The US Marine Corps says the pilot of an F-35B stealth fighter ejected before the jet crashed in California, and was taken to a medical facility.The jet went down on Friday afternoon near the Miramar airbase in San Diego. A Marines statement called it a “Class A mishap”.That is the most severe mishap category, used when the damage totals more than US$2 million, an aircraft is destroyed or a service member killed.A single F-35B fighter jet costs about US$109 million. The statement did not include any details about the condition of the pilot, other than to say they ejected, were recovered and were being taken to a medical facility.Aerial video from a news helicopter showed a plume of black smoke rising from the wreckage in a dirt field, with multiple military and firefighting vehicles and people standing nearby.Crews work to douse a F-35 fighter jet that crashed near the runway at Marine Corps Air Station Miramar in San Diego on Friday. Photo: The San Diego Union-Tribune via APWhat appeared to be white flame retardant covered the ground, and at least one person was spraying the wreckage with a fire hose.