Missing F-35: Please contact US if you find a stealth fighter jet anywhere around you, says military

The US military Monday was in a race against time to locate a stealth jet that had gone missing after the pilot ejected, and the failure to track down the aircraft was met with both astonishment and ridicule.

After the F-35 vanished over South Carolina on Sunday, Joint Base Charleston (JBC) issued a desperate plea on social media, requesting anyone with information to come forward.

JBC indicated that, based on the last-known position of the jet, the search efforts were concentrated around two large lakes north of Charleston, suggesting the possibility of a crash.

The F-35 Lightning II jet, known for its distinctive shape and radar-evading capabilities, is highly sought after by US allies worldwide, particularly Ukraine.

However, as of Monday, the fate of the missing aircraft remained uncertain.

"We are currently still gathering information. The investigation is ongoing," a JBC spokesman told AFP.

The pilot ejected for unknown reasons and parachuted safely into a North Charleston neighbourhood — leaving the jet flying in what some called a "zombie state."

In 1989 the pilot of a malfunctioning Soviet MiG-23 ejected over Poland and the jet continued to fly on autopilot until it crashed in Kortrijk, Belgium, more than 900 kilometres (560 miles) away.

The disappearance of a highly advanced aircraft that costs at least $80 million sparked incredulous comments online.

"How in the hell do you lose an F-35? How is there not a tracking device and we´re asking the public to what, find a jet and turn it in?" said Nancy Mace, a member of Congress representing the Charleston area.

Some posted manipulated photographs of lost signs on trees, offering rewards to find the missing jet.

One post showed Ukraine President Volodymyr Zelensky posing in front of an F-35, suggesting he took it.

Since Russia invaded his country last year, Zelensky has been pressing the United States to supply his air force with the jet to give his military an advantage.

The missing aircraft was an F-35B, a variation operated by the Marines that has short takeoff and vertical landing capabilities.

The shape of its airframe, including two angled stabilisers on the back, and the use of special materials, make it harder to detect by traditional radar.

JBC spokesman Jeremy Huggins told the Washington Post that the jet´s transponder was not working and that its stealth capabilities added to the challenges of tracking it.

At least seven F-35s have been destroyed in previous crashes, due to a range of causes.