Crossing drones with satellites: ESA eyes high-altitude aerial platforms / Navigation / Our Activities / ESA

High Altitude Pseudo-Satellites, or HAPS, are platforms that float or fly at high altitude like conventional aircraft but operate more like satellites – except that rather than working from space they can remain in position inside the atmosphere for weeks or even months, offering continuous coverage of the territory below.

The best working altitude is about 20 km, above the clouds and jet streams, and 10 km above commercial airliners, where wind speeds are low enough for them to hold position for long periods.continue reading http://www.esa.int/Our_Activities/Navigation/Crossing_drones_with_satellites_ESA_eyes_high-altitude_aerial_platforms/(print)