INTRO: Roger Ford believes that body tilting has become a low risk bolt-on extra with provision for future retrofitting adding little to initial costs
A CONFERENCE hosted by Britain’s Institution of Mechanical Engineers in January brought together presentations on all the European tilt technologies. While aimed at the renewed interest in tilting trains among the privatised passenger train operators in Britain, the conference underlined the fact that tilt has come of age worldwide.
In particular, train operators now regard tilt as an optional extra rather than a novel technology with which to experiment. At the same time, the equipment has become more compact, allowing trains to be designed for future upgrading with little adverse impact on passenger accommodation, performance or cost.
An early example of this was British Rail’s MkIV coach designed for 225 km/h, and intended to be the standard InterCity vehicle when it was ordered in 1986-87. These vehicles have tapered bodysides to remain within the loading gauge when tilted, although the only ones built - for IC225 formations on the East Coast main line - were not fitted with tilting equipment.
More recently, the three-car EMUs for Norway’s Gardermoen Airport line are tilt-capable, but only the last of the 18 sets ordered from Adtranz will be so fitted. However, a batch of 14 four-car inter-city units to essentially the same design ordered by NSB will have tilt from the start.
In the case of the Gardermobanen trains, the new line is relatively straight, making the benefits of tilt marginal when compared with the 5% to 10% cost differential. However tilt will show significant reductions in journey time elsewhere on the NSB network.
Technology is also favouring the concept of tilt as a ’bolt on extra’. Responding to commercial demand, rolling stock manufacturers have moved an increasing proportion of the tilt hardware underfloor. For example, in its third generation of tilting technology Fiat Ferroviaria has eliminated the protrusions into the passenger accommodation which housed tall vertical springs in the original Pendolinos.
While Fiat comfortably maintains its lead in terms of applications and number of vehicles built - or fitted with bogies and tilt mechanisms subcontracted to other manufacturers - another indication of the maturing technology is the recent rapid development and commercialisation of electric actuation, as opposed to hydraulic or pneumatic.
Significantly, both of the electro-mechanical systems now commercially available use hardware and control software derived from existing armoured fighting vehicle gun stabilisation platforms.
Because of environmental concerns over the potential hazards of leaking hydraulic fluid, German Railway specified electric tilt for the VT611 and 612 diesel multiple-units it ordered from AEG, now owned by Adtranz. While the VT611 suffered teething troubles following its entry into service just two years after the contract was awarded, the tilt system does not appear to have been the main cause of these problems.
SIG, now owned by Fiat, has run a test train fitted with its electric tilt system which is to be used on the Swiss Federal Railways’ IC Neitech trainsets being built by an Adtranz / Schindler / Fiat-SIG consortium.
There has been a marked concentration of tilt technology as European industry continues to rationalise. Within Adtranz, ABB which produced the hydraulic tilt for the Swedish X2000 joins electric tilt newcomer AEG. Similarly, Fiat has added SIG’s electric tilt capability to its own hydraulic tilt experience with the Pendolino series.
This left the other two major European electrical suppliers, GEC Alsthom and Siemens, with the choice of forming partnerships or starting their own in-house development.
Faced with the politics of the North American market, GEC Alsthom formed a consortium with Bombardier to supply the American Flyer tilting trains for Amtrak. Tilt systems are being supplied by Bombardier, using an updated version of the hydraulic tilt equipment fitted to VIA Rail Canada’s LRC fleet.
About 100 LRC vehicles are still in service, although most are no longer hauled by the original power cars. One set has been fitted with a digital electronic control system, under development since 1986, which will form the basis for the American Flyer tilt equipment. American Flyer will feature TGV type bogies fitted with Bombardier hydraulic-powered tilt, but acting on swing links rather than the bell cranks used on the first LRC.
With SNCF now looking to tilt as a way to improve journey times to regions unlikely to benefit from a scaled back Master Plan network of high speed lines, GEC Alsthom will fit tilt gear to a shortened first generation TGV set to gain experience. GEC Alsthom and Fiat have also been in negotiation over collaboration in Britain, where Virgin West Coast is set to be the next major customer for a fleet of high speed tilting trains (p216).
Siemens has started to establish its own tilt capability, following its use of the Fiat bogies and hydraulic tilt packs for the electric IC-T fleet to be delivered to DB from May 1998. DB has asked Siemens to switch to electric tilt for the 20 IC-T VT diesel inter-regional trainsets which are due to follow IC-T off the production line in May 1999. The company has therefore started to develop its own electro-mechanical system at its ’centre of competence’ for bogies in Graz, and prototypes are now on test .
Tilt at lower speeds
Another indicator of tilt’s mainstream technology status is that applications outside the high speed market are multiplying. Early examples were DB’s VT610 regional diesel multiple-units.
Bombardier Prorail is now seeking to widen the market further with a simple tilt system which eliminates complex bogie linkages and uses hydraulic actuators connected directly to anti-roll bars on the vehicle’s suspension. Conventional anti-roll bars are designed to prevent the vehicle from leaning outwards on its secondary suspension under centrifugal force generated when curving. The Bombardier system detects that the vehicle is curving and uses the powered anti-roll bar to lean the body into the curve.
