For 16 years, Flight 93’s cockpit recordings served as the final, collective rallying cry from the plane’s 40 passengers and crew members.

It preserved their heart and heroism – but also the “hateful” voices of terrorists who were intent on bringing death and destruction on September 11, 2001, said Patrick White, Friends of Flight 93 National Memorial president.

Soon, Flight 93’s “40 heroes” will sing in harmony, he said, from the Stonycreek Township field in Pennsylvania where the hijacked flight crashed. 

On Sunday, friends and family members of the men and woman credited for fighting back on 9/11 gathered alongside National Park Service officials to break ground – and sound – on a metallic musical monument designed to bring life to their voices once again.

The Tower of Voices project’s architect, Paul Murdoch, rang one single pre-tuned chime to commemorate the event, saying it will soon be one of 40 that will ring here – each one different, just like the lives they honor, he said.

“We’ll soon have a monument here that the world has never seen – or heard,” Murdoch said.

Wind engineers in Colorado and Australia, acoustical engineers from as far away as London and a team of others all played a role in developing what will both be a 93-foot tall memorial and instrument, he said. Polished aluminum chimes ranging from 5- to 10-feet-long – each tuned for different notes – will ring from the tower, driven by the wind to produce a memorializing melody, he said.

“To our knowledge, tuned chimes of this size and arrangement in this magnitude are unique in the world,” Murdoch said, before ceremonially striking a single 98-pound chime that was on display for Sunday’s “Soundbreaking.”

Murdoch struck it twice – the first time, letting its C-note chime quietly echo through the air.

The second time, it was followed by a recording of all 40 wind chimes playing the type of peaceful song that White said will one day be commonplace here.

To White, it served as a rebirth of 40 voices.

“And those collective voices will echo in an infinitely changing harmony, making each (national park) visitor’s experience both unique and timeless,” said White, whose cousin, Louis Nacke II, was among the passengers who died in the Sept. 11, 2001, crash.

He was one of two family members who addressed a crowd of several hundred attendees Sunday – the other, Friends of Flight 93 Treasurer Emily Root Schenkel, whose cousin, Lorraine Bay, was a United Flight 93 flight attendant.

“As the chimes ring, I hope we all remember … the sound they make is a sound of a great nation – a nation of great character and great people,” said U.S. Department of Interior Secretary Ryan Zinke.

Construction on the nearly $6 million Tower of Voices project is expected to be underway through next summer.

A National Park Foundation grant is funding the work, which is just one piece of more than $43 million in funds the foundation has raised from more than 110,000 donors in recent years, park foundation President Will Shafroth said.

“When we come back again … close your eyes and listen to those 40 tones and voices. And when you find that one chime that resonate in your heart from that lost loved one, let it give you a sense of calming – and the peace of mind we all deserve to continue on in life,” Walker said.

Let it also serve as another reminder – that their stories will be told here “for generations to come,” he said. “To understand – and never forget.”

Hurst writes for the Johnstown, Pennsylvania, Tribune-Democrat.