While running some errands earlier today I had a brief stopover in order to try and capture something only recently introduced on the rails around Frankfurt ...

Suburban EMU 420 429 working the S8 peak hour service 8819 from Kelsterbach to Frankfurt Central Station together with 420 430 and calling at Niederrad.

Well - these trains are not really "new" in a technical sense - the class having been built from 1969 till 1997. However, they are a novelty in that they belong to the 7th batch which has never been permanently allocated to the Frankfurt depot before. The 7th and 8th batch units have a number of differences compared to the previous six batches - such as plug doors instead of sliding doors, redesigned interior, double number of brake disks, spring-loaded parking brakes and a Railvox passenger information system. In recent years the 7th and 8th batch sets were refitted with LED matrix destination indicators in place of the original rollsigns, which can be seen here. Also, two 7th batch units - 420 400 and 416 - were rebuilt to what was designated the "420 Plus", including an even more extensive passenger information suite as well as air conditioning units and a newly redesigned interior. These demonstrators were subsequently tested in everyday traffic and proposed as an alternative to procuring new EMUs for the next tender for the Stuttgart suburban network. However, the 420 Plus project was not pursued any further when the Stuttgart Transport Association (Verkehrs- und Tarifverbund Stuttgart, VVS) did demand newly built units. The remaining 7th and 8th batch units will remain in service on the Stuttgart network until 2013.

In any case - four 7th batch units from Stuttgart (420 425, 428, 429 and 430) were reallocated to the Frankfurt depot in the second half of 2009, but required a rather extensive overhaul before they could be put back into traffic. That overhaul appears to have been completed only a few weeks ago, allowing the "new" 420s to finally enter service. They are mainly used for peak hour services as well as late evening and Sunday morning short workings on lines S8 and S9.