The pilot, his wife and another couple aboard Mitsubishi MU-2B N312MA where killed when the twin turboprop crashed moments after taking off from Hillsboro, Ore., on Tuesday evening. The 1973 airplane (S/N 266) has been registered since April to Max Aviation, also of Hillsboro. Information about weather conditions at the time of the accident was not immediately available. There is preliminary evidence that the left engine was not operating at the time of the crash, but other evidence might have been damaged when, during efforts to remove the wreckage, an errant spark ignited jet fuel and the fuselage caught fire and burned. According to NTSB records, N312MA had a left-engine power loss in 1982, attributed to inadequate maintenance, and the landing gear inadvertently retracted on the airplane during a landing in 1979.