February16, 2007: Seven helicopters have crashed in Iraq in the last four weeks. Most appear to have been hit by hostile fire. In some of those cases, the hostile fire was carefully planned. That is, multiple machine-guns, including at least one heavy (12.7mm or larger) machine-gun were placed along a route used by helicopters, and fired in a coordinated matter. This tactic is called "flak trap," and dates back to World War II (or earlier).

The enemy has also been using portable surface-to-air missiles since 2003, including more modern models, like the SA-16 (which is similar to the American Stinger.) American helicopters are equipped with missile detection and defense (flare dispensers) equipment. Thus the most dangerous anti-aircraft weapon is the machine-gun. However, aircraft losses to ground fire have been declining every year, since 2003, mainly because of good defensive tactics. Moreover, the most vulnerable aircraft, helicopters, have been spending more time in the air. In 2005, U.S. Army aircraft (mainly helicopters) flew 240,000 hours over Iraq. That increased to 334,000 hours last year, and is expected to go to 400,000 hours in 2007. The more time helicopters are in the air, the more opportunities someone has to shoot at them.

Since 2003, the United States has lost 57 helicopters in Iraq. Most of them (29) belong to the U.S. Army, the rest are marine and civilian (mainly security contractors.) In the last year, helicopters were fired on about a hundred times a month, and about 17 percent of the time, the helicopters were hit. In Vietnam (1966-71), 2,076 helicopters were lost to enemy fire (and 2,566 to non-combat losses). In Vietnam, helicopters flew 36 million sorties (over 20 million flight hours). In Vietnam, helicopters were about twice as likely to get brought down by enemy fire. As in Iraq, the main weapons doing this were machine-guns. Today's helicopters are more sturdy, partly because of Vietnam experience, and are more likely to stay in the air when hit, and land, rather than crash.