Which term specifies a speed not exceeding 15 mph, except in ASC territory, with the cab signal indicator governing up to 30 mph?

• A. Limited Speed
• B. Maximum Authorized Speed (MAS)
• C. Slow Speed
• D. Restricted Speed

Answer: (D)

Restricted speed is the slow, cautious operating speed category where you must be able to stop within the range of vision and proceed with due regard to conditions. Normally this limit is 15 mph. In ASC territory, the cab signal indicator governs up to 30 mph, so you may ride up to 30 mph only if the cab signal shows that speed. That combination—15 mph baseline with an ASC-enabled 30 mph allowance indicated by the cab signal—matches the described rule. The other terms refer to different speed concepts: Limited Speed, Slow Speed, or Maximum Authorized Speed describe other contexts or general track limits without this specific 15 mph baseline plus ASC exception.