Review of copter defenses under way
Order issued in wake of fatal Chinook downing
An SH-60 Sea Hawk, the Navy equivalent of the Army's Black Hawk, fires flares in an air power demonstration. The flares can distract heat-seeking missiles.
CNN's Jamie McIntyre on stepped-up U.S. raids to find Saddam and an urgent review of military helicopters' defenses.
Family and friends recall three soldiers killed in Saturday's copter crash.
WASHINGTON (CNN) -- A review is under way of protective measures on all 620 U.S. Army helicopters deployed in Iraq and Afghanistan.
In a memo dated November 7, acting Army Secretary R.L. Brownlee suggested that cost was no object to get the "most effective defensive systems" on all helicopters, and in a handwritten postscript he wrote: "This is URGENT!"
Thirty-nine U.S. troops have been killed in five helicopter crashes in Iraq since October 25.
Brownlee's memo immediately resulted in stepped-up installation of a new anti-missile system on half of the 90 CH-47 Chinook transport helicopters in Iraq that carried an older system, like the one shot down November 2 near Fallujah, killing 16 soldiers.(Full story)
The Army's action was prompted, at least in part, by concerns expressed by Democratic Sen. Richard Durbin of Illinois in the days after the Chinook crash.
The helicopter and its pilot were from the Illinois National Guard.
Durbin's office said messages had come in after the downing from people suggesting Chinooks -- an older model of helicopter that saw action during the Vietnam War -- had sometimes been sent out without up-to-date, or even functioning, protection. (Full story)
The review also includes protective measures on the UH-60 Black Hawk, AH-64 Apache and OH-58 Kiowa helicopters.
Black Hawks vulnerable
Most of the recent crashes have involved the multipurpose Black Hawk, including Saturday's collision of two over Mosul in northern Iraq that killed 17 soldiers.
Although mechanical failure has not been ruled out, a military source said initial reports indicated one helicopter ascended to avoid groundfire.
"This caused a rotor strike with the second helicopter," the source said. (Full story)
Almost half of the Army helicopters operating in Iraq -- 290 -- are Black Hawks, which have been the workhorse of the Army fleet since they began replacing the venerable Hueys used during the Vietnam War.
With a range of 368 miles, the Black Hawk can fly much farther than the older UH-1 Huey and can carry much heavier loads, along with a full squad of 12 combat-ready troops.
And with armor that withstands projectiles up to 23 mm and armor-protective seats for the pilot and co-pilot, the Black Hawk is vastly more survivable than its Vietnam-era predecessor. Yet a single rocket-propelled grenade that hits a critical spot could bring one down.
Black Hawks already have all the latest protective systems, and there may be little more the Army can do other than employ standard tactics: Vary routes, fly at night when possible, and stay low to minimize the time an enemy can target them.
The Chinook that was struck had an older anti-missile system known as the M-130. The newer version puts out more flares that can serve as better decoys against missiles equipped with infrared tracking systems.
The unit, called the ALE-47, also can release a greater quantity of metallic particles known as "chaff," designed to confuse radar guidance systems on hostile missiles.
The flares on the new system also can be sequenced to pulse in a way that more closely resembles the pulsating heat signature of a helicopter engine, officials said.
The older system emits a constant heat trail that infrared-guided missiles could be programmed to ignore. An Army spokesman could not say whether it was working on the downed Chinook.
An Army source said all the Illinois National Guard helicopters were outfitted with flare and chaff dispensers, but several of the units were damaged during transport to Iraq. The assemblies, nicknamed "flare buckets," are mounted beneath the aircraft.
Eventually, units were taken off other departing helicopters and installed on the aircraft from Illinois. A policy change will now keep such aircraft and hardware in place to cover any shortfalls.
CNN's Jamie McIntyre and Paul Courson contributed to this story.