WASHINGTON — Four new Advisory and Assistance Brigades (AAB) will deploy to Iraq beginning this fall in the next regularly scheduled troop rotations, a senior defense official announced yesterday.

U.S. DoD Iraqi Freedom Rotation Schedule (PDF)

The brigades are specially configured Army units focused on training and mentoring Iraqi Security Forces (ISF).

The new AABs are among seven brigade-size elements whose upcoming deployments were announced yesterday. One brigade is going to Kuwait and two others to Afghanistan to replace redeploying forces, Pentagon spokesman Bryan Whitman told reporters.

Unlike traditional Brigade Combat Teams (BCT), the AABs will focus less on combat operations and more on advising, assisting and developing capabilities within the ISF, he explained. However, they also will conduct coordinated counterterrorism missions and protect ongoing civilian and military efforts within Iraq.

AABs will be about the size of a standard BCT, but will include more field-grade officers serving as advisors, and more engineering, military police, civil affairs, transportation and other capabilities to support the training and mentoring mission, Whitman said.

In addition to working as partners with the ISF, the AABs will support the State Department’s Provincial Reconstruction Teams, officials said.

The first units to be assigned the AAB mission will be the 3rd Infantry Division’s 1st and 2nd BCTs based at Fort Stewart, Ga., and its 3rd BCT at Fort Benning, Ga.; and the 4th Infantry Division’s 3rd BCT at Fort Carson, Colo.

Their pre-deployment training is expected to differ considerably from that of standard brigades, Whitman said. In addition to standard combat training, they will undergo scenario-based training and mission-readiness exercises designed to prepare them for the complex challenges they will encounter in Iraq, officials said.

Meanwhile, three traditionally configured combat brigades will deploy to Iraq in the same timeframe to replace redeploying brigades, Whitman announced. The 10th Mountain Division’s 1st and 2nd BCTs, based at Fort Drum, N.Y., and the 1st Armored Division’s 1st BCT at Fort Bliss, Texas, received their deployment orders last week.

In addition, three division headquarters will deploy to Iraq: the 3rd Infantry Division headquarters based at Fort Stewart; the 1st Infantry Division headquarters from Fort Riley, Kan.; and the 1st Armored Division headquarters at Wiesbaden, Germany.

Some overlap will occur as the redeploying elements conduct “left seat, right seat” training for their replacements, Whitman said. However, the slight increase will be temporary, with the deploying forces not expected to exceed the 128,000 troops currently in Iraq.

Plans remain on track to maintain those levels through the Iraqi elections, and then to gradually draw down the force to between 30,000 and 50,000 by Aug. 31, 2010, Whitman said.