Flight instructor William McAdams vanishes after stealing plane at Palo Alto, California

A FLIGHT instructor facing serious assault charges has vanished over the Pacific Ocean after stealing a four-seater plane in Califoia.

William McAdams was caught on surveillance cameras at Palo Alto Municipal Airport in the city of Palo Alto, Califoia, on May 8, before he flew away in a stolen Cessna G1000 Skyhawk.

Flight instructor ... William McAdams is due in court on June 2 facing charges of second-degree aggravated battery with a weapon (dating violence) and misdemeanour battery (dating violence). Picture: Facebook Source: Facebook

In a Facebook post shared on May 10 by Fly High Aviation, a flight training company owned by McAdams, it said that Palo Alto police are conducting an investigation into his disappearance.

“The Coast Guard believe they picked up his plane’s ELT 25 miles (40km) out from the Bay Area, and shortly after near Mexican waters. They are not able to pinpoint the coordinates,” the post read.

The last known movement of the plane was a faint radar blip registered later about 115 kilometres off the Califoia coast, nearing the border with Mexico, but it wasn’t strong enough to pinpoint a location.

McAdams did not leave any note and Palo Alto Police Department have found no activity subsequently from his social media accounts, mobile phone records and bank accounts.

Simply vanished ... Flight instructor William McAdams, 24, was last seen flying over the Pacific Ocean. Picture: Facebook Source: Facebook

The FBI, the US Air Force, the US Coast Guard and the Mexican Coast Guard are all assisting Palo Alto police in the investigation. All airports have ne contacted along the coast.

“We haven’t discovered a crash. We have no evidence he landed anywhere,” Palo Alto Police’s Sgt Brian Philip told CBS San Francisco.

“There’s no record of him refuelling. We have nothing. There’s a lot of theories out there. We’re going to have to evaluate all of them.”

McAdams said he started Fly High Aviation in the Tampa Bay area of Florida before expanding to Palo Alto.

Vanished over the Pacific Ocean ... Flight instructor William McAdams has not been seen or heard of for 11 days since stealing the plane. Picture: Facebook Source: Facebook

McAdams was charged in Tampa last month with second-degree aggravated battery with a weapon (dating violence) and misdemeanour battery (dating violence).

He pleaded not guilty and was released on $16,000 bail on April.

He is scheduled to retu to court on June 2.