Combino

The Combino is a low-floor tram produced by Siemens Transportation Systems (formerly DUEWAG). The first prototype was produced in 1996 at the Duewag works in Düsseldorf; the trams are now made in Krefeld-Uerdingen.

Due to its modular design using standardised components, and the resulting reduced costs, the Combino was for a time one of the most successful tram types. They were sold to twelve jurisdictions and a further development was sold to two others.

In 2007, a new generation of Combinos was sold to Bern and was known as the Combino XL. This was an updated version of the original design and was intended to correct defects in the original design.

Subsequently, the model was again renamed and is now known as the Avenio M. Fourteen of these were produced in 2011 with 12 going to Erfurt and two to Nordhausen.

The Siemens line has been complemented by a new design of trams called the Avenio, which have been built on the design technology of Combino Plus in Sul de Tejo and Budapest. Unlike the Combino, it does not have suspended sections but rather two axles under each body section. In essence, it is like a train of two axle cars. As of 2014, the Avenio is on order for The Hague and Munich.

Use of the Combino world-wide

Around 500 trams went into service in the following cities:

Control panel of Poznań Combino

Locality	Operator	Type	Model Year	Number
Netherlands Amsterdam	Gemeentevervoerbedrijf (GVB)		2005	155
Germany Augsburg	Stadtwerke Augsburg Verkehrsgesellschaft mbH (StwA)		2004	41
Switzerland Basel	Basler Verkehrsbetriebe BVB		2002	28
Switzerland Bern	Bernmobil (ehemalige Städtische Verkehrsbetriebe Bern)		2003+2009/2010	15+21
Germany Düsseldorf	Rheinbahn AG	NF 10	2000-2002	36
		NF 8	2003-2004	15
		NF8U	2006-2007	15
Germany Erfurt	Erfurter Verkehrsbetriebe AG		2000-2006	48
Germany Freiburg im Breisgau	Freiburger Verkehrs AG (VAG)		2003	18
Japan Hiroshima	Hiroshima Dentetsu		2002	12
Australia Melbourne	Yarra Trams	D1	2002-2004	38^[1]
Australia Melbourne	Yarra Trams	D2	2003	21^[2]
Germany Nordhausen	Stadtwerke Nordhausen Verkehrs- und Stadtreinigungsbetrieb GmbH		2002	7
Germany Nordhausen		Combino Duo	2004	3
Poland Poznań	Miejskie Przedsiębiorstwo Komunikacyjne w Poznaniu Sp. z o.o.		2004	14
Germany Potsdam	Verkehrsbetrieb Potsdam GmbH (ViP)		1998-2001	16
Germany Ulm	SWU Verkehr GmbH		2003-2008	10

Twenty-two trams were ordered by Verona, Italy, but the contract was cancelled because of the technical problems noted in this article.

Technical specifications

Bogie

The tram is largely made out of aluminium, with a welded underframe to which the body framework is bolted in sections, which means that the Combino can easily be adopted to different lengths, widths and gauges. The length of the trams varies from 19 metres (62 ft) (Nordhausen "Duo" and Melbourne D1) to a world record 54 metres (177 ft) (Budapest), accommodating between 100 and 250 passengers. All versions are designed to have a 300-millimetre (11.8 in) floor height and a 10-tonne (11-short-ton) axle load. It can be built as a one-way or a two-way vehicle, and it is also produced as DuoCombino with an additional diesel propulsion system, courtesy of BMW's M67 3.9-litre twin-turbocharged V8 engine. The only city to receive the DuoCombino was Nordhausen, Germany.

They usually take 600V DC overhead power and convert this to 400V 3-phase AC power for the regenerative low wear motors via 3 IGBT PWM inverters. On board controls, lighting and air conditioning run at 24V DC.

2004 recall due to flaws in construction

On March 12, 2004, Siemens admitted to problems concerning the stability of the car bodies and, as a precautionary measure, instructed all public transportation services to take all Combinos with a service distance of more than 120,000 kilometres (74,565 mi) out of service.^[3] Torsion forces generated in S-curves were much higher than anticipated, leading to cracks around the articulations between the car modules. Subsequently, hairline cracks were found in the joints of the aluminium bodies, which could cause the roof to collapse in the case of an accident.

