The U.S. Army has made great strides in improving the reliability of its Apache attack and Black Hawk transport helicopters. Over the last few years upgrades and improved components has increased the average time between failures from 400 flight hours to 1,140. As a result, stocks of repair parts were decreased. Then came the Iraqi campaign. Combat damage to the Apaches and heavy use by the Apaches and Black Hawks in sand storms, and the hot and dusty Iraqi climate, has caused a lot of unanticipated damage and wear and tear. As a result, it's going to cost over half a billion dollars in new spare parts, and up to 24 months, to get hundreds of helicopters in the same shape they were in before the Iraqi operations. The helicopters performed well, and they were designed to take damage and heavy wear without failure. But eventually, repairs have to be made and worn parts replaced. The bill has come due.