The United States has revealed that it has captured terrorist
documents in the last month, indicating that several groups have adopted a new
tactic, of going after American helicopters. Seven helicopters have crashed in
Iraq in the last four weeks. Most appear to have been hit by hostile fire. In
the last two months, attacks on helicopters has gone up 17 percent. About one
in six attacks results in the helicopter crashing.
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, providing more
targets. 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.
some of the recent 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, not the missile.
helicopter pilots have been dealing with the risk of deliberate flak traps
since 2003, and the current losses are partly the result in getting sloppy.
That means flying the same routes too often, and too predictably, makes it
easier for these ambushes to work. Helicopters can fly high enough to
avoid most ground fire, until it's time to come in and land. That's where it
becomes important to vary approach routes regularly, and unpredictably.
is not a new problem. 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). Even so, 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. A new danger in Iraq is the enemy setting up ground ambushes for
the troops (and medical teams) that rush out to the scene of a crash. Both
problems will be handled with new tactics, which will endeavor to catch the
ambushers themselves. This has led to the deaths, or capture, of many enemy
fighters in the past.