Locomotives vs. multiple units
First things first, some definitions:
- Locomotive: an autonomous powered rail vehicle for traction, carries no passengers or cargo
- Railcar: an autonomous powered rail vehicle carrying passengers or cargo
- 'Normal' train: locomotive(s) pulling (one or several coupled) unpowered cars (a "consist")
- Multiple unit: an autonomous consist of permanently coupled cars, of which one, more, or all could be powered
- EMU, DMU: electric resp. diesel multiple unit
- Powerhead (tractor head): powered end car of a multiple unit that carries no passengers or cargo
|Nearing on the left: locomotive ÖBB [class] 1116 [no.] 215 heads ÖBB EC 262 to Munich. Receding on the right: ÖBB 4024 110, an articulated four-car EMU, in service on Salzburg's S2 rapid transit line.|
Choice was for long (and is) a dilemma. On one hand, the advantages of multiple units are:
- less aerodynamic resistance (and thus noise)
- lower weight (and train length, especially if power equipment is underfloor)
- higher acceleration (if enough cars are powered)
- quick reversal at terminals
- more spacious, even doorless gangways between cars
...on the other hand, the advantages of locomotive-pulled trains are:
- cheaper (and quicker) production
- easily variable train length (by addition/removal of cars)
- consequently, maintenance is also simpler (and cheaper)
- high utilisation (loco can be put to another use even when the cars are serviced)
|Another look at ÖBB 1116 215 with ÖBB EC 262: the locomotive is one designated and painted for railjet service.|
This dilemma led railways to swing their preference either way several times.
Just in the field of express service: the first speedy multiple units (Fliegender Hamburger & co) were the stars of the thirties, but soon hit a capacity problem. Then, in the late fifties/early sixties, multiple units had a renaissance in TransEuropExpress service, until capacity and maintenance issues brought locos back again by the seventies.
But then for high-speed trains, EMUs seemed to have won decisively: aerodynamics and weight were very strong benefits, while streamlined full-train maintenance reduced that disadvantage. Thanks to the new asynchronous motors from the eighties (which allow continuous acceleration), EMUs/DMUs also gained an edge in rapid transit/commuter rail (though push-pull trains with locos and double-deck cars could keep up in efficiency).
Now, why is ÖBB running against the trend?
That it can even consider locomotives is due to lack of demand for a truly high-speed train: Austria has no plans for 300 km/h lines, its biggest project is the four-tracking of the busy Westbahn from Vienna to Salzburg, with two tracks for 200 km/h.
Before I give the real answer, first let me blur that nice contrast between distinct categories I established in the previous section.
Enter driving trailers: put a cab that remote-controls the loco at one end of a car, put that car at the train end opposite the loco. You gained multiple unit benefit #3 (quick reversal) at the cost of losing normal train benefit #2 (add/remove cars). But driving trailers are ever more popular with railways, recently spreading up to locomotive-pulled express trains.
|ÖBB IC 693 (with the idiotic sponsored name "betriebliche-altersvorsorge.at"), though an entirely domestic train from Klagenfurt via Salzburg to Vienna, is run with a complete German Railways (DB) train. The morning Sun glimmers on the leading driving trailer near Bad Vigaun, just the morning when the artic cold spell peaked here (it must have been -15°C, I learnt only after my return home).|
The three locomotive-pulled trains built for speeds above 200 km/h go even further.
- The British InterCity 225, built for 225 km/h though operating only at 200, is headed by asymmetric locomotives (Class 91): one end is (more or less) streamlined, the other flat. Almost like the powerhead of an EMU, except for lack of permanent coupling and cabs at both ends (though it rarely pulls trains flat cab ahead).
- In Spain, local maker Talgo specialised in the production of articulated trainsets: these are light, smooth running, lack gangway doors, and are permanently coupled by nature. Almost like the middle cars of a high-speed EMU with powerheads (indeed the company needed to add little else for the Talgo 350 high-speed train). Class 252 locos pull Talgo VII sets at up to 220 km/h. (See pictures of both such a train and a Talgo 350 in High-speed to Barcelona.)
- A recurring dream of railway execs that just refuses to die is an exclusive elevated-comfort train for business travellers, despite zero success stories and several failed attempts. One of these was German Railways DB's MetropolitaN, for Cologne-Hamburg services at 220 km/h. The cars were upgraded normal IC cars, but coupled among themselves permanently with special couplers, allowing wide doorless gangways. This concept was inherited by the railjet.
To confuse things even more, there are Italian State Railways FS's class E.414 locos: created from former powerheads (of the unfit first-generation ETR 500 high-speed trains, see Red Arrow to Bologna) simply by fitting them with normal couplers -- and they continue to operate in pairs by sandwiching cars... Though, sandwiching is done with normal locomotives, too.
|Two ÖBB 1016 or 1116 locos sandwich EC 113 (Frankfurt-Klagenfurt), a configuration ensuring a speedy climb while crossing the Alps.|
Photographed at the gate of castle Hohenwerfen, which you may be familiar with as the location for the crappy war movie Where Eagles Dare.
