The N/W STRG DISC memo appears when the tow control lever is set to bypass the nosewheel steering. At what point does the memo change color from green to amber?

The N/W STRG DISC memo appears when the tow control lever is set to bypass the nosewheel steering. At what point does the memo change color from green to amber?

• A. Before engine start
• B. While taxiing
• C. Immediately after the first engine starts
• D. After the start of the first engine

Answer: (D)

The message is a status cue tied to nose wheel steering when the tow control lever is set to bypass. When this bypass is selected, the nose wheel steering path is intentionally made unavailable for normal cockpit control, and the N/W STRG DISC memo appears to remind the crew of this condition. The color coding signals how the system is powered and what action is required. Green indicates a non-critical, informational state. After the first engine starts, hydraulic power to the steering system comes online and the bypass condition is effectively in effect for taxi, so the indicator shifts to amber as a caution to the crew that normal nose wheel steering is not available and to proceed with care (e.g., towing or ground handling with the bypass engaged). That transition timing—after the start of the first engine—is why the correct answer is that the color changes once the first engine has started.

The message is a status cue tied to nose wheel steering when the tow control lever is set to bypass. When this bypass is selected, the nose wheel steering path is intentionally made unavailable for normal cockpit control, and the N/W STRG DISC memo appears to remind the crew of this condition. The color coding signals how the system is powered and what action is required. Green indicates a non-critical, informational state. After the first engine starts, hydraulic power to the steering system comes online and the bypass condition is effectively in effect for taxi, so the indicator shifts to amber as a caution to the crew that normal nose wheel steering is not available and to proceed with care (e.g., towing or ground handling with the bypass engaged). That transition timing—after the start of the first engine—is why the correct answer is that the color changes once the first engine has started.