Mackinaw: Propulsion

Propulsion

Six Fairbanks Morse 10 cyclinder opposed piston diesel engines form the heart of Mackinaw's propulsion plant. The engines drive integral generators, developing the electrical energy needed to power the three huge electric motors, which in turn are coupled directly to the three propellor shafts.

Each of the six diesels is rated for 1750 horsepower at 750 RPM. They are started by compressed air. The engines are organized in two compartments, two engines in a forward engine room with the bow motor, and four engines in the aft engine room along with the twin stern motors.

Image: Ampmeter 0-2,000 AMP

The two stern electrical propulsion motors are rated at 5,000 HP each. They turn 14-foot diameter propellors that weigh over 20,000 lbs. The forward electric motor is rated at 3,300 HP and turns the slightly smaller bow propellor, only 12-ft in diameter and about 14,000 lbs. It takes a considerable amount of electrical current, even at 900 volts, to turn these huge shafts, as the 2,000 ampere scale on the meter attests.