Port Authority of Allegheny County operates 55 cars on an 22.5 mile system

Car Specifics 
Manufacturer/Model:  Siemens SD 400 
Vehicle type: Double ended Articulated
Developed by: 
Date in service: 
Number of cars ordered: 55
Number of cars still in service (to date): Unknown
Number of trucks: 3
Number of axles: 6

Car Body
Manufacturer: Siemens Transportation Systems
Underframe: Low Alloy High Tensile Steel
Superstructure: Low Alloy High Tensile Steel
Interior Finish: 
Floor: Rubber over Plywood
Steps:
Doors: Three High Level Doors and One Low Level Door per Side
Windows:
Seats: 62
Disabled Access: High Level Platforms / High Level Doors

Suspension, Propulsion, Braking
Trucks/Bogies:
Suspension:  Rubber Chevron Springs (Primary), Air Spring System (Secondary)
Truck centers:
Wheels: 
Wheel base:
Track gauge: 62.5" (1,588 mm)
Motors: Dual DC-Chopper, Monomotor Two Motors per Car
Gear ratio: .
Gearbox: . 
Slip/slide protection:
Service Brakes: Pneumatic Friction Brakes
Track Brakes:
Air compressor:
Traction Motor Rating: 205 kW (275 hp) (one hour rating, each motor)

Vehicle Capacity
Seated Load:  62
Design Load:
Crush Load:

Passenger Comfort
Heating: Baseboard
Air-conditioning: Compressor under car, condenser on top of car

Vehicle Dimensions
Length over couplers:  84 feet, 8 inches  (25.81m)
Length over body ends:
Width:  8 feet,  9.6 inches  (2.65m)
Height (rail to roof):
Height (rail to floor):
Pantograph operating range:
Empty weight per car:  85,800 lbs.  (39,000 Kg)
Interior headroom: 6 feet, 9 inches 
Interior width (articulated section):
Doorway width (minimum):
Doorway height:
Step height: None (High Level Platforms / High Level Doors)

Vehicle Performance
Maximum design speed: 50 mph
Maximum operating speed:
Maximum grade:
Service acceleration on level tangent track: 3.0 mphps
Service braking on level tangent track: 3.7 mphps
Emergency braking on level tangent track:
Minimum horizontal curve radius:
Minimum vertical curve radius:

Electrical and Control Systems
Power Supply: 650 Volts DC
Low voltage power supply:  16.5 volts
Interior Lights
Motor Control:
Amperage draw:

See the Siemens page for more information.

  Updated May 26, 2000