Two new EMU designs are being developed for use by independent operators bidding to run regional concessions in Europe. Harry Hondius reports

PLANS TO DEVELOP a new modular platform for regional EMUs were announced by Siemens Transportation Systems at Uerdingen on June 23.

STS expects to see operating contracts put out to tender for 90% of regional routes in Germany, triggering a substantial demand for new rolling stock that could match the bulge of investment seen on regional services tendered over the past decade.

However, DB will not permit the three big manufacturers to sell EMUs to its domestic competitors based on the successful ET 423-426 family. As a result, Stadler Pankow has taken orders from various German operators for 61 Flirt articulated EMUs, ranging from two-car to five-car sets. FTD of Dessau is also moving into the market with its Protos design.

After a thorough analysis, Siemens has decided to develop a new EMU family, known as Desiro Main Line. It will offer two, three and four-car sets with between 120 and 384 seats. Articulation is out; each car will be carried on two separate air-sprung bogies. End cars of 24m and 22m intermediate vehicles will be coupled to form units of 48·5, 70·9 or 93·3m.

Depending upon the interior configurations, these will accommodate 120 to 184, 184 to 284 or 248 to 384 seats respectively. There will be a driving motor car, driving trailer and intermediate trailer; four or five-car sets would have two motor cars.

The cars will have integral welded modular aluminium bodyshells, meeting the current TSI requirements for buffing loads, crashworthiness and accessibility. The trains will be offered with floor heights of 600, 800 or 1000mm above rail to suit variations in platform height. A retractable step will be provided for stations with 380mm high platforms. Cars with 600 and 800mm floor heights can have two 1300mm wide doorways per side, the higher version can have four. Inter-car gangways will be 875mm above rail.

Each motor car will have four semi-suspended 325 kW asynchronous motors, giving a typical acceleration of 1m/s2. Regenerative braking will also be offered as standard, together with disc brakes and magnetic track brakes. The air-conditioning equipment will be roof-mounted.

The traction package has been designed to work on all four European voltages and the units can be fitted with various signalling and ATP systems. Provision has been made for the installation of ETCS equipment and video monitoring systems if required.

Desiro Main Line in figures

ProfileUIC 505-1
CrashworthinessprEN 15227:2005
Fire protectionprEN45545
Platform heights mm550, 760, 900
Minimum radius m110
Operating temperature range íC-25 to +40
Car width mm2840
Car height mm4250
End couplersScharfenberg
Buffing load kN1500
Bogie centres
end cars m16·2
centre cars m15·5
Wheelbase mm2 300
Wheel diameter (new/used) mm850/760
Tare weight, tonnes
for 15 kV power car46
for driving trailer35
for intermediate trailer33·5
Maximum axleload tonnes16·5
Weight kg/m2
Power-to-weight kW/t