What does the casualty code NVRG indicate?

What does the casualty code NVRG indicate?

• A. Unusual noise or vibration in main reduction gear or shaft
• B. Lock unlock shaft
• C. Hot bearing main reduction gear
• D. Major lube oil leak

Answer: (A)

NVRG identifies a mechanical symptom in the propulsion system, specifically an unusual noise or vibration coming from the main reduction gear or its shaft. This points to potential faults in the gear train—such as bearings, gears, shafts, or alignment issues—and signals the need for prompt inspection and corrective action to prevent gear damage. Actions would typically include vibration monitoring, oil condition checks, and a careful inspection of the reduction gear assembly and its supports. This fits best because it directly describes the observed symptom and the exact location involved. Other options describe different problems—like a shaft lock/unlock issue, overheating in a bearing, or a major lube oil leak—which are separate casualty indicators and would use different codes.

NVRG identifies a mechanical symptom in the propulsion system, specifically an unusual noise or vibration coming from the main reduction gear or its shaft. This points to potential faults in the gear train—such as bearings, gears, shafts, or alignment issues—and signals the need for prompt inspection and corrective action to prevent gear damage. Actions would typically include vibration monitoring, oil condition checks, and a careful inspection of the reduction gear assembly and its supports.

This fits best because it directly describes the observed symptom and the exact location involved. Other options describe different problems—like a shaft lock/unlock issue, overheating in a bearing, or a major lube oil leak—which are separate casualty indicators and would use different codes.