Federal officials are investigating the deadly crash of a small plane in Chambers County over the weekend. The plane reportedly went down late Saturday afternoon near FM 1724 just south of I-10.Search crews started looking for the plane on Saturday night and found the wreckage on Sunday. The pilot and passenger were dead at the scene.They've been identified as Larry Motte of La Porte and his grandson from Austin. The National Transportation Safety Board and the Federal Aviation Administration are investigating the crash