VESSEL REVIEW | Sadie Ann – University of Wisconsin-Superior's hybrid catamaran to take on lake research duties
The Lake Superior Research Institute (LSRI), an environmental research institute of the University of Wisconsin-Superior (UW-Superior), recently took delivery of a new hybrid catamaran research vessel built by Midship Marine of Harvey, Louisiana.
Designed in compliance with US Coast Guard Subchapter T requirements, Sadie Ann will be used by LSRI as a research vessel with facilities for collection and analysis of samples as well as a floating classroom that will embark students on educational tours, allowing them to interact directly with scientists.
Fitted with laboratory and classroom spaces
The 65- by 24-foot (20- by 7.3-metre) aluminium vessel can carry up to 49 passengers plus eight crewmembers. Facilities include a classroom with internet connectivity located on the upper deck aft of the wheelhouse, a wet and a dry laboratory (which can also be configured as an additional classroom) on the main deck, and two toilets.
The laboratories and other main deck spaces are kept comfortable year-round thanks to the vessel’s heating and AC systems.
The key equipment meanwhile consists of a hydraulic winch, two survey winches on the upper deck, a stern A-frame with a lifting capacity of 3,000 pounds (1,400 kg), a moonpool, and fold-down, water-level dive platforms that will enable embarked scientists to more easily collect samples from the water.
The aft working deck has a total area of 294 square feet (27.3 square metres).
Hybrid propulsion suited for inland waters
The vessel is fitted with a hybrid propulsion system consisting of two John Deere 6090SFM85 317kW (425hp) diesel engines, two Esco Power electric motors, Twin Disc gearboxes, and an 86kWh battery pack. This configuration can deliver a top speed of 18 knots and a range of 600 miles (970 kilometres) at a cruising speed of 12 knots.
Power for the various onboard systems is drawn from Northern Lights 25kW generator.
Operation of the vessel can be via the diesel engines only or on battery power only, ensuring operational flexibility and the ability to conduct low-emission sailings in environmentally sensitive inland waters. The engines are fed by fuel tanks with a combined capacity of 1,850 gallons (7,000 litres).
The vessel also boasts a maximum draught of only 4.6 feet (1.4 metres), ensuring safe operation even in shallow areas within Lake Superior and the St Louis River.
Sadie Ann replaces LSRI’s now-retired research vessel L.L. Smith. According to UW-Superior, construction of the new vessel was initiated by an anonymous grant of US$1 million in 2019, while the remainder of funding was provided by entities including the Swenson Family Foundation.
The vessel’s namesake is the late Sadie Ann Bashara Swenson, a UW-Superior alumna and mother of Swenson Family Foundation co-founder Jim Swenson.