On European railways, sandwiching (as above) or multiple heading of cars by locomotives is the rule: locos aren't allowed in the middle of trains, with rare exemptions. But, as a novelty, the railjet is such a case: coupling of two trains is unrestricted. (In fact, look at the above-fold photo again.)
|My train home. A single-trainset railjet arrived with driving trailer ahead from Munich, and is about to walk up for coupling with the end of a second trainset: 1116 204, which thus will be in the middle of a train of 16 vehicles.|
So, again, why did ÖBB choose a locomotive-pulled train that is almost like a multiple unit? The reasons cited (from a presentation [pdf!] in German, edited/translated):
- inside like a multiple unit (elegant, wide and open gangways)
- technically simple
- steel carbody
- flexibility: can be extended to up to 10 cars
- use of existing locomotives
As I explained, the first has a price. The second and third mean quicker development and cheaper purchase, however, they also mean greater train weight, thus more energy for acceleration and stronger stress on the rails.
"Flexibility" can be safely considered a marketing guff: you can add cars to high-speed EMUs, too (f.e. the ETR 500 P got +1); and it would be difficult to reach top speed with even a couple of cars more. (A standard 7-car railjet with loco is 414 tons empty; the best comparison, the ICE 2 high-speed train -- powerhead + 7 cars -- is 364 t.)
Thus, in (not just) my view, what really made the difference for ÖBB was the last point.
The Universal Red Bulls
In the early nineties, with the prospect of rising line speeds and the traffic increase expected for after Austria's EU accession, the necessity of a new high-performance locomotive emerged. Siemens and its (later absorbed) local partner SGP responded by delivering three prototypes of what was the world's most advanced (and, IMHO, beautiful) locomotive well into this decade, the class 1012.
However, ÖBB refused to purchase them. The main objection being the high price; another the use of too many unique, not off-the-shelf parts (which result in expensive maintenance). So Siemens had to start over, and create a much leaner and cheaper design under ÖBB's watchful eyes.
The result: the red-painted Taurus locomotives, and a giant order for 400 of them from ÖBB (classes 1016, 1116, 1216).
|ÖBB 1116 244 and 245 (not visible) -- both of the two-system version that can cross over into Hungary and the Southern halves of the Czech Republic and Slovakia -- sandwiched EC 112 from Klagenfurt to Frankfurt. Photographed on the descent from the Tauern summit tunnel in Bad Gastein.|
Not long after I made the above photo, I was detained by police for questioning. A long back-and-forth followed, during which I was accused of walking on the tracks, which I did not and denied, showing my photos as evidence. At the end, the story I think I got was: my denouncer was some local politician, worried about suicide jump statistics... they have regional elections in March, the campaign was at full swing.
Now, the holy grail of electric locomotive development from the seventies was the universal locomotive: one equally suited for heavy and light freight, heavy and light expresses, and stopping passenger trains.
Universal locomotives became possible because locos with the then new traction electronics (asynchronous motors, inverters, electronic slip control) have no ideal load and speed regime: unlike diesels, steam or older electrics, they are almost equally (over 95%) efficient at all loads and speeds. However, the re-organisation of railways into semi-independent passenger, freight and long-distance branches from the nineties put an end to this development almost everywhere.
Except in Austria. The Tauri weren't just suited for universal operation, but ended up being used that way. The reason: that order for 400 proved too big.
|ÖBB 1016 037, one of the initial 50 single-system units, arrives with a freight train from Germany in Salzburg main station.|
With the delivery of ever more locos, ÖBB began to retire older classes en masse, then began to use Tauri even for some local trains on the flat lowlands near Vienna. In fact, an order change resulting in the more expensive 3-system class 1216 reduced their final number to 382.
I note that Siemens showcased the qualities of this latest model on a test run on Germany's latest high-speed line between Nuremburg and Ingolstadt on 2 September 2006, breaking the world record for locomotives with 357 km/h. Albeit with a single test car. (Check this page; where you'll see that the previous record holder, a French loco from 1955, was brought over from a museum for the occasion!)
So, to conclude, would ÖBB have ordered a large number of EMUs for railjet service, the Red Bulls would have ended up under-utilised. In contrast, by ordering locomotive-pulled trains, ÖBB not only kept the Tauri busy, but saved the cost of powered cars. And time.
Though, from what I heard and saw, ÖBB and Siemens rushed things a little too much to deliver on time.
Travelling by railjet
|My train waits for departure in Budapest Keleti pályaudvar [East terminal] in sleety rain.|
I travelled second-class, so my impressions correspond to that comfort level.
