What is typically the longest shaft on a military ship like a DDG or CG?

The starboard shaft is typically the longest shaft on a military ship such as a DDG (Destroyer) or CG (Cruiser). In naval architecture, both the port and starboard shafts connect the propulsion systems, representing the left and right sides of the ship. However, due to the configuration of the propulsion system and the layout of the ship's machinery spaces, the starboard shaft generally has a longer length than the port shaft.

This length difference arises because the engine room and associated machinery often have to accommodate various systems and structures within the ship, which can lead to a design where the starboard shaft runs a longer course to connect the propulsion system to the propeller. The design considerations include factors such as the alignment of the engine and reduction gears, the placement of the fuel tanks, and the overall engineering layout designed for efficiency and balance.

In contrast, while the drive shaft and engine shaft are relevant terms in discussing how power is transmitted to the propellers, they do not specifically indicate the orientation of the shafts relative to the ship's structure. The drive shaft is a more general term that may refer to any shaft transmitting power, whereas the engine shaft is a specific part of the system that may not assess the physical layout of the shafts in