The Delicate Work of Suspending a 6,800-Pound Wind Tunnel Fan

As visitors enter the National Air and Space Museum’s recently reopened Boeing Milestones of Flight Hall, an incredible collection of hanging artifacts draws their gaze upward. Throughout the hall, a unique assembly of aircraft, spacecraft, and satellites dangle like oversized holiday decorations from the ceiling and walls. Once their eyes adjust to this amazing scene, the thoughts of many visitors may turn to logistics: How exactly does the Museum suspend such large objects? What kind of plans and expertise do staff need to safely complete the work of hanging multi-ton artifacts?

To try and answer these questions, we turn our attention to the grande dame of the exhibition hall: the 36-foot wide, 6,855-pound Full Scale Wind Tunnel (FST) fan assembly that operated for nearly eight decades at the Langley Research Center in Virginia. Since NASA transferred the FST fan to the Smithsonian’s care in 2013, Museum staff have twice suspended it in the Boeing Milestones of Flight Hall: first in February 2015, and again in March 2024. By examining the most recent installation of this stately piece of aeronautical engineering equipment, we can shine a light on the surprisingly delicate process of suspending large artifacts, including the amazing people who do both the literal and figurative heavy lifting.

The task of moving and installing a large artifact like the FST fan requires close coordination between several specialized Museum teams to ensure the safety of all staff members and the artifact. As the individuals ultimately responsible for the care and interpretation of artifacts, curators consult with all parties involved in their exhibition and installation. Conversations about display usually start with the Exhibit Design team, which draws on its intimate knowledge of the Museum’s gallery spaces—their layout, capacity, and structural details—to help realize the curatorial vision for telling an artifact’s story. Once Exhibit Design has formulated a display plan, the Museum’s Preservation and Restoration team (PRU) is then tasked with generating specifications and drawings for engineering review, developing rigging plans, and fabricating components that allow an artifact to be exhibited. The work of physically moving artifacts falls on the Collections Processing Unit (CPU), the members of which maintain certifications in the use of heavy equipment. The CPU team also oversees any outside contractors brought in for a job, ensuring that they handle artifacts with an appropriate level of care through the entire installation process.

The 2024 installation of the FST fan assembly was part of the Museum’s multiyear renovation project. To accommodate these efforts, Museum staff removed all large artifacts from the Boeing Milestones of Flight Hall in late 2021. This presented the first challenge of the project: how to transport the giant wind tunnel fan to and from the Museum’s storage facility at the Steven F. Udvar-Hazy Center in Virginia. In consultation with the curator, PRU and CPU staff determined the easiest way to do this was to partially disassemble the artifact. The process began by detaching the large aluminum nose cone and standoff tube from the steel hub plate that connects all the fan’s components. Then, staff members unbolted two of the four opposing spruce fan blades—each of which weighs approximately 600 pounds—and removed them from the hub, reducing the width of the fan from an unwieldy 36-plus feet to a more manageable 6 feet. Using PRU-designed conveyance systems, members of the CPU team worked with art handling contractors to secure the nose cone, standoff tube, detached blades, and larger hub-and-blade assembly onto tractor trailers for transport. Though the movement of some “superloads” can only be done during the middle of the night with police escorts, such precautions were not required in the case of the FST fan assembly.

With the wind tunnel fan safely disassembled and stored, its responsible curator at the time, Dr. John Anderson, consulted with the Exhibit Design team and determined that resuspending the artifact on the gallery’s eastern wall remained the best way to display it and interpret its history. Because of the ongoing renovation, however, the suspension process had to adapt to several gallery updates, most notably the addition of new atrium shade structures to protect artifacts from light damage. To facilitate this, Exhibit Design staff prepared three-dimensional scans of both the fan assembly and the gallery space and reviewed them against updated structural plans of the building. The Exhibits team then prepared additional plans and drawings to ensure the massive fan assembly could be positioned correctly and safely. Exhibit Designer Hannah O’Toole summed up the work at this stage of the reinstallation process, saying her team served as “the bridge between design and technical/structural checks.”

Armed with the scans and documents prepared by Exhibit Design, attention once again turned to the PRU team, which began the highly technical work of coordinating the fan assembly’s resuspension in Milestones. With the artifact at the Udvar-Hazy Center, the PRU staff’s next task was to devise a way of attaching cables to the fan so it could eventually be hoisted back into place. To do this, PRU Specialist Tony Carp drew upon his understanding of the structural loading forces on large objects—expertise he gained integrating mechanical support equipment and satellite systems for movement through ground testing environments. For the 2024 installation, Carp was able to reuse a plate and bracket system he had designed during the fan assembly’s initial suspension a decade earlier. This PRU-fabricated apparatus allows staff to attach cables to the artifact without making alterations.  

With the connection problem resolved and the FST fan’s return to the Museum on the National Mall in March 2024, staff members faced another daunting task: safely moving the oversized object to its intended display area through what was essentially an active construction site. Because the Boeing Milestones of Flight Hall is located nearly an entire city block away from the Museum’s west end loading area, this was easier said than done. To do this, CPU Specialist Rebekah Hiett monitored the implementation of a movement plan that allowed artifact handling contractors to convey the disassembled fan components through the Museum to a staging area in the exhibition hall. With Hiett looking carefully over their shoulders, the team of contractors used telehandlers and other heavy equipment to move the components. Hiett also kept a close eye on the artifact’s spotters, each of whom could immediately cease operations if anything appeared out of balance or in danger of striking another object.

With the FST fan’s immense components once again in the exhibition hall, the final task was to reassemble everything and safely hoist the artifact back into place. Step-by-step instructions prepared during the 2015 installation allowed PRU Specialist Carp to manage the project contractors as they put the fan back together again—a process that required reassembling 32 nut-and-bolt combinations weighing 75 pounds apiece. Connected to the PRU-fabricated bracket and rigged by contractors through reinforced lifting points in the gallery ceiling structure, the hub and blades were first lifted horizontally and then rotated vertically into position. Once this assembly was in place, Carp and the contractors proceeded to rig, lift, and reattach the aluminum nose cone in midair using a scissor lift. As with earlier operations, CPU staff were on hand throughout this entire process to ensure that nothing damaged the fan assembly—this work included padding all objects, including rigging shackles, that might impact the artifact.

When all the moving, rigging, and hoisting were complete, the FST fan—a multi-ton artifact with a history as big as its enormous components—hung gingerly some 9 inches from the wall of the Boeing Milestones of Flight Hall. And thanks to the expertise of the many Museum staff who worked to suspend this one-of-a-kind object, visitors can continue to look upward and let their curiosity soar.