John Birkler, Paul Bracken, Gordon T. Lee, Mark A. Lorell, Soumen Saha and Shane Tierney. RAND, 16 January, 2012.
http://defensealt.org/J83lFJ

Excerpt:

For at least two decades, policymakers have expressed concerns that further consolidation could erode the competitive environment for military aircraft and degrade the industry’s abilities to develop, manufacture, and support innovative designs. The authors find that only by involving two prime contractors equally in performing RDT&E (research, development, test, and evaluation) on a new large program, such as a bomber, could DoD sustain two firms through 2020 with RDT&E funding and through 2025 with procurement funding.