Inboard, in the context of marine engines, refers to a configuration where the propulsion system is located within the interior hull of the boat, typically central to the vessel. Unlike outboard motors which are affixed to the stern (back end) of a boat, inboard engines are integrated into the yacht, providing a lower center of gravity and better balance. This arrangement also frees up space at the stern for other features and provides protection for the engine from external elements. The propulsion force in inboards is transmitted through a drive shaft that extends from the engine to a propeller situated beneath the hull.

1. The yacht we were sailing with had an inboard engine, so it was located inside the main body of the ship, away from the visible areas. 2. Instead of the typical set-up where the engine is attached to the stern, the speedboat featured an inboard design, housing the engine within the craft itself. 3. The luxurious yacht, besides boasting a stunning interior, was equipped with an inboard engine, which enhanced the sleek profile of the watercraft and reduced noise. 4. Our new watercraft has an inboard engine, which is less noticeable and offers a smoother ride compared to outboard styles, where the engine hangs off the back of the stern. 5. The Mariner X45 uses an inboard engine configuration, leading to better weight distribution and preventing any engine noise from reaching the cabin area.

Fun Fact: Inboard motors, which are engines installed within the yacht instead of being attached to the stern, introduce a series of advantages that make them a popular choice for many boating enthusiasts. Aside from providing better balance and easier maneuvering, they are regarded for their efficiency and quieter operation. But what is particularly interesting is their unique configuration. Rather than directly driving the boat’s propeller as with outboard engines, inboard motors make use of a drive system - typically a shaft drive. This allows the engine to be placed anywhere within the yacht, usually at the vessel's center for optimal weight distribution. This inboard setup, utilized by many larger yachts and commercial boats, leads to improved stability and performance, especially in rough waters. Truly, inboard engines demonstrate a sophisticated blend of engineering and naval architecture.