EAST JAPAN Railway's Fastech 360 S and Fastech 360 Z may be twins, but they are far from identical. The two sisters met for the first time on March 10, when Fastech 360 Z, officially designated as Type E955, arrived at its future home, the Shinkansen General Rolling Stock Centre in Sendai.
The Centre is a 3·6 km long complex that looks after major overhauls and heavy maintenance for JR East's entire Shinkansen fleet of 1130 vehicles, sharing the task with seven other depots and workshops that undertake daily inspections, cleaning and routine maintenance. The Centre's role includes testing and evaluating the two Fastech 360 trainsets over the specially equipped section of the Tohoku Shinkansen between Sendai and Kita Kami. Changes on this 120 km section include the use of chimneys near the entrance of the 9·7 km Ichinoseki tunnel to mitigate the effects of micropressure waves generated as the train enters the bore. On the section where speeds are highest, the catenary tension has been increased to 19·6 kN, while new types of lineside sound barrier have been fitted in selected locations.
From June to August last year the tests with Fastech 360 S focused on running stability, and from September to November attention switched to noise and the environment. The aim is for the Fastech trains to make no more noise at 360 km/h than a Hayate Series E2 at 275 km/h, but so far this objective has not been attained. A number of modifications have been made, including changing the design of pantograph shield from the original curved shape to straight-sided panels.
The intention is to reduce to the absolute minimum the number of noise sources on the exterior of the train. Even the recesses containing the grab handles by the doors to the driving cabs have covers that slide into position once the train is moving.
Future trials will involve both trainsets, including passing tests with a closing speed of 720 km/h. The trials will continue until the end of 2007, but JR East hopes to take a decision on whether to proceed to a series build by the end of this year.
Asked if JR East plans to try and capture the Japanese speed record, the General Manager of the Technology Planning Department Takashi Endo, who is also Director General of the company's R&D Centre, says the principal objective is to be able to achieve stable and reliable running with the Fastech 360 trains, but 'an attempt on the speed record is not ruled out'.
Mini-Shinkansen
The S in Fastech 360 S (RG 11.05 p693) stands for Shinkansen and the Z in Fastech 360 Z for Zairaisen, the Japanese word for a conventional line. This indicates that Fastech 360 Z is able to run on routes that have been converted from 1067mm to 1435mm gauge - commonly known as mini-Shinkansen lines. The Z train will be tested on the mini-Shinkansen route from Morioka to Akita.
On March 26 Fastech 360 Z moved under its own power in the depot confines for the first time, and by April 5 JR East was confident enough to present the six-car trainset to the Japanese media. The train had arrived by ship at Sendai port, with four cars making the journey along the coast from the Kawasaki Heavy Industries plant in Kobe, and two from Hitachi's factory at Kasado in western Japan.
Although outwardly similar and finished in the same attractive livery of pearl white and 'East Green', there are significant differences. The body width of the Z train is 2904mm compared with 3380mm on the Fastech 360 S. According to Fastech Project Manager Naoki Kobayashi, this was a considerable challenge for the design team who had to accommodate the same equipment as on the S train in a smaller space. Air-conditioning and other equipment was located on the roof of the small-profile Series E3 Komachi trainsets, but this was ruled out for the Z trainset, and the equipment was mounted below the floor.
Fastech 360 S has different front ends to test the most effective aerodynamic performance. One end car has a 'stream' nose and the other an 'arrow-line'. On Fastech 360 Z both end cars adopt the arrow-line shape, which was found to perform slightly better. One car on the Z train has a 16m long taper and the other a 13m taper.
Both trains have longitudinal noise shields flanking the pantographs, but those on the Z train are designed to retract into pockets in the side of the body when running on the mini-Shinkansen route from Morioka to Akita, where they would infringe the loading gauge. Top speed on this line is in any case limited to 130 km/h.
Bogies
On the Fastech 360 S both end cars are unpowered. With the Z train, the inner bogie of the end cars is powered.
