F-35 Hit Over Iran? Hi-Tech Solution To Low-Tech Problem Likely Backfired

Stealth is a promise, not a guarantee. The US Air Force's F-35A Lightning 2 is the most expensive weapons programme in history, built around the premise that it can slip through the most contested airspace undetected.

Despite that, an F-35A was forced to make an emergency landing at an undisclosed American base in the Middle East on Thursday after flying a combat mission over Iran, the Pentagon has confirmed. Iran's Islamic Revolutionary Guard Corps (IRGC) has claimed it struck the aircraft. The US military said it is investigating the claim.

Central Command (CENTCOM) spokesperson Captain Tim Hawkins said the F-35A was flying a combat mission over Iran when it was forced to divert. The aircraft landed safely and the pilot is in stable condition.

While nothing concrete is known whether Iranian fire forced the landing or what weapon Iran used, the IRGC released a video through Iran's Fars News Agency claiming to show a missile striking the F-35 on its port side.

NDTV could not independently verify the authenticity of the video.

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If confirmed, it would mark the first time a US crewed aircraft has been struck by Iranian fire since Operation Epic Fury began on February 28. The incident is also more significant for what it reveals about the F-35's vulnerabilities than for the tactical damage alone.

The aircraft's stealth capabilities are calibrated primarily to defeat radar-based detection systems; it is shaped to scatter radio-frequency emissions and coated with materials that absorb them.

What it cannot do is eliminate its heat signature entirely.

Iran has developed air defence systems that use passive infrared sensors rather than radar to target aircraft. This method had already proved effective in Yemen when used by Iranian-backed Houthi rebels.

Passive systems are particularly dangerous because they emit no radio signals of their own. A radar-warning receiver on an aircraft detects incoming radar emissions, as against a passive infrared tracker that is silent right up to the moment of impact. These improvised or jury-rigged systems provide little to no early warning of a threat, let alone an incoming attack.

While the F-35A carries its own Distributed Aperture System, which is a network of six infrared cameras providing 360-degree situational awareness, detection and evasion are different problems.

The Houthi rebels, armed with far cruder systems than what Iran has, had already shown this gap. US F-35s flying against Houthi air defences were forced to take evasive actions in order to avoid being hit by surface-to-air missiles.

The trajectory of Operation Epic Fury has compounded this exposure. General Dan Caine, Chairman of the US Joint Chiefs of Staff, told reporters that US aircraft are now flying farther east and penetrating deeper into Iranian airspace. This region is where Iran's road-mobile air defence systems that are hard to locate and destroy are concentrated.

Road-mobile systems can be repositioned after each engagement and concealed in ordinary terrain. They can be hidden virtually anywhere and will remain a threat on the battlefield long after fixed air defences are destroyed.

Non-stealthy A-10 ground attack jets and AH-64E Apache helicopters are operating along the Iranian coast over the Strait of Hormuz in a sign that the US considers Iran's western airspace manageable and safe. Iran's eastern interior, however, is a different world.

The US has so far lost over a dozen military aircraft since the war began. Three F-15E Strike Eagles were downed in a Kuwaiti friendly fire incident on March 2. A KC-135 Stratotanker crashed in western Iraq on March 12, killing all six crew.