text: A 2006 report, prepared by RAND Corporation for the Office of the Secretary of Defense, stated that Lockheed Martin had decided not to develop an Atlas V heavy-lift vehicle (HLV). The report recommended for the Air Force and the National Reconnaissance Office to "determine the necessity of an EELV heavy-lift variant, including development of an Atlas V Heavy", and to "resolve the RD-180 issue, including coproduction, stockpile, or U.S. development of an RD-180 replacement."
  The lifting capability of the Atlas V HLV was to be roughly equivalent to the Delta IV Heavy. The latter utilizes RS-68 engines developed and produced domestically by Pratt & Whitney Rocketdyne.
  Atlas V Phase 2
  After December 2006, with the merger of Boeing and Lockheed-Martin space operations into United Launch Alliance, the Atlas V program gained access to the tooling and processes for 5.4 m diameter stages used on Delta IV.  A 5.4 m diameter stage could have conceivably accepted dual RD-180 engines. The resulting conceptual heavy-lift vehicle was called "Atlas Phase 2" or "PH2" in the 2009 Augustine Report.  An Atlas V PH2-Heavy (three 5 m stages in parallel; six RD-180s) along with Shuttle-derived, Ares V and Ares V Lite, were considered as a possible heavy lifter concept for use in future space missions in the Augustine Report.  The Atlas PH2 HLV concept vehicle would have notionally been able to launch a payload mass of approximately 70 metric tons into an orbit of 28.5 degree-inclination.
  The concept did not proceed onto full development, and was never built.