2017. These will replace the present A3L71 series. Großprofil Today, only trains of the F and H types are in active service. When the city of Berlin planned the new Nord-Süd-Bahn, it ordered two cars in the Großprofil with a much greater width of from the Linke-Hoffmann factory in Breslau. They were delivered in 1914 and put through trials by the Siemens company. The new cars with their bigger passenger capacity of 111 seats were intended to save money on the construction of platforms, because fewer cars were required to carry the passengers. This created a problem with platform access, which could only be solved in the 1950s and 1990s through enlargement of the platforms. For the U-Bahn of the AEG company, today's U8, two prototypes were ordered from the Cologne train factory van der Zypen & Charlier. They were built in 1916, but were never put into service. The Berlin train authority used the two trains from 1921 on, on a suburb route. B type cars Only after the 1920s German inflation was over Großprofil cars could finally be ordered. In 1924, the first 16 multiple units and 8 normal passenger cars were delivered. Because they had big elliptical front windows, they were commonly called Tunneleulen ("tunnel owls"). The cars were 13.15 meters long and had 3 double sliding doors. This series was called BI. From 1927 to 1928, 20 further multiple units and 30 passenger cars were delivered to the Nord-Süd-Bahn AG. Because they had an improved propulsion system, they got the designation BII. They were all deployed to Line 6 and 8, before it was further redeployed in 1966 to Line 6. The last BI and BII trains were retired in the summer of 1969. C type cars As early as 1926, the first CI trains were trialed. They were 18 meters long and were tested thoroughly, before production started with the CII and CIII types. On the outside, CII and CIII trains were identical, but they were very different on the inside. The electricity driving the train was routed directly through the steering in the CII ("Schaltwerksteuerung"), while the CIII used the safer "Schützensteuerung" (with only a weak control current running through the controls). In 1930 the first CIV cars were delivered. For the first time, aluminum was used as a construction material. This way, weight could be reduced by 12%. Especially these CIV cars, but