In 1972 Raytheon started a Sparrow upgrade program to arm the upcoming F-15 Eagle, producing the AIM-7F. The F model replaced the older analog guidance system with a solid state version that could operate with the F-15's new pulse-doppler radar. The guidance system was much smaller, which allowed the warhead to be moved from its former rear-mounted position to one in front of the mid-mounted wings, and increased in weight to . Moving it forward also allowed the rocket engine to be enlarged, so it was replaced by a new dual-thrust engine that quickly accelerated the missile to higher speeds, and then settled to a lower thrust for cruise. The new missiles were quickly adapted for the naval role in a fashion similar to the RIM-7H, producing the RIM-7F. The new missile used the lower model designation in spite of the newer technology than the H model.