The Flight 93 National Memorial is a new 2,200-acre national park in Western Pennsylvania where United Flight 93 crashed on September 11, 2001. The designed memorial landscape commemorates the 40 heroes on Flight 93 who gave their lives thwarting a terrorist attack on the U.S. capital. The design transforms the site – a former reclaimed strip mine – to a place of environmental and symbolic healing. The memorial landscape moves visitors through a composition of open spaces defined by site walls, planting, walkways and courts, gateways and building elements. The Sacred Ground lies at the heart of the Memorial, at the edge of the Field of Honor and embraced by an allee of red maples backed by 40 Memorial Groves.

The restoration of the land and designed interventions create a unified, immersive experience attuning visitors to the hallowed ground and the qualities of the changing landscape. Commemoration and healing are at the heart of the project in form – the qualities and physical features of the site are used for their expressive power and the design’s scale corresponds to the imprint of these events on the national conscience; experience – landscape and architectural interventions engage all the senses towards reflection; and ecological function – as the former open-pit coalmine is now a vibrant meadow, wetland, emerging grove, and forest.

The visitor center is located between two ascending concrete memorial walls where the flight path crosses the edge of a large bowl-shaped field that used to be an open-pit coal mine. The siting of the visitor center emphasizes the importance of this intersection and offers different options for visitors to explore more of the site. Long tall concrete site walls conceal approaching views from parking. A walkway aligned with the flight path orients visitors to the trajectory of the plane on 9/11 and leads through tall narrow portals to an overlook of the expansive field and crash site below. From the visitor center, a walk east through the formal alle or west down a meandering path leads to the crash site and wall of inscribed names of the passengers and crew.

The plane crashed at the edge of this open field in front of a grove of hemlock trees, burning many of the trees. State law required that the crash site be restored to its original condition, so the burned trees were removed and mulched and the crash crater was filled in. This Hemlock Grove, that absorbed the inferno of the crash, is the backdrop to the crash site that is the focal point for the entire memorial experience. The distinct structure of the trees, with its straight, tall trunk and alternating angled branches, is the inspiration for the design motif expressed in concrete elements throughout the memorial, paving patterns and the aluminum ceiling and soffit at the visitor center.

The final major phase includes the Tower of Voices near the park entrance. As a unique musical feature, the tower required an equally unusual combination of consultants, including a musician, chimes artist, acoustical engineer and wind consultants, and design process. The scale and complexity of 40 chimes, and the variability of wind directions and velocities, required an interactive process of testing and simulation for determining a final design. This required musical tuning theory to establish the right tones, chime mock-ups for 3D recordings, computational fluid dynamic modeling to test tower shapes, wind tunnel testing to simulate site conditions and acoustic simulation in a sound lab to digitally test chime configurations in final tower volumes to create the full effect of all chimes together. The Tower of Voices commemorates the forty passengers and crew through a living memorial in sound to remember their ongoing voices.

Upon entering the park, visitors first see the Tower of Voices that marks the gateway to the Memorial site and symbolically introduces the memorial theme. The Tower signals the entry to and exit from the Park. Rings of White Pine trees resonate from the tower, with flowering Hawthorn and Redbud trees and additional species partially screen this area from the site entrance and Approach Road. A paved walkway and a trail from the parking area wends its way through the pine trees to a raised clearing for the tower. Future trails will originate from the Tower to lead through the park.

Architecture offices involved in the design: Paul Murdoch Architects

Project location: 6424 Lincoln Hwy, Stoystown, PA 15563, United States

Design year: 2020 / Ongoing

Year Built: 2020 / Ongoing



LILA 2023 Sponsor