Locomotive Operation and Control Flashcards
7 cards from real LEC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Locomotive Operation and Control flashcards as text
Which factor most significantly affects the stopping distance of a freight train compared to a passenger train of the same length?
Answer: The higher gross weight of freight cars increases kinetic energy and lengthens stopping distance
Greater gross weight means significantly more kinetic energy that the braking system must absorb, resulting in much longer stopping distances for loaded freight trains.
When operating in a cab signal territory, the on-board signal display changes from 'Clear' to 'Approach.' The engineer must:
Answer: Immediately reduce speed to the approach speed indicated before passing the next signal
Cab signals require the engineer to achieve and maintain the speed associated with the displayed aspect before reaching the next signal location.
What is the effect of operating a locomotive with a 'cut-out' (isolated) traction motor on available tractive effort?
Answer: Available tractive effort is reduced proportionally to the number of motors isolated
Each isolated traction motor directly reduces the locomotive's total tractive effort output, and the engineer must account for this reduced capacity when planning train handling.
A locomotive engineer is required to sound the horn for a public grade crossing. The standard horn sequence is:
Answer: Two long, one short, one long blast, beginning at least 1/4 mile before the crossing
The standard FRA horn sequence for public grade crossings is two long, one short, and one long blast, started no less than 1/4 mile before the crossing.
During a running brake test, the engineer applies a 6-8 psi service reduction and the train shows no retardation. The most likely cause is:
Answer: One or more cut-out cocks are closed, preventing air from reaching car brakes
If brake cylinder pressure cannot build due to closed cut-out cocks or a systemic failure, cars will not respond to service applications, resulting in no felt retardation.
When a locomotive is equipped with Electronically Controlled Pneumatic (ECP) brakes, what is the primary operational advantage over conventional pneumatic brakes?
Answer: Simultaneous brake application throughout the train, dramatically reducing in-train forces and stopping distance
ECP brakes apply simultaneously to all cars via electronic signals rather than relying on a pressure wave that travels from front to rear, greatly reducing stopping distance and in-train slack forces.
Under FRA Hours of Service regulations, a freight train crew member who has been on duty for 11 hours and 30 minutes must:
Answer: Be relieved within 30 minutes before reaching the 12-hour limit
FRA regulations prohibit railroad employees from requiring or allowing covered service employees to remain on duty beyond 12 consecutive hours; relief must be arranged before the limit is reached.