Google's Loon balloons fly at 65,000 feet, about twice as high as commercial aircraft, so they shouldn't pose a hazard to aviation except during their launch and descent. At those times, Google is required to warn local aviators that it will be conducting a balloon launch.
So far this year, six advisories for high-altitude balloon launches have been issued in the area, according to data from Bravo Airspace, an aviation data and analytics company that keeps records of such notifications. All are very similar.
The most recent was on April 7 and described the planned launch of a high-altitude balloon from the airport at Winnemucca, Nevada, close to the northwest corner of the area in which Google is conducting tests. The balloon would travel in a southeasterly direction, according to the advisory, taking it directly across the test area.
A local official confirmed that Google was running Loon experiments from the Winnemucca airport, but declined to comment further, citing a confidentiality agreement between the city of Winnemucca and Google.
Google did not reply to requests for comment on the Nevada tests.
Sign up for CIO Asia eNewsletters.