The roaring sounds of a B-52 bomber and other military planes will be heard over Arlington County today as part of the groundbreaking ceremony for an Air Force memorial -- the first to honor those who served in that branch, military officials said.

The national memorial, which is expected to be completed in two years, will be built adjacent to Arlington National Cemetery in an area known as the Navy Annex, said Lt. Col. Cynthia Scott-Johnson, a U.S. Air Force spokeswoman.

"This is to honor the selfless contributions of the airmen who distinguished themselves in the Air Force," Scott-Johnson said. "It is also a sculptural representation of the tremendous achievement of American air and space power."

The Air Force Memorial Foundation has raised $38.5 million and hopes to raise an additional $3 million to complete the memorial, said retired Col. Pete Lindquist, vice president of operations for the foundation.

Lindquist said the memorial will contain three stainless steel spires -- the tallest will be 270 feet -- that "gracefully and boldly soar into the heavens."

"It's almost like a sculpture," Lindquist said. "They're graceful, they're slender and they don't create a lot of mass. You will see them on the horizon. They won't disrupt the Washington, D.C., skyline. They will add to it."

The three-acre site will also have a memorial park, a parade ground overlooking the capital and "Walls of Reflection," which will depict images and the history of the Air Force.

As part of today's ceremony, a combination of vintage and modern aircraft will perform flyovers, officials said. A practice run was held yesterday.

There will be eight aircraft overhead, including a B-52 bomber, a P-51 vintage fighter plane and an F-15 and F-16 flying in formation, officials said.

Lindquist said the planes will be flying at an altitude of about 1,000 to 1,500 feet. The flight pattern, which Lindquist said was approved by the Federal Aviation Administration and the Department of Homeland Security, prompted Arlington police to issue a notice Monday informing residents of the flyovers.

"There will be noise," Lindquist said. "Some of the airplanes are big bombers. But no one should be fearful. These flyovers are very safe."

The groundbreaking ceremony is the culmination of 12 years of planning, Lindquist said, including the passing of legislation to authorize a memorial as well as securing approvals from the Commission of Fine Arts and the National Capital Planning Commission.

It was also delayed by a two-year controversy over the selection of the site. Initially, the proposal was to place the memorial near the Marine Corps War Memorial and the Netherlands Carillon in Arlington Ridge.

"There was concern that it would take away from those two memorials by having a third one," Lindquist said. But the current site is ideal, he said, because it is on a promontory that overlooks the capital.

"It's an absolutely magnificent and panoramic view," Lindquist said. "The visibility of the memorial site could not be better. It is near [Interstate] 395, where hundreds of thousands of folks will pass it on a daily basis."

The memorial will honor not only those who served in the youngest service, which was officially established as a separate branch in 1947, but also those who served in its predecessor organizations, including the Aviation Section, U.S. Signal Corps, U.S. Army Air Corps and Army Air Service.

"This represents the Air Force and its heritage organizations," Lindquist said. "We want to erect something that will give all Americans an understanding of what the Air Force did for their country."

The Air Force memorial will have three stainless steel spires that "gracefully and boldly soar into the heavens," a foundation official said.