![ZF Marine](https://www.yachtingmagazine.com/uploads/2021/09/zf_project_disruption1-1024x514.jpg)
ZF Marine introduced its Project Disruption concept at the Fort Lauderdale International Boat Show. The propulsion technology is contra-rotating for conventional inboard shaft-line applications — a way to change the existing constraints of optimizing propeller diameter with gear ratio.
“For many years there has been little innovation in inboard shaft-line technology,” Keith Stanley, ZF Marine’s pleasure craft product line manager, stated in a press release. “ZF saw the opportunity to bring all the benefits of contra-rotating propellers to this most traditional of propulsion systems.
![ZF Marine](https://www.yachtingmagazine.com/uploads/2021/09/disruption_-_2-1024x509.jpg)
The concept is intended to interface with a standard ZF marine transmission. It includes a strut-housed underwater gearbox that transmits power to two contra-rotating propellers.
ZF Marine says the solution increases efficiency and acceleration, and lets boatbuilders consider a wider range of transmission ratios than what is possible today, given propeller-sizing constraints for single-prop shaft lines.
How the system might be used in the future: It is designed to scale to larger propulsion packages as well as hybrid applications.