Interior

The problem was acute in Combino cars that had run more 150,000 km. Cracks were reported on the connections between the sidewalls and the roof girders such that the safety of passengers in the wheel-less modules could not be assured in the event of a severe collision. These flaws were reported in many cities that had adopted the Siemens-Combinos, such as Düsseldorf, Freiburg, Augsburg, Erfurt, Hiroshima, Nordhausen, Basel, Potsdam, Bern, Amsterdam and Melbourne. In March 2004 Siemens Transport Systems confirmed that body-shell problems were emerging at high mileages and it advised all operators to take out about 400 Combinos that had run more than 120,000 km.^[3]

Siemens launched a three-stage process of rebuilding the 454 modules affected. Under this process the Combino modules were reinforced to give an expected 30-year life.^[4]

Potsdam

In 1997, the public transportation authorities of the city of Potsdam were the first to purchase Combino cars. The advantages of its low-floor technology were stressed during the introduction. A total of 48 cars were to be bought through 2009.

The order from Potsdam was of great importance for advertising the Combino in other cities. Cars from Potsdam were frequently used for demonstrations.

After a short period of service, many inhabitants of Potsdam noticed noises during the operation of the cars louder than those of the previously used Tatra cars. In March 2004, the 16 Potsdam cars were taken out of service. As a replacement, several Tatra cars which had been given to museums were taken back into service. The shortage was aggravated by the fact that several old cars had been sold to Hungary just a month before.

In June 2004, Potsdam and Siemens "amicably" declared that the at the time 32 outstanding cars were not going to be delivered. This decision is likely to have consequences for other cities.

Amsterdam

Two Combinos in Amsterdam

In June 2004, the first Amsterdam Combinos passed the mileage threshold of 120,000 km and were taken out of service. Earlier, Siemens technicians had identified stress fractures in the door segments of two of Amsterdam's oldest cars. But, according to Siemens, those turned out not to be dangerous, which is why the cars continued to be used. At the end of April 2004, it was decided not to call upon the twelve undelivered cars which were outstanding at that time.

Siemens is experimenting with a new model in Amsterdam, the Combino Supra (Combino 2091). In September, it turned out that 32 of the 48 oldest Combinos had cracks in the floor segments. Siemens is expected to patch up these trams temporarily. A structural solution for the construction flaw was announced for September 2004. Beginning in 2005, a two-year program was to be started to fix the cars. All Amsterdam cars were to be brought to the plant in Germany where their hulls were to be strengthened.

Poznań

Poznań announced in 2002 a tender for low-floor trams. Siemens won the contract with Combino. Poznań ordered 14 trams, each consisting of five modules, three double doors and three bogies, identical to the Amsterdam version. The first Combino entered service at the end of 2003. Due to flaws in construction, not all trams were in active service. An agreement between Poznań and Siemens AG provided that the city would pay the fraction (31%) of trams' cost only after the refit of all 14 Combinos. Combinos are usually used on the Poznański Szybki Tramwaj (Poznań Fast Tram) (light rail), that is on lines 14, 15 and 16. On weekends they also turn up on line 6. On match days instead of 6 and 15 whose route is close to stadium combino turn up at route 5.

Combino Supra

Combino Supra Budapest NF12B with a legendary Ganz UV in Budapest

The current Combino model (Combino MkI) will no longer be produced. For the cities which have already ordered Combinos, such as Budapest (Hungary) and Almada (Portugal), Siemens will provide trams based on an older ADtranz design , under the new name Combino Supra. The new Combinos will have thin stainless steel rather than aluminium carbodies. Siemens now also wants to sell the Viennese Ultra Low Floor (ULF), another 100%-low-floor model, to other cities. The first two Combino Supras were delivered March 14, 2006 to Budapest.

After serious initial teething problems, which involved door mechanism malfunctions that led to a recall of all Budapest Combino trams by Siemens, the trams were in regular service during 2006. After they had been repaired, Budapest's government decided that they would return them to Siemens. However, this did not happen because of contractual terms. The local public transport company began using them in 2007 and now they are working successfully again.