E-Mail IMAGE: The drone-delivery service in Christiansburg, Va. -- the first in the country to deliver goods directly to residences on demand -- gave researchers a unique opportunity to study how people... view more Credit: Virginia Tech The week of Thanksgiving last year, a postcard arrived in mailboxes in Christiansburg. A link to a survey was on the back. On the front, there was a picture that was, by then, very familiar to the residents of a town that made history in 2019 as the first place in the U.S. to have a residential drone delivery service: a yellow-winged drone with a small cardboard box tucked underneath it.