The Harpoon missile, named after a spear and used to hunt whales and other large sea creatures, originated from a 1960s United States Navy (USN) programme to develop anti-ship missiles to target “whales” (naval slang for submarines). However, the sinking of the Israeli destroyer INS Eilat by Soviet Styx anti-ship missiles fired from Egyptian missile boats during the 1967 War of Attrition made the USN recognise the need for a dedicated anti-ship missile system. As a result, the original Harpoon project with defence contractor McDonnell Douglas (now known as Boeing Defense, Space & Security) was repurposed in the 1970s as an all-weather anti-ship missile system.
This launcher would have carried 4.75-metre-long Harpoon missiles that each weighed 681 kilogrammes, making both the Harpoon launcher and its missiles bulky objects. The missile’s weight allowed for a significant amount of firepower from each missile, while other features enhanced the Harpoon’s accuracy and range. Designed for over-the-horizon engagements or when targets are beyond the line of sight, the Harpoon missile relies on onboard guidance systems and active radar seekers to narrow down its targets.
The Harpoon missile came to the attention of the Republic of Singapore Navy (RSN) in the late 1970s due to concerns that the Gabriel missile’s shorter radar horizon range or line of sight from the radar to the horizon was a significant limitation. This became more pronounced when another regional Southeast Asian navy acquired a longer-range active homing missile with advanced fire control radar systems, which had more advantages over the Gabriel missile. Due to these factors, the RSN decided to order the Harpoon missiles to replace or complement the Gabriel missiles on the Navy’s missile gunboats and missile corvettes.