HHA Class DT4

HHA-Baureihe DT4
DT4.6 in Jungfernstieg station
Manufacturer	LHB, ABB
Constructed	1988-1991 (DT4.1) 1993-1995 (DT4.2) 1996-2000 (DT4.3 & DT4.4) 2002-2005 (DT4.5 & DT4.6)
Number built	126 sets
Capacity	182 seats, 223 standing
Operator	Hamburger Hochbahn AG
Specifications
Train length	60.28 m (197 ft 9 in)
Width	2.58 m (8 ft 6 in)
Height	3.58 m (11 ft 9 in)
Maximum speed	80 km/h (50 mph)
Weight	76.9 t (75.7 long tons; 84.8 short tons)
Power output	1,000 kW (1,340 hp)
Electric system(s)	750 V DC
UIC classification	Bo′2′Bo′+Bo′2′Bo′
Braking system(s)	Dynamic main brakes, automatic air brakes which completely stops the train
Safety system(s)	Sifa
Gauge	1,435 mm (4 ft 8 1⁄2 in)

The HHA Class DT4 is a four-car electric multiple unit train built for the Hamburg Hochbahn. It was first introduced in 1988 and is currently the newest type of metro trains in Hamburg. They were introduced to replace the whole DT1 fleet, most of the DT2 trains and some DT3 trains and to service line extensions to Mümmelmannsberg (1990), Niendorf Nord (1991) and Norderstedt Mitte (1996).

Today, the DT4 fleet have information screens in the interior, door opening buttons (DT4.1 and 4.2 formerly had door handles to open the doors), anti-vandalism seats and surveillance cameras. The DT4 fleet is mostly running on the U1 and U2 line. In peak hours, they are running on circle line (U3) as well.