The TGV Paris Sud-Est

Introduction

This was the first operational high-speed line in europe, between France's two largest cities. It opened in 1981 with TGVs that ran regularly at 270km/h (168mph) and cut the journey time between the two cities from 4hours 30 minutes to 2 hours.

History of the line

In the 1970s SNCF, the French State Railays, was experiencing growth at a modest rate on its Paris-Lyon-Medditerannée (PLM) line. This was a strategically important line, service 40% of France's population. Although for most of its length it consisted of four tracks, it was predicted it would soon reach its maximum capacity. Also speed improvements were sought as SNCF wanted to become more competative. The existing line was cleared for running at 100mph (160km/h). A possibility would have been to upgrade this to 125mph (200km/h) and also upgrade the two-track sections to four-track sections. However, since many of the two track sections were in tunnels, the cost of doing so would have been prohibitive, and it studies concluded that it would be only 40% as expensive to build a compeletley new line, and this would have the added advantage of being able to allow speeds much higher than 125mph (200km/h).

Route Information

The line starts outside of Paris, and runs directly to the edge of Lyon. To travel into the city centers the TGV runs on existing track but at conventional train speeds. About half way down there is a branch off into Dijon, where trains come off the high speed line, and run on conventional track to Dijon and then on into Switzerland. However, once off the Paris-Lyon line, these trains are limited to conventional running speeds. Similarly many trains continue south of Lyon on existing track to the South Coast, although a new high speed line is being built now.

Technical Information

The TGV Sud Est was designed for 300km/h (186mph), although the current maximum is 270km/h (168mph). This at the time of construction was faster than any other service in the world. The maximum gradient was to be 3.5%, or 1 in 28. This is quite steep for a railway, however, it meant there was no need for tunnelling and greatly reduced costs. In any event, TGVs have enough power to cope with these gradients. Maximum axle loading was limited to 17 tonnes, meaning TGVs had to be lightweight trains, to help reduce track wear. Gentle Curves were required for such fast running, so the line has a minimum curve radius of 4km (2.5miles)

Economic effects

The line was a financial success. The SNCF financial rate of return on was 15% per year , and the rate of return was estimated at 32% when counting social benefits. The line paid for itself in less than ten years. Rail patronage was up by 500%, airlines lost about 40% of their passengers between Paris and Lyon and road traffic between the cities dropped by 30%. This success story spurred a great deal of interest in high speed rail.