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21 Table 2-7. Questionnaire view of the extent and seriousness of problems. System Portland Boston Newark Santa Clara Houston San Diego Derailments No Yes Yes No No Too early Excessive wheel wear No Yes Yes No No to say Excessive track wear No Yes Yes No No Excessive trackside noise No Neutral No Yes Neutral Excessive interior noise No Yes No No Yes Excessive poor riding No Neutral No No No Mitigation introduced Yes Yes Yes No Yes Mitigation successful Yes Partly Partly N.A. Partly No significant differences were seen. This is discussed more 2.6 Trends in Chapter 3. The U.S. systems studied are not proposing to replace their LFLRVs with high-floor cars and will probably expand the use 2.5 European Experience with of LFLRVs. Sometimes this will be in situations where they This Type of Vehicle have not been used before (e.g., a planned street running exten- As indicated in Table 2-1, numerous LFLRVs with a center sion of the Newark Subway). Other cities will introduce them, truck of this type and IRWs operate in Europe. The experi- although the possibility of introducing other configurations of ence of the European team members working on this research partial low-floor vehicle or 100-percent low-floor vehicles may project was that, although similar issues had emerged in eliminate the need to do this. Europe, such issues tended to be less serious and were now Given that older systems may have more difficulty intro- being effectively managed. ducing these cars than systems that can be designed to accom- One German system that has been using a relatively large modate them, it is interesting to consider what other cities fleet of cars of this type for 10 years has had the following with "traditional streetcar" systems are planning. experience: In June 2005, the Toronto Transit Commission initiated a procurement process for low-floor vehicles to replace There was more wear on IRWs than other wheels. 96 existing streetcars. Four issues may make this process Trailer truck wheel wear was roughly the same as motor difficult: truck wear, whereas it would normally be expected that wheels on motor trucks wear faster. The use of single-point track switches that may cause issues Noise levels had been expected to reduce with IRWs for IRWs, because of their improved curving performance, but the Curve radii of 36 feet (inside rail), noise levels remained the same. Low axle load requirements, and Performance issues were found to be worse on badly Prolonged 8-percent and some 7.5-percent grades that aligned or maintained track sections. favor vehicles with all axles powered (8). Re-profiling of wheels tends to be in the range 10,000 to The Southeastern Pennsylvania Transportation Authority 40,000 miles, but IRWs typically are at the lower end of this (SEPTA) started a procurement for LFLRVs in 1998, but the range. process was cancelled because of the significant costs. The Small-diameter wheels have been used as an alternative to cost-driving factors included IRWs, but these have their own issues, so it is an issue of bal- ancing the overall performance of these options in the specific Curve radii of 35.5 feet; application. Non-standard (5 feet 21/4 inch) gauge, which means that Derailments occurred on another system where 10-percent vehicles have to be designed specially; low-floor cars are being used. These vehicles have IRWs but Clearance requirements limiting the length and width of combine these with a more complicated body configuration, cars; and allowing more degrees of freedom. There has been a tendency The small size of the order (12 vehicles). to revert to partial low-floor vehicle solutions to avoid the increased wear and other issues associated with 100-percent SEPTA plans to replace 141 cars eventually and will re-eval- low-floor cars of this type. uate the use of LFLRVs then (9).

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22 Another trend is the increase in sales of "standardized" similar to vehicles operating in Cologne (Germany), designs, permitting comparison of almost identical models Alphen an der Rijn (Netherlands), Stockholm (Sweden), on different systems worldwide. Istanbul (Turkey), and Croydon (UK). The Houston/San Global standardization has only a limited relevance to Diego Siemens "Avanto S70" design, also now on order for the U.S. and Canadian market because of the different stan- the Charlotte Area Transit System, has also been ordered by dards that apply compared with the European light rail Paris RATP--although this latter order has not entered market, which is much larger. Despite this, two products in service yet. This is suitable for the U.S. and Canadian mar- use in the United States and Canada may be directly com- ket because the European design was intended for shared parable with experience elsewhere. The Minneapolis vehi- operation of LRVs on heavy rail routes and, therefore, cle belongs to the Bombardier Flexity Swift family and is meets U.S. buff load requirements.