The plug-in hybrid excursion vessel Enhydra, delivered to San Francisco’s Red and White Fleet last September by Bellingham, Wash, shipbuilder All American Marine, features a BAE Systems HybriDrive.
Builders faced the challenge of integrating the vessel’s Cummins QSL9 410 hp diesel engine and the advanced 80 kWh battery-powered propulsion solution into a traditional marine power train.
Twin Disc distributor Mill Log Marine, which has now been acquired by Palmer Johnson Power Systems, provided the solution in the form of QuickShift MGX-5114SC reduction gears and an EC300 Power Commander electronic propulsion control that meets Subchapter K requirements.
The combination delivered the efficiency needed to complement the hybrid vessel’s sustainable fuel consumption, lessened impact on marine life and quiet operation.
“Enhydra is just another example of how Mill Log Marine and Twin Disc strive to solve our customers’ needs in marine drivetrain applications,” said Bob Shamek, Mill Log Marine key account executive. “On Enhydra, the gears have remote electric motor driven oil pumps. This allows the gear to stay engaged when the motors are operating at low speed and through zero shaft speed when changing rotation from forward to reverse.”
The QuickShift® MGX-5114SC offers a smooth, steep power curve with fast shifting, precise slow speed control and quiet operation. The 3:1 gear features an SAE J617 number 1 vertical offset, aluminum housing and minimal external plumbing. It boasts an electric GP-valve with manual override.
The Twin Disc EC300 Power Commander electronic propulsion control provides drive motor speed and rotational control, along with fault monitoring. Dual CAN bus wiring provides redundant control communications from the pilot stations to the controllers in the engine room. A monitor at Enhydra’s helm provides a graphical readout for control system fault codes, as required under Subchapter K regulations.