After the gunboats were completed but before their crews were filled out, several of them were pushed forward into the Battle of Fort Henry, February 6, 1862. The boats involved sustained some minor battle damage, but they achieved a complete victory unassisted by the Army. Their success at Fort Henry engendered exaggerated opinions of their effectiveness that were dashed only a week later. At the Battle of Fort Donelson, February 14, 1862, four of the gunboats bombarded the fort and received return fire. All four gunboats were forced out of action by damage they sustained, although the armor minimized casualties.