The Pentagon has declared that the Evolved Expendable Launch Vehicle (EELV) project has exceeded its original projected per-unit cost by 58.4%, triggering a rigorous review under the Nunn-McCurdy program oversight law.

Through the EELV program, the government procures Atlas V and Delta IV rockets from United Launch Alliance, a joint venture of Lockheed Martin and Boeing. The cost growth was reported April 13 to Congress.

The increase resulted from several factors. The 2004 baseline called for 137 projected launches, though only 91 have actually been manifested, owing largely to delays in satellite development and procurement efforts.

“The EELV program has interdependencies with a variety of satellite programs and their production timelines,” according to an Air Force statement. Additionally, Air Force officials note a “sharply rising cost of launch vehicle propulsion systems.”

Scott Correll, Air Force program executive officer for launch, says the propulsion systems are a major contributing factor in the increase in EELV cost, based on the findings of a “should-cost” review into the program that he led. NASA’s decision to retire the space shuttle also has contributed to the cost uptick, owing in large part to a sharp reduction in work for the propulsion industry, including Alliant Techsystems, Pratt & Whitney Rocketdyne and Aerojet.

“The U.S. domestic launch industrial base, and particularly the rocket propulsion industry, is also under increased stress due to future business uncertainty,” the Air Force statement says.

Air Force officials halted selected acquisition reports (SARs) to Congress on EELV, which outline detailed program costs, in 2007 once the program entered a “sustainment” status. However, due to the cost growth since then, Congress has requested that SARs for EELV be restarted. As a result, this latest report includes all cost growth since the last SAR in 2007.