SAN DIEGO (CNS) - The family of a 12-year-old boy who was seriously injured when a plane pulling an advertising banner crash-landed on Carlsbad State Beach on the Fourth of July filed a lawsuit today against the aerial advertising company and the pilot.

Nicholas Baer suffered a concussion and underwent emergency brain surgery following the accident. He was released from the hospital less than a week later.

The lawsuit -- filed in San Diego Superior Court against El Cajon-based Air Ads Inc., owner James Oakley and pilot Luke William Kanagy -- does not list a dollar amount for damages, said attorney David S. Casey Jr.

No one was answering the phone at Air Ads this afternoon.

Casey said the Baer family wants to find out why the engine on the small plane failed and why the pilot decided to land on the beach.

Casey said beachgoers could not hear the single-engine aircraft approach because the engine was off and the propeller was not spinning.