User Guide

MICROSOFT TRAIN SIMULATOR ENGINEER’S HANDBOOK
HOW TO DRIVE AN ELECTRIC LOCOMOTIVE | 59
AMTRAK ACELA EXPRESS
The Amtrak
®
Acela
SM
(pronounced “ah-CELL-ah”) Express is a new high-speed electric train built
for Amtrak by the companies that manufacture the Learjet (Bombardier) and the French TGV train
(ALSTOM). Each Acela Express trainset consists of five passenger cars (one First class and four
Business class), a café car, and two 6,000 hp Power Cars (locomotives), one at each end. Each
Power Car has a pantograph that draws down power from the overhead electrical lines (the catenary).
The trainset is semi-permanently coupled, and there is effectively no slack between the cars. The
Acela Express trainset uses a state-of-the-art “tilt” system that allows the train to take curves at top
speeds of up to 165 mph (265 km/h) on the test track.
The Acela Express uses computer technology in almost every system on the train. Digital displays in
the cab show the train’s status and operational data such as speed, braking, and tractive effort. The
Automatic Train Control (ATC) system ensures that the train obeys signals and speed limits. If the
engineer fails to observe speed limits or to slow the train to the appropriate speed upon receiving
an approach or stop signal, the ATC system slows the train automatically. If the engineer fails to
acknowledge this change within five seconds, full brakes are applied (this is called a “penalty brake”
application). An Alerter system also sounds an alarm if the train’s controls are not operated during
a 25-second period. The engineer must respond to this alarm within 15 seconds or the brakes will
be applied and the power will be shut down, bringing the train to a halt.
The Acela Express uses several different types of brakes. The dynamic brakes can dissipate braking
energy electrically either by regeneration by returning the energy to the catenary or rheostatically by
converting the energy to heat. Electronically controlled pneumatic brakes with an air backup provide
the primary air brake system. Disc brakes provide the majority of pneumatic braking, while tread
brakes provide supplemental braking and also keep the wheels clean for maximum adhesion between
the wheel and the rail. The Brake Control Computer blends the dynamic and air braking systems to
provide smooth, efficient braking with minimal wear-and-tear on the components.