecting Tōkyō and Kōbe stations. It is long, not counting its many freight feeder lines around the major cities...

 in Yokohama

Yokohama

is the capital city of Kanagawa Prefecture and the second largest city in Japan by population after Tokyo and most populous municipality of Japan. It lies on Tokyo Bay, south of Tokyo, in the Kantō region of the main island of Honshu...

, Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

, about 30 kilometre south of Tokyo

Tokyo

, ; officially , is one of the 47 prefectures of Japan. Tokyo is the capital of Japan, the center of the Greater Tokyo Area, and the largest metropolitan area of Japan. It is the seat of the Japanese government and the Imperial Palace, and the home of the Japanese Imperial Family...

, when two passenger trains collided with a derailed freight train, killing 162 people.

Accident

The 43rd wagon of a long freight train on the down-freight railway derailed and the two following wagons overturned, blocking the adjacent "up" passenger railway. Within seconds, a 12-carriage EMU train traveling to Tokyo collided with the freight wagons and the front three carriages derailed, falling into the side of the fourth and fifth carriages of another 12 carriage train passing on the down-line to Kurihama. The multiple collision left 162 dead and 120 injured.

Investigation

The initial JNR investigation found that the speed of the freight train (60 km/h) was not excessive, nor were any problems found with the line or rolling stock. For five years, the RTRI carried out tests on a test track using the same rails and rolling stock and found that the combination of wheelset design, rail cross section and wear, and track geometry all had a role in the derailment. As a result of the investigation, the old method of static track inspection was replaced with new track inspection cars employing dynamic inspection methods and data collection.