"The Supreme Court addressed whether an observation made from a low-flying helicopter constituted a search in Florida v. Riley,58 a plurality concluding that it did not. At issue was the use of a police helicopter, hovering at 400 feet (an altitude prohibited for fixed-wing aircraft), to observe, through an opening in a greenhouse roof, marijuana growing inside. The plurality read [California v.] Ciraolo as establishing that so long as there was no breach of the Federal Aviation Agency (FAA) safety regulations, the property owner had no legitimate reason to expect privacy with respect to non-intimate activities undertaken in the curtilage of his home that were plainly visible from above. Five justices would have preferred to consider how often members of the public actually make low-altitude helicopter flights over populated areas in determining whether the claimed expectation of privacy was reasonable. The plurality suggested that surveillance overflights that comply with FAA regulations might nevertheless constitute searches if they were to involve “undue noise,  wind, dust, or threat of injury” or to reveal “intimate details connected with the use of the home or curtilage.”9"
Best, Richard A., Jr.; Elsea, Jennifer K., "Satellite Surveillance: Domestic Issues," Congressional Research Service (Washington, DC: Library of Congress, January 13, 2011), p. 15.