As the U.S. shifts more of its troops to Afghanistan, they are finding that the different terrain, and distribution of enemy forces, is causing some serious problems. The biggest problem is transportation. In Iraq, a lot of the fighting was concentrated in the big cities. There, the availability of many armored vehicles, and night-vision equipment, enabled American troops to rapidly chase down and outmaneuver the enemy. In Afghanistan, the enemy is largely out in the countryside. There are fewer roads, and then there are the mountains (which are harder to get up using vehicles, and are often so high that the thin air prevents helicopters from carrying all they are capable of.)
The problems are acute for the SOCOM (Special Operations Command), which has been shifting it commandos and support forces from Iraq (where it had 5,500 personnel last year) to Afghanistan (where it had 3,000 troops). The ratio is being reversed. Most American allies have moved all their commando forces from Iraq to Afghanistan, where they not only do what they were trained for, but also train Afghans for special operations tasks. This has already been done in Iraq, where it worked quite well.
What did not work in Afghanistan was getting SOCOM operators (Special Forces and SEALs) around via ground vehicles. SOCOM troops rely on speed and surprise. That is often only possible in Afghanistan when you use helicopters. SOCOM never has enough helicopters. In Iraq that was less of a problem because SOCOM could borrow helicopters from the army. But in Afghanistan, the army has more emergency situations requiring helicopters, thus creating more situations where the choppers are simply not available for SOCOM operations. The result is that SOCOM cannot carry out all the raids and long distance reconnaissance missions that it has troops for. SOCOM troops can be moved around via C-130s, but that is time consuming, and there are not always airfields where you most need them. SOCOM operators, and some of their gear, can be parachuted into remote places, and that is being used much more than it was in Iraq. But this is still not replacement for helicopters.
The big problem is the shortage of all SOCOM aircraft (some 300 MC-130s MH-53s AC-130s MH-6s MH-60s CV-22s and a few other types). What it comes down to is that the aircraft are worn out from heavy use and combat losses. SOCOM operates 31 MH-47Ds and Es (which have additional navigation gear.) These are being upgraded to MH-47F standards, and the fleet expanded to 61 helicopters. But the expansion and refurbishment program cannot keep up with the demand in Afghanistan. Worse, there's never been enough logistics support to service all the jobs SOCOM is called on to do.
In response, SOCOM has improvised as much as possible. They borrow aircraft and logistics support from other units. SOCOM is a high priority outfit, and can often get some of what they need. When SOCOM is providing specialized support for the combat units they borrow resources from, they don't have a problem. However, when it's a pure SOCOM mission, the army and air force are not as eager to part with scarce resources. What it means is that troops are operating at less than peak efficiency because they don't have all the tools they need to get the job done. Missions get cancelled, and opportunities are lost.
SOCOM is a flexible outfit, and adaptations are being made. More commando operations are being done using ground transportation. More troops, and equipment, is being parachuted in. SOCOM is even bringing in UAVs that can carry supplies. SOCOM is all about innovation, and a helicopter shortage is just seen as another opportunity to be creative.