The time for celebrating the founding and freedoms of the United States is the perfect time for Americans to symbolically proclaim, once again, that terrorists can't bow the nation's spirit, he said.

"It's an opportunity to tell the perpetrators of 9/11 and terrorists you didn't win. We're still here. We're not going away. We're not going to give up our way of life," said Heidenberger, who lives in suburban Maryland.

Heidenberger speaks from experience.

On Sept. 11, Michele Heidenberger, his wife of 30 years, was a flight attendant aboard the American Airlines flight that was commandeered into the Pentagon.

Three weeks later, Heidenberger returned to his job as a pilot for U.S. Airways.

His two children initially resisted the idea, but he told them it was important.

"If I change the way I live, they will have won," he remembers telling them nearly eight years ago.

This morning, Heidenberger will join first responders and relatives of other people killed on Sept. 11 at the Newseum in Washington. There they will sign a beam that's to be installed at the National September 11 Memorial and Museum being built in Manhattan at the World Trade Center site.

Today and tomorrow, the public is invited to sign the beam and to write "notes of hope" that will be placed in the museum's archives.

The New York City museum is under construction and is expected to open Sept. 11, 2011.

The Sept. 11 tribute steel beam is about 37 feet long and weighs nearly four tons, according to information from museum organizers.

Museum officials have taken beams to 27 states since 2007 to let people become part of the museum that will remember not only those killed in New York City but also those killed at the Pentagon and in a field in Pennsylvania.

Heidenberger was among the family members who helped get the Pentagon Memorial built and has been thrilled to see the constant stream of visitors to that site since its dedication last Sept. 11.

It's important to move on with our lives, he said, but it's also important to never forget.