• A mid-afternoon veiw down the expanse of Isle Royale National Park.  Photo taken from the Mount Ojibway Fire Tower.

    Isle Royale

    National Park Michigan

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  • Unmanned aircraft including hobbyists

    All waters and lands within the boundary of Isle Royale National Park have been closed to the use of unmanned aircraft including radio-controlled airplanes, hexacopters, and similar items. More »

RANGER III statistics

Ranger III in dry dock
Ranger III in dry dock
National Park Service


MISSION: Logistical Support of Isle Royale National Park

Length 165 feet
Beam 34 feet
Depth 15 feet 1 inch
Draft 10 feet 6.5 inches
Load Displacement 835 short tons
Crew 6 - freight, 9 passenger
Passenger Capacity 128
Cargo Capacities 100 tons dry
7,500 gallons of oil

650 cubic feet of
refrigerated and freezer

Main Engines 2 Caterpillar 3508 B;
850 BHP @ 1200 RPM
Propellers 2 Bird-Johnson Controllable
Pitch, 76" Diameter
Bow Thruster 250 HP/Hydraulic
36" diameter fixed pitch
Power Generators 2 Caterpillar 3304,
55 KW
Crane 3.1 Ton Hydraulic
30-foot boom

Did You Know?

View of the Greenstone Ridge Trail in the fall from the Ojibway Fire Tower.

The Greenstone Ridge, which forms the backbone of Isle Royale, is thought by many geologist to be a portion of the largest lava flow on earth.