FIRST GLIMPSE OF THE ROTATION PLAN.

And it is a year, dammit.

U.S. Army leaders are preparing to announce as early as Wednesday a plan to start relieving exhausted troops in Iraq with thousands of soldiers from U.S.-based units and an additional 10,000 National Guardsmen who will be called to active duty.

The deployments will be part of a detailed, two-year plan to make certain that units in Iraq, Afghanistan and other countries where the United States has peacekeeping forces are rotated home after one year.

Military informants told Knight Ridder that Acting Army Chief of Staff Gen. John Keane will designate both active-duty and Army National Guard units to be placed on the list to deploy to Iraq. The informants spoke on the condition of anonymity.

The plan will require the call-up of two specially trained "enhanced brigades" of the Army National Guard for one-year tours in Iraq, in addition to three active-duty brigades also destined for Iraq as replacements. The 1st Cavalry Division at Fort Hood, Texas, will play a key part in Keane's rotation and assignment plans.

The three active-duty brigades likely to be tapped for Iraq duty this year are a brigade of the 82nd Airborne Division at Fort Bragg, N.C., a new experimental Stryker armored vehicle-equipped brigade of the 2nd Division based at Fort Lewis, Wash., and a brigade of the 1st Armored Division based at Fort Riley, Kan...

The scramble to find replacement units for Iraq duty is stark evidence of how thin the 480,000-strong American Army is stretched.

Of its 33 active-duty brigades, 21 are deployed overseas: 16 in Iraq, two in Afghanistan, two in South Korea and one in Bosnia. All but three of the rest either are preparing for one of those missions, recovering and retraining after one of those missions, or held in reserve.