SCRANTON, Pa. (AP)—A full scale Air Force investigation is underway today into the crash of a C-119 cargo plane that re portedly blew apart in the sky Saturday and then plunged into a rural home and a small lake killing the co-pilot and a boy on the ground. The pilot is still missing and may be in Lake Henry, where a nose section of the giant craft was found. The search for An thony Banakus, an Air Force Reserve major from Brooklyn, N. Y.,spread over, the North eastern Pennsylvania area now locked in freezing temperatures. Killed in the crash were Capt. William J. Garin, 35, West Hart ford, Conn., the co-ptet, and 15- year old Robert Coates who had been standing outside his home apparently watching the plane’s screaming descent. Garin’s body was found hang ing from a tree by his para chute. Young Coates died shortly after the crash of severe burns over most of his body. Three persons were injured— one crew member, Yachim Ho rochuck, 45, Springfield, Mass.; Mrs. Roberta Coates, 37, the dead boy’s mother, and Martin F. Memolo, 53, Scranton, a fam ily friend who was outside the house. Hector Coates, the father, two daughters and another son, and the family’s housekeeper escaped injury. Mrs. Coates, who was inside the house, and Memolo are in serious condition. The plane was on a training mission from Bradley Field, near Hartford, Conn., to Bing hamton, N. Y., when it crashed. Holochuck said one of the “flying boxcar’s’” two engines “blew up.. it tore the mount ings right off...our radio con nections were torn out, too, so we decided to bail out.’ Holochuck, an Air Force civ ilian employe, said he was just “ducky” in getting down by par achute. “They told me to go first,” he said in an interview at Scranton State General Hospital. “It must have been around 2,000 feet, I never knew what happened to them. I was worried about where I would land and I was watching as I went down. I ended up in some trees. They were maple trees. It wasn’t too bad.” The Air Force investigating team, headed by Brig. Gen. Ro yal Hatch, commander of the 1st Air Force Reserve Region, Newburgh, N.Y. told newsmen “the Air Force is deeply con cerned about the Coates family and we'll do everything we can for them.”