Congressional investigators say The Boeing Company did not intentionally withhold a 1980 study on fuel pump performance in the E-4B. The 19-year-old report on fuel tank heating in a military version of the Boeing 747 was prepared for the U.S. Air Force. "The General Accounting Office investigators found no evidence of a conspiracy on Boeing's part to withhold the study," Sen. Chuck Grassley, R-Iowa, chairman of Judiciary subcommittee on administrative oversight, said Thursday. Boeing said the report was not given to National Transportation Safety Board investigators probing the 1996 TWA Flight 800 explosion because its civilian airliner division was unaware of the report prepared by the company's military unit. "That document was not withheld," Boeing Chairman and CEO Phil Condit said earlier this week. "It was a question of finding it. It was a document about fuel pump performance that in retrospect bears a resemblance but, by the way, has to do with a configuration that is entirely different (than a commercial 747) under a different use. It would not have changed the outcome of the investigation.' Company officials also dispute a charge by Sen. Grassely that it has established a "pattern of under-reporting" on safety issues.