Changes have also been made to the bogies so that the train is better suited to the sharp curves of the former narrow gauge line. Achieving this compromise was a challenge to the bogie designers, and three different types of bogie are being tested. The bolsterless bogies have sensors installed to monitor performance in real time, and this information is displayed on a screen in the driver's cab.
A related development is the use of yaw dampers with two settings. When running on the Shinkansen, a high damping coefficient is set to give good running stability at high speed. On the mini-Shinkansen a low damping coefficient is set to ensure a smooth passage through the relatively sharp curves.
Both trains also have active suspension, as first introduced on the Series E2 Hayate trains. Whereas the E2 used a pneumatic actuator in the linkage between the body and the bogie frame, the actuators on the Fastech 360 are electromagnetic.
Tilting bodies
Both trains have a tilting system with a maximum tilt of 2°, with two types fitted to the Fastech 360 S for comparison. One was supplied by Sumitomo and the other by Kawasaki Heavy Industries.
Another physical difference is the flexible fairings between the ends of the intermediate cars that smooth the passage of air over the gap. On the Fastech 360 S these fairings are made of a solid material in three sections, the centre one of which folds inside the others as the train passes through a curve.
Bodies on Fastech 360 Z are constructed using a double-skin aluminium design with equipment modules integrated with external panelling along the lower part of the car below the floor. The lower panels, as on the sister train, feature a honeycomb construction which is designed to absorb wheel-rail contact noise reflected off the lineside sound barriers.
Traction packages
The restricted space available prompted JR East to test two different traction packages which are intended to be compact and lightweight. Cars 11 to 13 use three-phase squirrel-cage induction motors with a nominal rating of 370 kW, while synchronous motors rated at 355 kW are installed on Cars 14 to 16. Total nominal output is 7250 kW. As on the 360 S a double helical gear which does not produce any axial force during torque transmission is used instead of conventional helical gears, so reducing the load on the bearings.
The two single-arm pantographs have multi-segment sliders which help ensure that good contact is maintained; a small spring supports each segment.
Interior design
Fastech 360 S is fitted with a variety of interior features from leading industrial designers in five of the eight cars, together with several different types of seating and three types of window. Bright colours, including an entire car of strawberry red seats, another with black seats and light lime antimacassars, have been used to test reactions from passengers.
The Z train tests different interior concepts that would be considered more tasteful by conservative passengers. Endo says that he is keen to appeal to young people, and for this reason he is involving teams of young industrial designers in the development of both the Fastech 360 trainsets.
One of the six cars on the Z train is designated a 'special' car with seats for 25 people and a distance between seats of 1160mm compared with 980mm on the other cars. On Fastech 360 S the distance between seats varies, with different cars featuring seats that are 980mm, 1000mm, 1040mm and 1160mm apart.
- CAPTION: MAINPICTURE:The Fastech 360 S is now undergoing daytime trials at up to 320 km/h. Speed during testing at night has reached 398 km/h
- INSET ABOVE: As with the Fastech 360 S, the Z train has aerodynamic resistance boards that can be raised from the roof. They are intended to ensure the same stopping distance from 360 km/h as for a Series E2 trainset from 275 km/h and are intended for use in emergencies such as an earthquake
- BELOW: Only two of the six cars of the Fastech 360 Z prototype are fitted with seats. Testing and monitoring equipment occupies the other four
- CAPTION: Fastech 360 Z moved under its own power at JR East's General Rolling Stock Centre in Sendai on March 27
- 1. Driver's cab of the Fastech 360 Z occupies a narrow space in the 'arrow-line' nose Photo:Mikio Miura
- 2. Green car seating for the Fastech 360 Z is being tested in the S train
- 3. The lower bodyside panels on both Fastech 360 trains are made of sound-absorbing materials intended to absorb wheel-rail noise bouncing off lineside sound barriers
- 4. Jets beside the wheels apply ceramic powder to increase adhesion during emergency braking
- 5. The pantograph shields on Fastech 360 Z retract into the body as they would infringe the loading gauge on mini-Shinkansen lines
