Built in 2001, by Houma Marine Fabricators Incorporated of DeHoop, Louisiana (hull #120) as the Harvey Thunder for Harvey Gulf International Marine of New Orleans, Louisiana.
Designed by the Naval Architecture firm John W. Gilbert and Associates of Hingham, Massachusetts For Harvey Gulf International Marine of New Orleans, Louisiana.
In 2014, Harvey Gulf International Marine's tug division was acquired by the Signet Maritime Corporation of Houston, Texas. Where the tug was renamed as the Signet Thunder.
Powered by two, EMD 16-645 E7 B turbo charged diesel engines. With Lufkin RS3040 reduction gears at a ratio of 5:1. Turning two, Bird Johnson 113(in) by 113(in) stainless steel propellers, mounted in kort nozzles. She is a twin screw tug, rated at 13,500 horsepower. She is also outfitted with a Marprop bow thruster rated at 500 horsepower.
Her electrical service is provided by two, 99kW generator sets. The towing gear consists of a Markey double drum towing winch, outfitted with 3,000(ft) of 2.75(in) towing wire on the primary drum, and 2,000(ft) of 2.5(in) wire on the auxiliary drum. The winch is driven by a dedicated GM 6-71 engine; as well as a 200 ton "shark jaw."