class 146.0 locomotives. Line S 2 The Flughafen-S-Bahn ("Airport S-Bahn") connects Pirna, Heidenau and Dresden with Dresden Airport and the microelectronics companies located in the north of the city. Between Dresden-Neustadt and Pirna/Heidenau (on working days) or Dresden Hbf (on weekends and holidays) S 2 services run along the same route as the S 1 services, so that there are services at intervals alternating between 10 and 20 minutes on this section. The sets of the S 2 are made of two double-deck carriages which, unlike the ones on the S 1 and S 3 services, are equipped with an emergency brake bypass to avoid being stopped in the tunnel to the airport station. A railway line between Dresden-Klotzsche and the airport was rebuilt and extended to connect to the airport. Already before the opening of the S 2 on 22 May 1998 a Regionalbahn service operated to Dresden Grenzstraße and served to connect with EADS EFW and ZMDI. The S 2 branches off the Görlitz–Dresden railway just north of Klotzsche station. Trains running towards the airport pass over the non-electrified line towards Görlitz. The Dresden-Klotzsche–Dresden Airport railway runs as a single track and ends at a double-track underground station under the terminal of Dresden Airport. The construction of the new and upgraded line began In the middle of 1998. The beginning of operations to the airport coincided with the commissioning of the new airport terminal, on 25 March 2001 with 36 diesel multiple units services operating daily at half-hour intervals. In the first five months of operations, the average utilisation rate was maintained at 32%, with a total of 1,400 passengers per day. Around 810,000 passengers were counted on the line by the end of 2001. The electrification of the sections between Dresden-Neustadt and the airport began at the beginning of March 2002. In 2002, 683,000 travelers were counted on the line. By the end of 2004, the operations consisted of a total of eight newly procured double-deck vehicles. These include, among other things, air conditioning, a barrier-free toilet and electric sockets in first class. The line was extended to Pirna at the timetable change in December 2004. Some of the 1st class seats were redesignated as 2nd class seats. From 9 December 2007, services of the S 2 were generally operated with three double-deck carriages due to the increased demand. From 2009 onwards, two or three carriages were