The 44-foot motor lifeboat was the standard workhorse of the United States Coast Guard (USCG) rescue boat fleet. The 44′ MLB has been replaced by the 47′ MLB. The boats are powered by twin diesel engines, that each power a separate propeller. The propellers are protected by the hull, to help prevent them being damaged if the boat runs aground. The boats have air-tight compartments forward and aft of the steering station. The aft compartment is designed to hold litters to strap in injured people, while the forward compartment hold uninjured rescues.