What I liked about the seats was their height: as someone used to the choice between headrests scaled for standard 170 cm citizens poking my shoulder blades or no headrest at all, a welcome change on second-class. However, they are steep. And on a more than 5 hour ride, one does get to feel the lack of a foot rest.
|My seat. You can make out another thing I didn't like: like boorish graffiti painters, ÖBB painted the "railjet" logo across the windows, reducing sight.|
The first thing you notice when the train starts is... a rattling noise emitted along the entire length of the cars. The culprits are the plexiglass luggage holders and the plastic panels on their underside: no damping against vibrations. This is a frequent problem on new trains; but one ÖBB would normally pay attention to.
(A colleague of mine tried out premium class. He reported that the rattling of the luxury inlays is even worse, so he switched to normal first class, which was quiet.)
The Budapest-Vienna relation is normally served by express trains of up to 14 cars pulled by Austrian Tauri (ÖBB 1116) or their Hungarian sisters (MÁV 1047). So the second thing I noticed was the greater acceleration with only seven cars. In fact, on the way back, my train got 5 minutes early on a 50 km section.
Note that constrained by line speeds, currently the trains only do 200 km/h -- just like any normal express. ÖBB promises 230 km/h for 2010. However, some scepticism is in place: that speed may require track modifications (chiefly, raising the outer rail in curves) ÖBB may not have money left for. But, maybe the in-construction Vienna-St. Pölten section will be prepared for that (in 2012).
The trains have these (airline-style, I am told) on-board info systems with GPS and LCD screens, displaying the schedule, a zoom-in map with the train's line and current location, and current (well, data-buffer-delayed) speed.
|We were racing through the station of St. Valentin at maximum speed. 'Neo-German' class designations imitate airplanes, too.|
The display is bilingual: English/German. Possibly another result of rushing things: on brochures, flyers, menus, and loudspeaker announcements, ÖBB showed ambition to use four languages - including Hungarian.
This language ambition showed even on stations. In Vienna, they apparently even employ a native speaker of Hungarian. In Salzburg, it was fun to listen to the various announcers as they struggled to recite "Budapest Keleti pályaudvar" in a phonetically near correct way (including the killer Hungarian a-s).
|Arrival in Salzburg - my train will travel on to the Bavarian capital.|
Even on second class, Facing seats have plugs for notebooks. Maybe it was the notebooks blowing a fuse that caused lights to go out three times on my way to Salzburg. Teething problem category - though, again, ÖBB normally pays attention to such things. Interestingly, the fully automatised toilets have hand-pulled doors with simple swinging door-locks - that may be cost-saving, but it may also be a wise decision to exclude a potential frequent maintenance problem.
The wide passageways are fun. Their motion is still not as restricted as on some EMUs (not to mention Jacobs bogies like on the TGV), so when traversing switches on a station, they move like a ship deck on high sea. But they enable a high-level on-seat catering service: the bistro trailers hand-pulled by the porters are HUGE.
It was interesting to listen to fellow travellers.
On the way to Vienna, an old man spoke about the train with the conductor, both Austrians. The old man praised the ride comfort, making some comparison with a car. To which the conductor replied: "I wouldn't know, I don't drive a car!" Kindred spirit, I thought.
On the way back, two old Hungarian-speaking couples sat near me. At the end, one of the old ladies summed up her opinion about comfort. She criticised the same issues about the seats I did, but also the lack of adjustability, and the shared arm rests between pairs of chairs. But, all this in comparison to business class on an airplane! So -- I was thinking laughing to myself --, with old people not having to pay the ticket price anyway, why haven't they bought a first-class seat reservation?...
As an overall impression: this train could be something - but it aint' yet.
|Trains reverse at Wien-Westbahnhof (Vienna West terminal). This is also where the two trainsets are separated again. More than enough time for a photo in afternoon sunshine.|
As a final note, the fun thing is that the locomotive-pulled railjet trains start service with a direct EMU comparison.
The ICE T are 230 km/h tilting trains. Since December 2007, a pool of 15 of the seven-car version (DB class 411) are in regular bi-hourly service between Frankfurt and Vienna, and some services on other routes. (In fact, for reasons of balance, three of them were bought by ÖBB.)
|ÖBB 4011 092 and a German sister pass Seekirchen am Wallersee. They will soon reach Salzburg, from where they'll continue separately to Bregenz resp. Munich.|
Then again, the ICE T has its problems presently, too. After the discovery of a crack in an axle last autumn, DB withdrew them all for ultrasonic tests, and then put them back into service with the tilting mechanism deactivated.
The reason for the crack is not clear yet, and the manufacturers are pointing at each other. The trains have second-generation Pendolino (see Red Arrow to Bologna again) bogies and tilting system. However, the trains built on them by Siemens and Bombardier have a maximum axleload 15% higher than the ETR 460 (for which the axles were designed for).
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