Tracing the crash path of Flight 93 in a Pennsylvania field, a dramatic new national memorial makes us pause and remember the heroism of the passengers who selflessly fought against terrorism.
By Sue McCraven
Each of us has an indelible memory of where we were that Tuesday morning when we first heard the news of passenger jets crashing into New York’s Twin Towers and the Pentagon. I was in a small basement office across the street from a cemetery when the radio broadcast caused me to stand still with shock and disbelief. Most of us needed more than one viewing of televised videos of the Manhattan skyline before we could comprehend the unbelievable: Our homeland had suffered a large-scale terrorist attack.
Later came the news of passengers on United Airlines Flight 93 using cell phones to call loved ones to say their flight from Newark to San Francisco was highjacked. The passengers tried to regain control of the aircraft, causing the Boeing 757 to crash into a Shanksville, Pa., field, just 150 miles northwest of Washington, D.C. All 40 passengers and crew plus the four highjackers were killed on impact. Flight recorders revealed that the heroism of the passengers who fought back prevented the plane from reaching its probable target, the U.S. Capitol, just a 20-minute flight from the crash site.
The Flight 93 Memorial
The U.S. Army Corps of Engineers (USACE), Pittsburgh District, was hired by the National Park Service, project owner and site manager, to provide construction management services for a memorial commemorating the heroism of the passengers and crew. After two years of construction, the Flight 93 Memorial was completed and dedicated in September 2011.
As visitors travel along the custom pavement that traces the gouged path of the plane as it plowed into the earth, they come to the names of those who perished, elegantly etched into white Vermont marble. This inspiring memorial, designed by Paul Murdoch Architects of Beverly Hills, Calif., impels visitors to reflect on the last moments of life for the men and women aboard Flight 93 as the pilotless plane plummeted, upside-down, out of the blue sky on that terrible morning.
Sara Hillegas, P.E., a hydraulic engineer with the USACE, Pittsburgh District, one of two construction management representatives on the project, explained some of the details of the memorial’s precast concrete elements. “The precast architectural concrete, cast by Royal Stone of Williamston, Mich., was trucked in 20-ft sections to the project site, and crane-lifted into place by a crew of three to four workers to form the Memorial Wall and base for the Memorial Walkway benches. The architectural precast contains black granite aggregate, black sand, is stained black and sealed to give it a matte finish. The concrete work on site took tremendous coordination and scheduling between multiple subcontractors and suppliers.”
The Flight 93 Memorial gives rise to the legendary acts of a few brave Americans who thwarted the hijackers’ mission and prevented the certain deaths for many others had the plane reached its intended target.
Sue McCraven, NPCA technical consultant and Precast Solutions editor, is a civil and environmental engineer.