The National Transportation Safety Board is focusing its investigation on the engines of a Piper Navajo plane that crashed Wednesday night on Lanai, killing three people and injuring three others. Two of the plane's engines have been airlifted from the wreckage. Investigators will examine the pieces to determine if there was some kind of problem. An NTSB spokesman says the debris field is 500-feet long and all of the components of the aircraft are accounted for.