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Sierra Nevada Corp. submitted its final bid and proposal to replace the Air Force’s aging UH-1N Hueys with its upgraded UH-60 Sierra Force helicopters, the company said Monday.Other bidders include Boeing [BA], which is offering the MH139, based on the Leonardo Helicopters AW139, and Sikorsky, which is bidding the HH-60U, a variant of the UH-60M Black Hawk. Sikorsky is a business unit of Lockheed Martin [LMT].Sierra Nevada’s bid would involve buying divested UH-60A helicopters from the U.S. Army, then upgrading it…
