A pilot killed when his twin-engine plane crashed in a bean field in Will County had been inspecting an oil pipeline, according to his business partner.



Lary Diffley, 74, was flying solo in a twin-engine Beech Baron over the Enbridge oil pipeline when the plane went down shortly before 3 p.m. Tuesday near the town of Manhattan, officials said.



Diffley had been in radio contact during the flight with the oil company that contracted with him to inspect the pipeline, according to Mark Shough, vice president of Bemidji Aviation in Minnesota, a company he co-owned with Diffley.



Wreckage from the plane was spread over 500 yards, according to Will County sheriff's spokesman Ken Kaupas, who said one of the engines was found about 300 yards from the plane.



"We have quite a debris field. . .There had to be a great deal of force associated with this crash when he first touched down," Kaupas said.



He said there did not appear to be any fire from the crash and no smell of fuel.



Elwood resident Hank Delair said he saw the plane shortly before it crashed. The contractor was cleaning a ditch southeast of the scene about 2:30 p.m. when he saw the plane make a turn overhead. He said planes patrol the Enbridge oil pipeline once or twice a week.



Shough said he and Diffley bought the aviation company in 1970 after the two met in the National Guard. Shough remembered Diffley as a "superb pilot" who was fair, generous and conscientious.



Bemidji Aviation employees issued a statement expressing sympathy to the Diffley family.



Officials from the Federal Aviation Administration and the National Transportation Safety Board are expected to begin their investigation Wednesday, said Isham Cory, the spokeswoman for the FAA.

