Making the Most of Treating a 30-Foot Diameter Umbrella-Shaped Antenna | National Air and Space Museum

2022-10-28 01:51:12 By : Mr. Yong Lang

"I Didn’t Invent the Rainy Day, I Just Own the Best Umbrella"

The conservation and restoration teams at the Museum’s Steven F. Udvar Hazy Center are currently treating objects related to the renovation of our Washington, DC, location. One of these objects appeared like an oversized umbrella in the Mary Baker Engen Restoration Hanger, where its complex size and shape required ingenuity from the Museum’s Collections Department in order to devise a treatment plan. 868mhz Pcb Antenna

Making the Most of Treating a 30-Foot Diameter Umbrella-Shaped Antenna | National Air and Space Museum

This 30-foot parabolic antenna is part of a full-scale engineering model of the Applications Technology Satellite-6 (ATS-6). ATS-6 was launched by NASA in 1974 to test new technologies in space communication and became the world’s first satellite to provide educational television programming across the United States and rural parts of India, thanks to the Satellite Instructional Television Experiment. The artifact in our collection is a Thermal Structural Model used during the development of the satellite to analyze the design for the effects of launch vibration and the extreme temperatures of space.

Applications Technology Satellite-6 (ATS-6) during testing at the Johnson Space Center. (Image courtesy of NASA)

The ATS-6 was in storage at the Museum’s Paul E. Garber Facility for almost 30 years because the entire artifact, spanning over 28 feet high, 52 feet wide along the solar array, and 30 feet in diameter across the antenna, was simply too big to display. Until now! Renovation of the Museum on the National Mall has allowed for the umbrella-shaped parabolic antenna reflector to be integrated into the new One World Connected gallery, where it is suspended from the ceiling. As with all objects that are scheduled for display, the antenna required a thorough examination before receiving any necessary conservation treatment. Conservation and restoration team specialists worked together with the curator to carefully plan the treatment steps that would accommodate the size and complexity of this object.

The antenna was brought into the restoration hanger in its stowed, doughnut-shaped position, attached by the central structural hub to the top of a 10-foot-tall storage mount. No one knew quite what to expect when removing the straps and allowing the 48 aluminum ribs and copper-coated Dacron (polyester) mesh of the canopy to unfurl into the deployed position. The antenna was designed to be constrained in a tightly wound configuration, with the ribs under a great deal of pressure, so that it would spring open when deployed in space. It took a group of six Collections Department staff holding onto the ribs to control this springing action when it was opened inside the restoration shop. Once the antenna was unfurled, the unusual size and shape made it difficult to work on or even examine, and it became apparent that specialized equipment would be needed. None of the standard ladders or aerial work platforms could provide access to the entirety of the artifact. This dilemma gave the Collections Department the opportunity to utilize its wide range of skills to create a new way to make treatment possible.

Conservator Rachel Greenberg and restoration specialist Duane Decker using the moveable ladder, platform, and storage mount to access the Kapton foil on the top of the ATS-6 antenna. (Smithsonian Institution)

Conservator Rachel Greenberg using a movable ladder and platform to clean the ATS-6 Antenna. (Smithsonian Institution)

Welder Kenny Mills fashioned a wheeled ladder that could attach at the top to the storage mount through the artifact’s support hub. This ladder arched a few inches over the canopy and could be rolled around the entire circumference of the object. A moveable platform was added to the arched portion of the ladder that would allow someone to hover over the antenna canopy. Conservator Rachel Greenberg and restoration specialist Duane Decker were able to take turns using the platform to clean the object with a backpack HEPA filtered vacuum while the other person rolled the ladder around the circumference. Additional cleaning of the copper-coated Dacron mesh was completed with polyurethane sponges and cleaning of the painted aluminum ribs with deionized water. Each gore-shaped mesh section was broken up into three smaller parts by moving the platform from top to bottom, resulting in a very time-consuming process. Only after the antenna was cleaned could a more thorough assessment be made and treatment be performed, such as corrosion reduction, repairs to the aluminum ribs, and mending of the Kapton.

Members of the Collections Department helping to refurl the ATS-6 antenna for storage. (Smithsonian Institution)

Once the ATS-6 antenna was treated, it had to be placed in storage until the construction of the new gallery was complete and the object could be installed for display. This meant wrapping the 30-foot-diameter canopy back into a doughnut shape on top of the storage mount. This is where teamwork really came into play! Approximately 25 Collections staff helped to slowly walk the ribs in a circular direction to compress the antenna canopy in and up around the mount while others spotted and led communication. Just as before it was unfurled, the ribs were being put under a great deal of tension and required the strength of the Collections staff to hold it in place while straps were tied around them. The antenna was then covered with plastic sheeting for protection while in storage. It has since been unfurled and installed in its new home in the One World Connected gallery, now on display.

The 30-foot diameter parabolic ATS-6 Antenna after treatment and prepared for storage. (Smithsonian Institution)

Without the skills, expertise, and teamwork of the staff in the Collections Department, the treatment of such an unusual artifact could not have been achieved. 

Making the Most of Treating a 30-Foot Diameter Umbrella-Shaped Antenna | National Air and Space Museum

Rf Male Connector We rely on the generous support of donors, sponsors, members, and other benefactors to share the history and impact of aviation and spaceflight, educate the public, and inspire future generations.  With your help, we can continue to preserve and safeguard the world’s most comprehensive collection of artifacts representing the great achievements of flight and space exploration.