Product Features and Details
The conversion programmes for 3yg- and 4yg coaches allowed the Germanï¿½Federal Railway to address the shortage of coaches caused by the war forï¿½the first time from the mid-1950s. However, the construction programmesï¿½were limited initially to developing urban rapid transit and express trainï¿½coaches. Following this, the German Federal Railway created capacity forï¿½developing new commuter coaches (n-coaches).ï¿½
The constantly growing demand for increased traffic volume and the factï¿½that the 3yg had only been designed for a short service life, led to theï¿½appearance of the first prototypes for the new n-coaches in 1958. Basedï¿½on the findings of the preceding new developments and prototypes, threeï¿½basic types emerged with five 1st class compartments in the centre of theï¿½coach and two large 2nd class cabins (AB4nb), three large 2nd class cabinsï¿½(B4nb) and two large 2nd class cabins and baggage compartment withï¿½space for the train conductor (BD4nf). Although prototypes had also been trialledï¿½with side panels made from aluminium, standard steel and corrugated sideï¿½walls, metal panelling made from stainless steel (V2A) was eventually chosenï¿½for mass production. Since the coach paintwork corrosion protection was notï¿½required for this material, the n-coaches were abraded under the windowsï¿½using a peacock eye pattern. This abrading pattern and the silver surface of theï¿½V2A quickly earned the n coach the distinctive nickname 'Silberlinge'.ï¿½
Except for a few models fitted with lightweight design Minden-Deutz bogies,ï¿½the n-coaches were fitted with block brakes (MD42), which were replaced withï¿½disk brakes (MD43) in later series. In order to change passengers as quickly asï¿½possible, the otherwise common end entrances were abandoned and positionedï¿½approximately a third of the way along the coach as double entrancesï¿½with hinged-folding doors. The basic design of the n-coach proved so successfulï¿½that between 1960 and 1980 a total of about 5000 coaches were constructed by different coach manufacturers as well as at the Karlsruhe and Hannoverï¿½refurbishment facilities (Aw). At first, conditions in the extremely crampedï¿½conductor's space in the BD4nf were less than ideal, and it was soon nicknamedï¿½the 'rabbit hutch' by staff, leading to discontent and safety concerns.ï¿½As a result, Aw Karlsruhe rebuilt the conductor's cab, producing aï¿½control car in 1972 with a fully-fledged conductor's cab without anyï¿½through access to the next coach. These changes meant that the Karlsruheï¿½version differed significantly from the previous 'rabbit hutch' with itsï¿½passageway between the coaches.ï¿½From the mid-1980s, the Federal Railways started to modernise coachesï¿½that were in some cases already 20 years old. Following several designï¿½studies, the positive features of the individual programmes were combinedï¿½at Aw Hannover in the new Hannover design. New features also consistedï¿½of the mint green paintwork or new sliding windows with plastic frames. Thisï¿½design, which was also installed by PFA Weiden or OFV Verona using alternativeï¿½interior colours, can still be found in modern n-coaches that have beenï¿½painted in the DB AG corporate colours.
Other conversions were performed on the control cars. The two designs that hadï¿½been introduced earlier were only suitable for either diesel or electric traction,ï¿½depending on the control panel installed. For this reason, a new conductor's cabï¿½was designed at Aw Wittenberge, based on the DB standard driver's cab of theï¿½BR 111, so that the control cabs could be deployed with greater freedom.ï¿½Numerous 'rabbit hutches' and also Karlsruhe versions were subsequentlyï¿½converted to the Wittenberge model. In order to meet the demand for push-pullï¿½trains, DB AG also included standard 2nd class coaches in the conversion programme.