April 29, 2010:
The United States is sending the largest helicopter force in the world to Afghanistan. By itself, U.S. Army aviation would be one of the largest air forces in the world. The U.S. Army has 19 CABs (Combat Aviation Brigades). Eleven are active duty units, and eight are from the reserves. These units, which contain, on average, 2,700 troops and 120 aircraft (nearly all OH-58 scout, AH-64 gunship and UH-60 and CH-47 transport helicopters) are being worked hard. While the withdrawal of troops from Iraq is reducing the number of troops overseas (despite a buildup in Afghanistan), a record number of CABs are staying overseas. For the next few years, about a third of the CABs will be overseas at one time. That's fifty percent more than in the last few years. To help support that, two additional CABs are being formed. One will be assembled from existing helicopters not assigned to CABs, while the other will be built from scratch. This will cost $6.6 billion. In addition to this, hundreds of heavy (1.5 ton Sky Warrior) UAVs are being added to the CABs. The army is also reorganizing the CABs, which currently come in three types; light, medium and heavy, into "Full Spectrum" units that contain a mix of different helicopter types.
Afghanistan operations use helicopters more than in Iraq, especially for getting casualties to field hospitals. These medevac (medical evacuation) choppers have to travel farther than in Iraq, where the battlefields were closer to major bases. Because of those longer distances, more helicopters are needed to deal with the additional travel times.
The CABs have come a long way in the past few decades. Current American combat divisions have 25-30 battalions assigned, with half of them being combat units. These battalions are organized into seven brigade size organizations, plus the division headquarters (which often controls the Military Intelligence battalion, Signal Battalion and several company size units.)
During the 1990s, American army combat divisions underwent some subtle changes in organization and operation. One of the more noticeable differences has been the appearance of the "fourth brigade." Since the 1960s, Army divisions referred to their "three brigades" to mean the three brigades that contained their infantry and armor battalions. But in the 1980s, the aviation battalion the divisions had since the 1960s, was expanded to an aviation brigade. In the 1990s, it became customary to assign the division reconnaissance battalion to the aviation brigade as well. This meant that a brigade that usually had a transport helicopter battalion and an attack helicopter battalion now had a ground unit (the cavalry squadron, which was a battalion size unit). In some divisions, the aviation brigade sometimes had a tank or infantry battalion assigned as well, at least for training exercises or combat operations. During the 1990s, tank and mechanized divisions were given two more engineer battalions, with the three engineer battalions now organized into an engineer brigade. Although these are combat engineers, the three battalions are usually assigned to one of the four combat brigades. There are two other "support brigades"; the divisional artillery (with four artillery battalions) and the divisional support command (with six or more support and maintenance battalions.) Manpower in US divisions now runs close to 20,000 troops with the attachment of additional artillery and aviation battalions. Sometimes yet another combat brigade is attached as well.
In the last decade, the division underwent another change, with the brigades getting more support units, and the division being like the old corps headquarters, controlling a more varied mix of brigades (depending on the situation.) With CABs no longer just the "fourth brigade" in divisions, the number of CABs grew, and that growth continues.