Advanced passenger train

The Advanced passenger train ( APT ) is a pendular Train developped at the point by British Rail in the years 1970 - 1980, which was a technical and commercial failure.

Context

In Great Britain, only the line of the east coast, the East Coast Hand Line , connecting London to Edinburgh has a layout rather rectilinear and adapted to raised speeds, the majority of the other lines, and in particular that of the west coast, the West Coast Main Line of London with Glasgow, are too sinuous to accept the speeds raised in traditional material. The Dévers applied to the way in the curves authorizes a speed of 160 km/h (100 mph), but not more.

To reach a speed of 240 km/h (150 mph), essential to improve the commercial performance, the engineers of British Rail developed with the workshops Derby a advanced technique of active pendulation, using hydraulic actuating cylinders ordered by Ordinateur so as to incline in the curves the cases of the cars of travellers so that the side forces are not felt. In 1972, the experimental oar SUITED, equipped with a Gas turbine, was built. It comprised only four cars, two motor coaches at the ends and two cars intermediate faggots of measuring instruments.

This experimental train having made it possible to validate the concept, British Rail decided to build three oars prototype S, APT-P, Classe 370. The propulsion by gas turbine was abandoned, as well for too strong consumption as because of the crisis of the oil of the years 1970, with the profit of the electric traction, although that limited the circulation of these machines to the only electrified lines, still little extended in the country.

At the time, the pantograph S did not make it possible to collect the current at the two ends of the train at the speeds considered. The trains were thus composed of two coupled oars, with two motor coaches twinned in the medium, dividing only one pantograph. There was a communication between the two motor coaches, but impracticable for the travellers, which forced to equip each oar with toilets.

The premature launching of the train in 1981, whereas it was far from being ready on the technical plan, involved many problems and an insufficient reliability.

Pendulation and badly of transport

At the time of the first voyage of demonstration, journalists felt the evil of transport (Cinétose), and that made a very bad publicity with the project. One realized that a perfect compensation of the centrifugal force could generate kinetosis because the passengers could see the curve of their eyes without feeling it in the body. One cured it by limiting the slope of a few degrees so that the curves are nevertheless felt.

Certain cars knew breakdowns of pendulation during this first voyage. Moreover very cold time caused other problems, and the trains were withdrawn from the service four days later.

This highly visible failure was the reason of the final failure of the project.

Startup, and end of the project

The trains were given in service discreetly to the summer service 1982 and circulated regularly, the defects having been corrected. But the will of the company and the political circles to continue the project by building the version APT-S had disappeared.

Two of the trains were reinforced and the third garaged on a siding behind the workshops of Crewe Works. It is currently presented to the Musée of the railroads of Crewe.

APT and TGV

Contrary to the APT, TGV French, developped at the point appreciably at the same time, was a great success.

the SNCF had not only concentrated on rolling stock, but also on the infrastructure on which it was to roll. It was directed towards the construction of news lines at high speed, especially conceived for high-speeds, without tight curves and not requiring complicated systems of pendulation.

This solution would have however been more complex to bring in work in Great Britain to the level of the public surveys and because of the opposition of the residents, coma showed it the experiment of the Chanel Tunnel Rail Link (CTRL, line new London Tunnel).

The French had also solved the problem of food, thanks to the installation of a feeder to high voltage on the roof of the oars, allowing to supply the motor coach of head since the back pantograph.

Pendular technology in Italy, and Europe

The technology developped at the point for the APT was re-used in Italy by the subsidiary company FIAT ferroviaria for the design of the Pendolino . The Pendolino system has had for summer sold with many networks with the international plan, of which in Great Britain the oars Classe 390 introduced for the modernization of the West Coast Main Line.

These oars of Italian design (whose ETR 460) were brought into service starting from end 2003. Since September 2004, all the schedule of Manchester and Birmingham towards London Euston is ensured by these trains.

FIAT ferroviaria is also at the origin of the pendular oars S220 developped at the point by the Rautaruukki-Transtech company (repurchased since by the Spanish group Talgo) to be used in Finland.

Alstom since repurchased (in July 2000) FIAT ferroviaria, re-elected in " Alstom ferroviaria".

Internal bonds

External bonds

A semi-official page on the APT (in English)

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