The Pentagon will be forced to cut spending on procurement and research and development by more than $66 billion dollars over a four-year beginning in fiscal 2016 if Congress does not block the resumption of sequestration.

DF-ST-87-06962The Bipartisan Budget Agreement passed by Congress last year lifted sequestration for fiscals 2014 and 2015 in place of budget caps, but the measure ends at the end of fiscal 2015. The Pentagon on Tuesday evening outlined in a report how its spending plans will impacted if sequestration returns.

The Pentagon would have to cut $48.3 billion in procurement spending from fiscal 2016 to 2019, lowering it to $501 billion from the originally planned $550 billion. Research and development would drop by $19.9 billion to $319 billion, according to the document.

Modernization accounts would be hit by a combined $66 billion, and spending on combat systems would fall by $18 billion.

The decline in spending on procurement would impact several major weapons programs. Notably, it would reduce the Air Force’s planned buy of F-35A Joint Strike Fighter by 15, eliminate its fleet of KC-10 tankers, divest itself of planned purchases of block 40 Global Hawk and Predator UAVs, and shrink by five the number of new KC-46A tankers planned for that period.

The Navy would scale back purchases of Arleigh Burke

-class destroyers by three and a Virginia-class sub by one as part of an eight-ship purchasing reduction. Additionally, the Navy would have to retire ships early, including an aircraft carrier, reducing the battlegroup fleet to 10.

The Navy would also cut the P-8 maritime surveillance aircraft program by six aircraft.