May 8,2008: Most of the dozen MV-22 tilt wing aircraft the U.S. Marine Corps recently used for six months in Iraq, are being brought back to the United States. There, they will be partially taken apart to determine exactly how much wear and tear was suffered during that service in the Iraqi desert.

The MV-22s proved easier to maintain than the CH-46 aircraft they are replacing. The MV-22s needed 9.5 man hours ofmaintenance for each hour in the air, versus 24 hours of maintenance for each hour the CH-46s fly. These helicopters are all over twenty years old, which adds a few hours to their maintenance requirements. While the MV-22 required less maintenance than expected, the dust and sand in Iraq led to some engines being replaced earlier than expected.

The MV-22s can carry 24 troops 700 kilometersat 390 kilometers an hour. The CH-46E helicopter can only carry 12 troops 350 kilometers at a speed of 135 kilometers an hour. The V-22 can carry a 10,000-pound external sling load 135 kilometers, while the CH-46E can carry 3,000 pounds only 90 kilometers.

The MV-22s were only fired on twice in Iraq. Once by a machine-gun, and the second time by an RPG. In neither case was the aircraft hit. The high speed and altitude (about 9,000 feet), kept the aircraft out range of these weapons. Helicopters fly lower and slower. To do otherwise would further reduce the range of a helicopter.

Many marine commanders want the MV-22 in Afghanistan, where it would operate more effectively in the thin air of the mountains than the helicopters currently used. But the marine brass want to see the results of the tear down inspection before risking that. The marines still have a dozen MV-22s in Iraq. And SOCOM is planning on sending some CV-22s to Afghanistan before the end of the year.