The F-4 was a Plunger-class submarine that met its fate in Hawaiian waters in 1915 due to a mishap while conducting diving tests. This incident raised concerns about submarine safety protocols and design specifications of the time. After submerging, the F-4 encountered difficulties that led to its sinking, which was attributed to a design flaw that compromised its diving capability. Efforts to locate and recover the vessel began promptly, as the U.S. Navy understood the significance of retrieving the lost submarine, both for the investigation into the design issues and to uphold the integrity of naval operations.

On August 29, 1915, after weeks of rigorous salvage operations, the US Navy divers successfully raised the F-4 from the depths, showcasing advancements in underwater salvage technology and techniques. The operation required a skilled team of salvage divers who employed innovative methods to bring the sunken submarine to the surface, a delicate task that involved extensive planning and coordination. The successful recovery was not only crucial for understanding the circumstances surrounding the loss but also played a vital role in shaping future submarine design protocols and safety measures to prevent similar incidents in the future.

The retrieval also prompted increased scrutiny of submarine operations and the need for regular assessments of submarines' capabilities. The F-4's incident underscored the importance of ongoing developments in naval engineering, leading to enhanced safety features and operational guidelines for future generations of submarines within the U.S. Navy.