Tilt is now following the pattern of other innovative technologies; introduced as an expensive option at the premium end of the market, subsequent developments are becoming standard equipment throughout the product range. o
CAPTION: FS and SBB officials at Bellinzona on January 11 celebrate the first day of Milano - Zürich Cisalpino services using the fleet of nine ETR470 sets built by Fiat/Schindler
CAPTION: While Norway’s Gardermobanen trainsets are derived from the successful X2000 design used in Sweden, most will not be tilt-fitted due to the straightness of the new line; 14 similar trains to be built for NSB’s often tortuous inter-city routes will have tilting equipment from the outset, as the extra cost can be justified
CAPTION: Following a batch of 20 two-car DMUs for regional services around Nürnberg, with tilt based on Fiat’s Pendolino, DB ordered 50 VT611s with electric tilt gear from AEG (now Adtranz). These will be followed by another 50 tilting DMUs, designated VT612
CAPTION: JR Kyushu’s Series 883 Wonderland Express tilting trains have cut limited express timings between Hakata and Oita
TABLE: Table I: Trains with active tilt systems in service or on order
Railway Builder Class Formation Number of vehicles
1990 1995 1997 2000
a) with Fiat tilt technology
FS Fiat ETR450 15 x 9-car 135 135 135 135
Fiat ETR460 10 x 9-car - 90 90 90
Fiat ETR480 15 x 9-car - - 135 135
Cisalpino AG (FS/SBB) Fiat/Schindler ETR470 9 x 9-car - - 81 81
DB Consortium VT610 20 x 2-car DMU - 40 40 40
DB Siemens IC-T 32 x 7-car }
" 11 x 5-car } - - 279 279
SBB Consortium 1 IC Neitech 24 x 7-car - - 168 168
VR Fiat S220 2 x 6-car 2 - 12 12 12
CD Siemens/CKD Integral 10 x 7-car - 70 70 70
Renfe GEC Alsthom/Fiat IC 2000 10 x 3-car - - 30 30
CP Siemens/Fiat Pendolino 10 x 6-car 60 60
KTM Berhad Fiat Pendolino 7 x 6-car 3 - - 42 42
Subtotal: On order - 70 784 -
In service 135 277 358 1142
b) with Adtranz tilt technology (ABB/AEG)
SJ ABB X2000 Various 4 100 142 237 237
DB AEG VT611 50 x 2-car DMU - 100 100 100
Adtranz VT612 50 x 2-car DMU - - 100 100
Subtotal: On order - 100 100 -
In service 100 142 337 437
c) with Bombardier tilt technology
Via Rail Canada Bombardier LRC Various 5 100 100 100 100
Amtrak Bombardier/ American
GEC Alsthom Flyer 18 x 8-car 6 - - 162 162
Subtotal: On order - - 162 -
In service 100 100 100 262
d) with Hitachi tilt technology
JNR } Series 381 30 x 9-car EMU 7 268 268 268 268
JR-Shikoku } Series 8000 15 x 3-car EMU - 44 44 44
JR-Shikoku } Series 2000 20 x 3-car DMU 58 58 58 58
JR-West } Various 8 Series 281 1 x 3-car DMU - 3 3 3
JR-East } Series 961 2 x 12-car EMU - 24 24 24
JR-Kyushu } Series 883 14 x 5-car EMU - 70 70 70
JR-Central } Series 383 13 x 3-car EMU - 80 80 80
Queensland Railways Walkers/Hitachi - 2 x 6-car EMU - 12 12 12
Subtotal: On order - 162 12 -
In service 326 397 547 559
e) with Siemens tilt technology
DB Siemens IC-T VT 20 x 6-car DEMU - 120 120
Subtotal: On order - - 120 -
In service - - - 120
TOTAL: On order - 332 1184 -
In service 661 916 1342 2520
TABLE: 1. Adtranz/Schindler/Fiat-SIG
2. Plus option for 23 sets
3. Plus option for 15 sets
4. 20 x 6-car, 14 x 4-car, 7 x 5-car, plus 26 spare vehicles, excluding non-tilting power cars5. Approx 100 coaches, plus 32 power cars
6. Six trailers and 2 power cars per set
7. ’Natural’ (passive) tilt only8. Most Japanese tilting trains are supplied by a group of manufacturers drawn from Kawasaki, Nippon Sharyo, Tokyu Sharyo, Hitachi and Mitsubishi
Tilt nausea is bad business
YOUR editor recently had the opportunity to ride a Cisalpino tilting train between Sion and Lausanne. It was by no means his first tilting train trip, as he had previously ridden on Italian State Railways’ ETR401 prototype and on both ETR450 and ETR460 Pendolino units. He has also experienced the X2000 in Sweden, the LRC in Canada, Series 381 in Japan, and tilting Talgo trains. Most memorable of all the tilting train trips was on the inaugural run of Britain’s Advanced Passenger Train on December 7 1981, when the train whisked fare-paying passengers from Glasgow to London in 4h 14min.
Tilt nausea was recognised as a potential problem in the early days of tilting trains in the 1970s, but your editor has never suffered serious problems. Racing up the old and sharply curved line between Roma and Chiusi in the ETR401 on a demonstration trip was an experience that made a number of passengers feel mildly nauseous, but the train was running at higher speeds than envisaged in commercial service. The sensation was most acute when walking along the train. On the APT the queasy effect was not felt while the train ran in the early morning darkness, but it was quite noticeable in the daylight later in the journey. Roger Ford, editor of our fortnightly newsletter Rail Privatisation News, also found that walking along an X2000 tilting train moving at high speed caused similar feelings of discomfort.
So much for the professionals. Less seasoned travellers may suffer more. On the Cisalpino, your editor was accompanied by his wife and two daughters, who all enthused over the train’s exterior and interior design. The euphoric feeling on the first part of the trip along relatively straight alignments vanished rapidly as the train followed the rapid succession of curves along the shore of Lac Leman. Although the party remained seated, they were smitten by acute discomfort. By the time the train drew up at Lausanne, it was too much for the daughter aged 12, who regrettably suffered loss-of-breakfast syndrome immediately after alighting. Later, we were asked: ’Will you promise not to take us on a tilting train again?’
Richard Branson and others enthused by the tilt train concept should take note. Shorter journey times will bring more business, but the price of tilt nausea should be factored in. o