There is no basis for believing that insurgents' recent success in shooting down U.S. helicopters in Iraq means they have developed new attack methods or discovered new U.S. vulnerabilities, the Army's vice chief of staff said Saturday.

"I see no change in trends" on the part of the insurgent's targeting efforts, "and I see no capability gaps" on the part of U.S. forces, Gen. Richard Cody said in an interview en route to this air base north of Kabul, Afghanistan's capital.

Cody said all U.S. helicopters in Iraq recently received upgraded defensive systems to protect them against known threats like anti-aircraft missiles, although he acknowledged that helicopters on combat missions face inherent dangers, including small arms fire if they fly low to avoid being targeted by missiles.

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"We've been studying the heck out of this thing," he said, referring to the crashes, which began in January with the shootdown of a Black Hawk helicopter in which all 12 U.S. soldiers were killed. Later in January two Apache attack helicopters were shot down, apparently by small arms fire, killing two in each.

Two U.S. private contractors' helicopters also were shot down last month.

"I think people are making too much about this," Cody said, while stressing that he personally and the Army as an institution take each loss seriously and are constantly looking for ways to avoid combat losses.

Cody met with soldiers of the 4th Brigade, 82nd Airborne Division, which arrived in Afghanistan in recent weeks. In a session with pilots and others from the brigade's combat aviation unit, which flies Apaches and other choppers, he stressed the importance of remaining vigilant against insurgent attacks.

"As soon as you get predictable, as soon as you get a little bit complacent, either the enemy will get you or this terrain will get you," he said, referring to the rugged, often mountainous landscape in which they fly.

Pilots in Afghanistan have not suffered any shootdowns recently.

Gen. Peter Pace, chairman of the Joint Chiefs of Staff, told Congress last week that it was not clear whether the insurgents in Iraq were using new tactics and techniques or whether the string of shootdowns simply was a matter of the odds catching up to helicopter pilots who fly every day in dangerous conditions.

Teams of military specialists are reviewing in detail the circumstances surrounding each attack, starting with the 24 hours that preceded each one, to see what may have been overlooked in the available intelligence picture — from insurgent movements to weather conditions to other flight-related factors, Cody said.

Cody, 56, a career helicopter pilot who flew an Apache attack mission on the opening night of the 1991 Gulf War, said it should not be surprising that helicopter operations in Iraq sometimes encounter a rash of difficulties. He said U.S. chopper pilots have flown more than 1.4 million hours in Iraq and Afghanistan since 2001 and have lost a little over 100 aircraft.

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