The Myth Of Stealth: Iran Puts US' Prized F-35's Name To The Test

A military aircraft does not just vanish into thin air. What it means when the word 'stealth' is coined with any military aircraft is that engineers have conditions under which detection becomes difficult enough to matter when the stakes are high.

1. Every aircraft returns a radar signal. The question is how much. Stealth engineering begins with geometry, such as angular, faceted surfaces that deflect radar waves away from the receiver rather than bouncing them back. The American F-117 Nighthawk, the first operational stealth aircraft, looked almost wrongly designed because it was. Those oblique angles weren't aesthetic choices, but the geometry of invisibility. A conventional fighter jet can return a radar cross-section equivalent to a small building. A stealth aircraft aims for something closer to a bird.

2. Radar-absorbent material like composites, carbon-fibre structures and specialised coating convert incoming radar energy into heat instead of reflecting it. These are not passive additions but structural decisions made at the design stage. The US' B-2 Spirit uses a flying wing configuration partly because fewer edges mean fewer radar-reflective seams. The maintenance burden is significant because the coatings degrade over time, and a stealth aircraft out of alignment is only partially stealthy.

3. Modern air defence systems don't rely on radar alone. The infrared search and track (IRST) method does not use radar, but looks at heat, particularly jet engine exhaust. To deal with this, stealth design keeps engines buried deep within the airframe. The exhaust nozzles are shaped to cool and disperse hot gases, and flight profiles are sometimes chosen to reduce heat output. The F-35's design explicitly integrates IR suppression. Becoming invisible to radar while glowing in the infrared is not stealth.

4. A stealth aircraft that uses its own radar actively is broadcasting its location. Stealth aircraft use frequency-hopping techniques to make electronic emissions difficult to detect and triangulate. Communications are also managed similarly. The discipline extends to pilots, who keep unnecessary transmissions suppressed during missions. Stealth is as much doctrine as it is physics.

5. No stealth aircraft is invisible. Low-frequency radars can detect stealth aircraft, though with reduced precision. Bistatic radar configurations, which separate the transmitter and receiver, complicate the geometry of absorption. Russia and China have invested significantly in counter-stealth detection networks partly for this reason. In the 1999 NATO campaign over Yugoslavia, a Serbian surface-to-air missile battery downed an F-117 using a Soviet-era radar that operated at a frequency the aircraft's design did not fully account for. The wreckage was recovered. China's defence attache reportedly visited the site.