How The B-2 Spirit’s S-Shaped Engine Ducts Hide A Bomber From Heat-Seeking Sensors

One of the key features of the Northrop B-2 Spirit that helps it reduce its Radar Cross-Section (RCS)is its S-shaped serpentine engine ducts. To a lesser extent, they also aid in the aircraft’s Infrared (IR) or thermal signature. While ducts were a major leap in stealth engine design when they entered service on the B-2, they are now expected on stealth aircraft. The F-22 Raptor, F-35 Lightning II, the Chengdu J-20, and the B-21 Raider all have them.