Boeing is under scrutiny, and the heat is about to intensify on Wednesday, when a hearing will be held by the Senate Commerce Committee about the planemaker's $21-billion leasing deal with the U.S. Air Force for 100 B767 aerial refueling tankers. A report issued last week by the Congressional Budget Office concluded that "the proposed transaction would essentially be a purchase of the tankers by the federal government but at a cost greater than would be incurred under the normal appropriation and procurement process." The Seattle Post-Intelligencer reported Friday that Boeing may have had improper access to information about Airbus's competing proposal for the tanker deal. Boeing denied that allegation. Sen. John McCain (R-Ariz.), a longtime vocal critic of the lease -- which he has termed "corporate welfare" for Boeing -- will preside over the hearing. Boeing has already been in trouble for "industrial espionage" this summer. Last month, the Pentagon revoked a billion dollars worth of contracts with Boeing for satellite launches and banned it from similar work, saying the company resorted to industrial espionage against Lockheed Martin. In that matter, two former Boeing managers have been charged in federal court with conspiracy to conceal and possess trade secrets, and Lockheed Martin has filed suit against Boeing for damages. However, the Air Force already has made an exception to its ban to award Boeing a $57 million contract for satellite-launching work, the Seattle Post Intelligencer reported on Saturday.