Bombardier TWINDEXX Double-Deck Trains

TWINDEXX is a double-deck train that is specially designed by Bombardier Transportation for Swiss Federal Railways (SBB). The rolling stock was designed in response to SBB’s proposals to launch an intercity high-speed express train. The trains proved to be the feasible choice for long-distance intercity transport on SBB’s existing routes with short platforms.

The train set provides excellent flexibility with its high capacity and easy-to-customise features. An added advantage is its compatibility to be operated with the double-deck engines of previous generations. Another special feature is its dual functionality to be operated as an EMU and as a locomotive.

TWINDEXX is successfully operated in countries such as Switzerland, Denmark, Poland, Germany, Luxembourg and Israel. Its operational speed is 160kmph to 189kmph, with a maximum speed is 230kmph.

In October 2011, Bombardier won the prominent "Tell Award" of Switzerland for its efforts in developing TWINDEXX trains and MITRAC propulsion and control system.

Design specifications of the TWINDEXX trains

The design specifications of TWINDEXX vary for intermediate coach and driving coach. The intermediate coach is 26.8m long, while the driving coach is 27.27m long. The coaches are, however, identical in height and width, which are 4,631.5mm and 2,784mm respectively. Entrance height above Top of Rail (TOR) for both the coaches is 600mm.

The train operates on 1,435mm (standard) gauge. Intermediate coaches have 121 seats, while driving coaches have 70 seats. Weight of the intermediate coach is 50t and that of the driving coach is 52t. Maximum axle load of both coaches is 18.3t.

Technology used in Bombardier’s double deck train TWINDEXX

The TWINDEXX trains consume 50% less energy than other comparable vehicles. This was achieved by using ECO4 technology and FLEXX Tronic WAKO system bogie technology, both developed by Bombardier.

FLEXX Tronic WAKO system is a part of Bombardier’s FLEXX Tronic bogie platform. The technology eliminates passive steering and suspension elements, which were the main drawbacks in the previous generations.

New functionalities such as active radial steering (ARS), active comfort improvement, tilting, bogie stabilisation and intelligent condition monitoring were included in the new car sets. These modifications enable higher trains speeds on curved tracks thereby reducing the train delays.

Three of ECO4 technologies namely MITRAC Permanent Magnet Motor, ThermoEfficient Climatisation System and Energy Management Control System were included in the TWINDEXX trains.

The MITRAC Permanent Magnet Motor reduces energy consumption and improves engine efficiency. It has an embedded motor cooling facility.

The ThermoEfficient Climatisation System also saves the energy consumption by its intelligent and flexible interior climate system. It manages to save up to 30% of the energy consumed for the cabin climatisation.

The Energy Management Control System offers a tool by which the operator can control the energy consumption depending on the prevailing conditions. These technologies improve the train’s performance, save 10% of total energy consumption and limit the CO2 emissions.

TWINDEXX variants

Bombardier is marketing TWINDEXX in two variants namely TWINDEXX Express and TWINDEXX Vario.

SBB was the first TWINDEXX Express customer. The variant can run at 230kmph. It is available in four, eight and 16-car configurations. The maximum drive power for an eight car train set is 7.5MW and overhead line voltage is 15 kV/16.7Hz. Door width for the variant is fixed at 1,400mm. The cars of the variant can also be used as cargo compartments, business compartments and trolleys for at-seat service.

Deutsche Bahn was the first customer for TWINDEXX Vario. The variant can travel with speeds ranging from 160kmph to 189kmph. It can be used as an EMU and Diesel Unit. It works on a 15kV/16.7Hz overhead line voltage with maximum acceleration of 0.6ms-2 to 1.2ms-2.

Maximum drive power of the variant is 2.3MW per motor cab. The lengths of control car, driven control car and intermediate car are 27.3m, 25.3m and 26.8m respectively. The widths of the doors are fixed at 1,300mm and 1,890mm for low entrance and high entrance respectively.

Features of the TWINDEXX trains

The TWINDEXX Vario comes with both low and high floor entrances, which enhances the accessibility of the passengers. The upper level decks can be accessed by means of brightly lit staircases. The advanced sliding steps will be of great advantage to people with reduced mobility.

All the car sets are air-conditioned and come with many optional features such as electronic seat reservations and seat numbers, reading lights, external loud speakers and mobile repeaters. Large-sized windows let in natural light to reduce artificial lighting by energy saving LED lights.

The high-speed TWINDEXX Express features wide entrances and illuminated stairs, huge baggage and bicycle luggage slots, comfortable first and second-class seating, on-board family restaurant, wireless internet access, electronic information system, closed circuit television, emergency call system and power sockets for mobiles and electronic devices.

The trains are designed to be pressure resistant, which eliminates ringing in ears due to pressure waves that are produced when the train is propagating in tunnels.

Orders and deliveries

In December 2008 a framework agreement was signed between DB and Bombardier Transport. DB placed a number of orders with Bombardier as part of this agreement.

A €362m ($483m) contract was placed in January 2011 for the supply of 137 Twindexx 2010 coaches by the end of 2013, as part of the agreement. In December 2011, 18 Twindexx Vario train sets were ordered additionally in a contract worth €34m ($44m).

In March 2012, a €160m ($210m) contract for supply of 16 four-car EMU’s was awarded by DB. These orders are expected to be delivered by 2014.

In October 2012, four and five-car EMUs were ordered in a contract worth €50m ($65m). These are scheduled for delivery by 2014.