WAHIAWA — Two Army pilots whose unit is preparing for deployment to Iraq died yesterday after their helicopter crashed during a training flight at Wheeler Army Airfield, officials said.

One soldier was pronounced dead at the scene, and the second died at Wahiawa General Hospital.

The two soldiers were the only people aboard the helicopter, a two-seat OH-58D Kiowa Warrior helicopter belonging to the 25th Combat Aviation Brigade. They were conducting a general maintenance test flight when it crashed in the base airfield and hangar area, the Army said.

The soldiers' names are being withheld until 24 hours after their families have been notified.

A Hawai'i National Guard member who was at the scene said he could not readily identify the type of helicopter that had crashed because the damage was so severe. The helicopter appeared to have burned, although Col. Matthew Margotta, commander of U.S. Army Garrison Hawai'i, could not confirm there was a fire.

The cause of the accident is being investigated, the Army said in a news release.

"Our prayers and condolences are with the families of the pilots," U.S. Army Garrison Hawai'i said in the release.

The 34-foot-long Kiowa helicopter is one of the smallest in the Army inventory. It is used primarily for reconnaissance but can fire missiles, rockets and machine guns.

Margotta told reporters at Wheeler that the helicopter was on "a routine maintenance test flight" and was landing when it crashed about 3:30 p.m.

"The pilot still had control of the helicopter when it landed," Margotta said.

Both pilots on board were killed, he said.

No other information about the flight was disclosed.

Asked to talk about risks in flight operations, Margotta said, "Obviously when you fly helicopters and these guys are trained to go to combat and that's what they're preparing to do right now. So there are certain risks that's inherent in what they do and they accept those risks."

The active duty 25th Combat Aviation Brigade, with its 2,400 soldiers, is preparing for a fall deployment to Iraq and many of its members are returning from training at Pohakuloa Training Area on the Big Island and at the National Training Center in California.

The aviation brigade flies the scout attack Kiowa Warrior, UH-60 Black Hawks and twin-rotor CH-47 Chinook helicopters.

The aviation brigade had about 100 helicopters from Wheeler in Iraq on a deployment that ended in September of 2007.

In final preparation for their deployment to Iraq later his year, the 25th Combat Aviation Brigade trained throughout the Hawaiian Islands and at the National Training Center at Fort Irwin, Calif., from April 25 through May 3.

Col. Michael Lundy, who commanded the aviation brigade, said soldiers conducted more than 669 flights flying over 2,200 hours.

The Hawai'i Army National Guard has 10 CH-47 Chinooks at Wheeler. It also has some OH-58 Kiowas, but they are based out of Hilo along with Black Hawk helicopters.