BVG Class HK
In allusion to the Großprofil series H two prototypes were built in 2000, which had the designation HK - originally, the plan had been to call them A4. Unlike their Großprofil model, cars on these trains are not fully inter-connected for passengers. Four tenders has been called, Adtranz, Bombardier Transportation, Kawasaki Heavy Industries & Nippon Sharyo and Siemens. However, Adtranz has been acquired by Bombardier Transportation in 2001 and Kawasaki Heavy Industries has only been keen in the C751B contract, therefore Bombardier Transportation has been selected as the preferred bid.
| BVG Class HK | |
|---|---|
 A HK-type train | |
| In service | 2001-present |
| Manufacturer | ADtranz ,Bombardier Transportation |
| Built at | Hennigsdorf |
| Constructed | 1999-2006 |
| Entered service | 2001 |
| Number built | 24 trains |
| Formation | 4 per train set DT–M–M–DT |
| Fleet numbers | 1001 - 1024 |
| Capacity | 296 seated; 1,624 standing; 2 PIW spaces |
| Operator(s) | Berliner Verkehrsbetriebe |
| Line(s) served | U1 & U2 |
| Specifications | |
| Car body construction | Aluminium-alloy double-skinned construction |
| Car length | 9.874 m (32.40 ft) |
| Width | 2.65 m (8.7 ft) |
| Height | 1.80 m |
| Doors | 1.80 m, 8 per car |
| Maximum speed | 80 km/h (50 mph) |
| Weight | 226.8t /335.9 t (laden) |
| Power output | 2.24 MW (3,000 hp) |
| Transmission | WN Drive |
| Acceleration | 1.0 m/s2 |
| Deceleration | 1.2 m/s2 (service) 1.3 m/s2 (emergency) |
| Auxiliaries | IGBT–VVVF Auxiliary Inverter with Battery Charger 80 kVA–16 kW |
| Electric system(s) | 750 V DC |
| Current collection method | Third rail |
| Braking system(s) | Regenerative Braking, Resistor Braking, Air Brakes |
| Track gauge | 1,435 mm (4 ft 8 1⁄2 in) standard gauge |
A full train can be divided into two half trains. The production of the first train started in May 2005. On the U2 these new trains now represent a majority of trains run. They replaced all the A3L67 trains in 2007.
Majority of the trains run on the U2, while some of them ran on the U1 if there is an emergency situation like trackworks or pullover and hardly any ran on the U3 and U4.