Famous engineer, Charles Bombardier has presented Seataci - a luxury cruise ship that could navigate in shallow waters with an eco-friendly propulsion system. Bombardier sees the potential in mimicking the cetacean by propelling the yacht with whale tail-inspired technology.

Whale tails could prove more efficient than propellers, according to Bombardier, generating less underwater noise, and allowing the ship to sail in shallower waters without damage to the hull.
The Seataci would submerge its main hull with a water ballast system. Pods on both sides of the hull would help stabilize the ship. A hydraulic system would link the two, and double as a dynamic suspension. The yacht’s crew and guests would be able to travel to those pods at any time during the cruise, and passengers could use them as galleries to get different views from the yacht.

Bombardier admits that this is an early version of the concept, and more developed ones must account for weight, water displacement, materials, ballast, and the practicalities of a new sort of propulsion.
Seataci concept images by Martin Rico