Hamburg U-Bahn Type DT3

The Type DT3 is a three-car electric multiple unit (EMU) train type operated by the Hamburger Hochbahn AG on the Hamburg U-Bahn.They were first introduced in 1968 to replace the 1911 to 1929-built Type T cars and to speed up the journey times on line U1.^{[citation needed]}

HHA-Baureihe DT3
A DT3-LZB train at Landungsbrücken station in April 2009
In service	1968 – present
Manufacturer	LHB, BBC, Kiepe
Constructed	1966 (prototype)[citation needed] 1968–1971
Entered service	1968-2023
Refurbished	1994–2001, 2016
Scrapped	1999–2003, 2017, 2021, 2024
Number built	128 units
Number in service	0 units
Number preserved	2 units
Number scrapped	115 units[citation needed]
Fleet numbers	originally: 9603–9983 later: 801–926, 931, 932
Capacity	364 (92 seated) (DT3)[1] 90 seated (DT3-LZB)
Operators	Hamburger Hochbahn AG
Depots	Farmsen, Barmbek
Specifications
Train length	39.52 m (129 ft 8 in)[1]
Width	2.48 m (8 ft 2 in)[1]
Height	3.35 m (11 ft 0 in)[1]
Doors	2 pairs per side (per car)
Maximum speed	80 km/h (50 mph)
Weight	47.1 t (46.4 long tons; 51.9 short tons)[1]
Power output	640 kW (860 hp)[1]
Acceleration	1.2 m/s²[1]
Deceleration	1.2 m/s² (emergency)[2]
Electric system(s)	750 V DC third rail
Current collector(s)	Contact shoe
UIC classification	Bo'Bo'Bo'Bo'
Braking system(s)	Dynamic main brakes, Westinghouse air brakes
Safety system(s)	Sifa LZB (sets 921–926)
Coupling system	Scharfenberg
Track gauge	1,435 mm (4 ft 8+1⁄2 in)

Variants

• DT3: non-refurbished sets, all withdrawn^[3]
• DT3-LZB: sets 921 to 926 fitted with Linienzugbeeinflussung (LZB) in 1980/1981^[3]
• DT3-E: trains refurbished from 1995 to 2000 with new polyester cabs^[3]
• DT3-N^{[citation needed]}: ten refurbished sets used as spare cars^[4]

• 
  DT3-E with new polyester cab

Interior

The trains have a 2+1 seating arrangement. Refurbished trains are equipped with a passenger information system since 2000.^[3]

• 
  Interior of a refurbished DT3-E train

Technical specifications

The trains are built to an articulated design, and are formed as three-car units. The end cars are based on the Type DT2, with a 10.72 m (35 ft 2 in) long intermediate car in-between.^[3] They are equipped with high voltage cam switches, quill drive, and a microprocessor-controlled wheel slide protection system.^[3]

• 
  Driver's cab of a DT3
• 
  Side shot of a DT3 at Hauptbahnhof Nord station

DT3-LZB

Six sets were fitted with Linienzugbeeinflussung (LZB) in 1980 and 1981 and were used for driverless operation trials on the branch to Großhansdorf station. The automatic operation was observed by a conductor permanently sitting in the cab, they also had to dispatch the train in stations.^{[citation needed]} The experimental operation ended in 1985, since then the units were in normal operation.^[3] During the refurbishment of many DT3 units in the 1990s, the DT3-LZB only received the interior and car body refurbishment and did not get their front replaced.^[3]

The LZB trains all were retired on 9 December 2016 and scrapped in April 2017.^{[citation needed]}

History

The trains were built between 1968 and 1971.^[3] 18 units were scrapped in 2017.^[5]

Refurbishment

Many of the units were rebuilt between 1995 and 2000 and received a newly designed polyester front ends, a new interior design, and windows between the cars and between the driver's cab and passenger compartment.^[3] The rebuilding became necessary due to structural issues with rust on load-bearing parts of the car bodies.^[3] The rebuilt units are designated as DT3-E.^[3] A total of 62 units were refurbished as of August 2005,^{[3][needs update]} the rest of the units were replaced by new DT4 units, retired and scrapped between 1996 and 2003.

In June 2015, the operator Hamburger Hochbahn announced another refurbishment for ten DT3-E units to extend their lifespan for ten more years.^[6] This refurbishment will include the replacement of the old control equipment, the fitting of door closing alarms, as well as the renewal of the interior and car bodies.^[7] The improvement was going to make the refurbished cars incompatible to the other DT3-E, thus they will be designated as "DT3-N" to distinguish them from non-refurbished cars.^{[citation needed]}