The Defense Department budget could fall 30 percent in terms of inflation-adjusted, total obligation authority “from peak to valley,” following the drawdown of troops from Iraq and Afghanistan, according to the Air Force’s chief financial officer.

Assistant Secretary of the Air Force for Financial Management and Comptroller Jamie Morin told reporters March 2 at the Stimson Center that while DoD’s budget plans “don’t forecast that level of reduction,” they “certainly know it is a possibility.”

“Right now, our budget plans don’t forecast that level of reduction, including the taildown in Overseas Contingency Operations (OCO) funding,” Morin said. “But we certainly know that is a possibility and while we plan to the plan, we are aware there are risks,” such as fluctuating costs in fuel and health care coverage, he said.  “(And) there are probably more risks, more than we project, barring a major conflict.”

An Air Force graph of budget trends in fiscal year 2013 dollars, adjusted for inflation and including supplemental and OCO funding, forecasts a DoD budget decrease of 21 percent from FY ’10 to ’17, down $156 billion. The graph also projects an Air Force budget decrease of 13 percent, down $19 billion from FY ’10.

Having studied historical military drawdowns, such as post-Cold war, post-Vietnam and post-World War II, in his academic days, Morin said these drawdowns are usually a “decade-ish” in length.

Morin also said there was a tendency to engage in “wishful thinking” over which programs could survive budget reductions of these past drawdowns, like a program manager “whittling down” the cost of a program. But because of Weapons System Acquisition Reform Act of 2009, Morin said he and his team were very strict on what to include in the fiscal year 2013 modernization budget.

“My folks and our senior leadership team has enforced a lot of discipline in sort of thinking about how many things we are going to pack into the bag of our modernization budget,” Morin said in addition to being disciplined in operations and support costs.