Saab's next attempt at anti-ship missiles to equip the Norrköping class FACs of the Swedish navy was in 1978 under the project name "RB 04 Turbo", a development of the air force RB 04E missile with a turbofan engine, changed wing configuration and start rockets to take off from land. The initial proposal was rejected as inferior to the Harpoon missile. The project, under the leadership of Hans Ahlinder, then worked out a proposal for a missile with greater capabilities and superior performance to the Harpoon. To indicate that it was a new weapon the project name was changed from "RB 04 Turbo" to "RBS-15".