China’s stratospheric airship can detect American F-35 fighter from nearly 2,000km: study

Name: New Chinese fighter jet seen over Chengdu tacitly confirmed by military
Uploaded: 2025-02-11T05:44:36.000Z
Duration: 1 min 9 s
Description: New Chinese fighter jet seen over Chengdu tacitly confirmed by military

Chinese researchers say they found jet’s potential vulnerability in study of simulated combat involving Taiwan

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Chinese researchers say they can detect the US-made F-35 fighter jet from more than 1,800km away via its engine exhaust plume. Photo: US Air Force

Stephen Chenin Beijing

Published: 1:44pm, 11 Feb 2025Updated: 3:23pm, 11 Feb 2025

A stratospheric airship equipped with advanced infrared detection systems could identify stealth aircraft – such as the US-made F-35 fighter jet – from nearly 2,000km (1,240 miles), according to Chinese scientists.

The findings suggest a potential vulnerability in America’s fifth-generation stealth technology and mark a significant leap in China’s pursuit of anti-access/area denial capabilities.

Researchers with the Changchun Institute of Optics, Fine Mechanics and Physics (CIOMP) – a key player in China’s missile and space programmes – analysed the infrared signature of F-35s in simulated combat scenarios that would involve Taiwan. The research was published in May in the Chinese-language journal Aerospace Technology.

The team found that while the jet’s radar-absorbing coating and exterior cooled to an average 281 degrees Kelvin (7.85 degrees Celsius or 46 Fahrenheit), effectively masking it from traditional detection, its engine exhaust plume, which reaches nearly 1,000 Kelvin, emitted mid-wave infrared radiation three orders of magnitude stronger than its airframe.

By focusing on the 2.8-4.3 micrometre wavelength range – where atmospheric interference is minimal – and deploying mercury-cadmium-telluride detectors and 300mm aperture telescopes, the unmanned airship hovering at 20km could spot an F-35’s rear thermal signature more than 1,800km away when the aircraft was viewed from the side or behind.

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New Chinese fighter jet seen over Chengdu tacitly confirmed by military

However, detection from the front remained limited to 350km because of the stealth jet’s reduced forward heat profile.