The U.S. Army is going to, temporarily, use AH-64D helicopters more frequently for scouting. To support that effort, it will upgrade all its AH-64A attack helicopters to the all-weather D (Longbow) standard. Currently, there are about 500 AH-64Ds (most of them A model conversions) and about 300 AH-64As that will be converted. The D version has lots more sensors and the ability to share information quickly.
The growing use of UAVs has made the scout helicopter less essential. UAVs are cheaper to operate, more numerous and less vulnerable to ground fire (because the UAVs are either smaller, flying higher or simply more numerous than recon helicopters.) The army is still looking into getting a OH-58D (the current scout helicopter) replacement, but needs to do something fast, as many of the OH-58Ds have run up so many flight hours that they will soon have to be retired.
Late last year, the United States Department of Defense cancelled the ARH-70 helicopter, the replacement for the OH-58D. This came after two years of delays, and huge increases in costs. The army was supposed to get the first of its new ARH-70 scout helicopters by September, 2008. With nearly 400 of them to replace the elderly OH-58Ds on a one-for-one basis. That didn't happen.
The 2.8 ton ARH-70A was a militarized Bell 407. The helicopter it was replacing, the OH-58D, was itself a militarized version of the older Bell 206. ARH stands for or armed reconnaissance helicopter. ARH-70 has a max speed of 243 kilometers an hour, and max range of 577 kilometers. It was supposed to be a straightforward conversion. A new engine and tail assembly, plus adding a fire control and weapons system similar to that installed in the OH-58D. But problems were encountered, that took more time, and money, than Bell expected, to fix. If you follow defense procurement, you've heard that many times before.
The 2.5 ton OH-58D Kiowa Warrior has a top speed of 226 kilometers per hour, and a range of 241 kilometers. It has a mast-mounted sight, which carries a powerful FLIR (heat sensing camera) and a laser designator. The OH-58D is lightly armed, and usually only carries four Hellfire (anti-vehicle) or Stinger (anti-aircraft) missiles, or 14 70mm unguided (or guided) rockets.
The nine ton AH-64D Apaches are operated by a pilot and weapons systems operator. It is armed with a 30mm automatic cannon (with 320-1200 rounds of ammo and a range of 1,500 meters), plus 70mm unguided rockets (up to 19 of them) and Hellfire guided missiles (up to eight, each with a range of 6-10 kilometers). External fuel tanks can also be carried, although the AH-64 only stays in the air for about 90 minutes when just using internal fuel (that can be tripled with the maximum of four external tanks). Typically, AH-64s in Afghanistan will fly up to half a dozen sorties a day, often taking on additional ammo when they land to refuel. Apache only has a max speed of 360 kilometers an hour. But usual speed is much slower, from the cruising speed of about 280 kilometers an hour to a dead stop, while still in the air.