Social Shaping of Technological Trajectories of Shinkansen

Abstract

IntroductionThe Shinkansen, or bullet train, is a world-class Japanese innovation. The Tokaido Shinkansen began operating in 1964 and generated speeds exceeding 200 kmph, which were unheard of at that time for electric trains. This made it a global breakthrough. However, progress on the Shinkansen stagnated thereafter. After running on a provisional schedule for the first year in operation, the Shinkansen schedule was revised in November 1965. The service connected Tokyo and Shin-Osaka stations in 3 hours and 10 minutes at a top speed of 210 kmph. Because the Shinkansen competed with aircraft, speed improvements were essential. Despite this, the speed of the Shinkansen did not improve further until just prior to the splitting and privatization1 of Japan National Railways (JNR) in 1987.First, this paper overviews changes in various types of speed indicators for the Shinkansen. These speed indicators include maximum speed, scheduled speed, and test car maximum speed. The former two speeds are related to actual operations, whereas the latter is a proxy indicator of the technical limits. The maximum speed refers to the fastest speed logged within an operating section; the scheduled speed is calculated by dividing the number of kilometers travelled within an operating section by the time required to travel that distance (including the time required to stop at stations).Upon beginning operation in 1964, the Shinkansen ran on a provisional schedule in a wait-and-see approach; the scheduled speed was quite refrained, so even the express Hikari service between Tokyo and Shin-Osaka stations required 4 hours. The scheduled speed significantly improved in the following year with changes in schedule; subsequently, no changes were observed in both maximum and scheduled speeds until 1985. One may think that the reason for this is the lack of technological developments. However, according to Shinkansen professionals, increasing the speed itself was a simple matter. This can be verified by examining the transition of maximum speeds of test vehicles during the public railways era. Figure 1 provides a summary changes to these three speed indicators.Please note the trend indicated in the circle. We can discover the lack of increases until mid-1980s in scheduled and maximum speeds despite the maximum speed of test vehicles. The changes in schedule in 1985 and 1986 slightly improved the scheduled and maximum speeds; subsequently, these speeds rose dramatically in the first half of the 1990s. Given this, the following two research questions are considered.RQ1: no parallel efforts were made to improve speed related to speed improvements of test cars and operation?RQ2: How were factors preventing the incorporation of technical progress into operations eliminated?This paper responds to these research questions in order.Factors Preventing Technical ProgressThis section considers the first research question, Why no parallel efforts were made to improve speed related to speed improvements of test cars and operation? Primarily inhibiting factors that were uncovered in the study include 1) environmental issues and 2) labor issues.1. Environmental issuesBecause the Shinkansen operates at speeds exceeding 200 kmph and sprints through Tokyo, Nagoya, Osaka, and other areas, which are dense in population, noise pollution is a serious problem. Similar to air and water pollution that became an issue in Japan in the 1970s, noise pollution was considered to be an emerging issue. Thus, regulations were set for noise pollution in 1975 based on Basic Law for Environmental Pollution Control. During that time, noise pollution levels were set at 70 dB or less when passing through residential areas, with a goal of achieving this level by 1985. When measuring the noise of the Tokaido Shinkansen in 1973, levels varied widely by location but were generally in the range of 80 to 100 dB. …