Down Payment to Protect National Security Act of 2011 - Requires the Director of the Office of Management and Budget (OMB) to determine the number of full-time employees employed in each federal agency. Prohibits a federal agency head from hiring more than 1 employee for every 3 full-time employees who leave employment in such agency until the OMB Director makes a determination that the number of full-time federal employees is 10% less than the initial level as determined by OMB. Allows a waiver of such workforce limitation by the President for national security reasons or in the case of an extraordinary emergency.
Amends the Balanced Budget and Emergency Deficit Control Act of 1985 (Gramm-Rudman-Hollings Act), as amended by the Budget Control Act of 2011, to offset mandatory sequestration in security and nonsecurity categories in FY2013 with revenues resulting from reductions in the federal workforce under this Act.