Developed by the chinese/russian missile defense initiative the HongQi 2 is a large two-stage missile designed to intercept high-altitude targets like strategic bombers, spy planes, and nuclear devices. Its radar guidance guarantees a single-shot hit probability of 88%, but according to the American's experience in the Vietnam War, this ratio drops sharply when the missile is used in a strong electronic jamming environment. The improved HongQi 2B is said to have much improved capability against various active and passive jamming.