Bay-class icebreaking tug
（重定向自Icebreaking Tug）
![](/Images/godic/202501/19/Coast_Guard_cutter_Thunder_Bay4200.JPG")
![President George Herbert Walker Bush tours Katmai Bay (WTGB 101) with commanding officer Coast Guard lieutenant Sandra L. Stosz in 1990.](/Images/godic/202501/19/ADM-Stosz0014200.jpg")
The USCG Bay-class icebreaking tug is a class of 140-foot (43 m) icebreaking tugs of the United States Coast Guard, with hull numbers WTGB 101 through to WTGB 109.
They can proceed through fresh water ice up to 20 inches (51 cm) thick, and break ice up to 3 feet (0.91 m) thick, through ramming. These vessels are equipped with a system to lubricate their progress through the ice, by bubbling air through the hull.