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My local engineering newspaper has an article on the X-37B craft, with an image displaying the craft within half of the shell that encapsulates it. The shell has a number of plates arranged on its inside surface, which look decidedly like silvery 'Lego' base plates:
What are those plates for?
The image is captioned:
This is how the X-37B is encapsulated at the top of an Atlas 5 rocket from the Cape Canaveral Cape Canaveral launch site in Florida. Photo: U.S. Air Force courtesy photo Photo: U.S. Air Force courtesy photo.