If a main propulsion shafting arrangement is such that a strut and strut bearing is required, what is the name of the section of shafting that passes through the hull penetration to the closest water-tight bulkhead?

Correct Answer: Option D — Stern tube shaft

The stern tube shaft is the specific section of propulsion shafting that penetrates the hull through the stern tube. It connects the line shafting to the tail shaft. Proper alignment and sealing of this section are critical for maintaining watertight integrity and supporting the propeller load per 46 CFR requirements.