JACKSONVILLE, Fla. (AP) _ A Florida teen-ager Sunday became the youngest pilot to fly coast to coast solo when he arrived in Jacksonville less than 24 hours after leaving San Diego.

''I wasn't nervous at all. If I got into trouble, I could have just landed,'' said Thad Mitchell, who turned 16 Saturday.

He said the cockpit was warm on the last leg because he forgot to open a vent. ''I'm a little tired and overheated.''

The trip made Mitchell the first pilot of any age to make his first solo flight a transcontinental trip, according to the National Aeronautics Association, which sanctioned the undertaking.

Mitchell, who lives in Pensacola, arrived at Jacksonville International Airport about 3 p.m. EDT in a single-engine Mooney 201. He had departed from San Diego at 4:55 p.m. EDT Saturday after waiting nearly eight hours for skies to clear.

The boy made refueling stops in El Paso, Texas, and Lafayette, La.

Mitchell is two years away from being licensed to fly with instruments, and must rely on visual flight rules. Because of that, he said, he cannot fly through clouds.

Flying ahead of Mitchell in a twin-engine Piper were his father, Mark; Billy Hattaway, his flight instructor for nearly four years; and Dick Bennett of Pensacola Aviation.

Younger pilots have flown across the country with instructors, but federal regulations prohibit solo flights until the age of 16.

Mitchell has logged 100 hours of flying time and flew across county with another pilot at age 13.