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How do stealth aircraft reduce their radar signature?

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military aircraft Tupolev Tu-22M, a Russian variable-wing supersonic jet bomber first flown in 1969. It was designed for potential use in war against the NATO countries, where it was known by the designation “Backfire.”

Stealth aircraft reduce their radar signature through a combination of specialized materials, geometric design, and internal configuration to minimize the reflection of electromagnetic radiation back to an enemy's radar receiver.1

Design and Geometry

To direct radar energy away from the source, designers utilize specific external shapes:
* Complex Curvature: Aircraft like the B-2 Spirit use large-radius, curved surfaces to scatter radar waves.2
* Flat Planes: Aircraft like the F-117A Nighthawk utilize numerous small, flat, and carefully oriented surfaces to deflect radar energy.2
* Shape Optimization: Designers avoid right angles, sharp curves, and large, flat surfaces that would otherwise create strong radar echoes.2

Materials and Configuration

Radar-Absorbent Materials: Specialized coatings and materials are applied to the aircraft to absorb radar transmissions rather than reflecting them.12
Internal Carriage: To maintain a smooth exterior, fuel and ordnance are carried internally, and engine intakes and exhausts are set flush or low to the surface, preventing protrusions that increase detectability.12
Structural Materials: The use of carbon-fibre composites and high-strength plastics allows for structural integrity while remaining transparent or translucent to radar.2