All the business of war, and indeed all the business of life, is to endeavor to find out what you don't know by what you do; that's what I called 'guessing what was at the other side of the hill.'
Duke of Wellington
The Israeli Sky Sapience Hovermast 100 makes so much sense you would have to wonder why no one thought of it before. Actually they did via fixed extendable masts from vehicles—or if you go back much earlier—from balloons. And soldiers have been climbing trees, or otherwise been after the high ground, as long as we have been bashing each other’s brains out—and aerial reconnaissance has been around for some time for the obvious reason that the higher you are, the more you can see.
However, the Hovermast is in a league of its own. It is simple, fast, and relatively inexpensive. Let me quote from defense-update.com
The Hovermast 100 tethered observation system developed by the Israeli company Sky Sapience has completed development in 2013 and already entered operational service with the Israel Defense Forces (IDF). Sky Sapience has recently demonstrated the naval applications of its new Hovermast 100, during a demonstration for a foreign customer the system was deployed at sea, demonstrating effective border control, observation and surveillance missions in both land and maritime environments.
Hovermast operates as a fully autonomous system, using a combination of two counter-rotating rotors and four stabilizing rotors managing lift, attitude, height and orientation. The system can operate from vehicles, vessels on the move or fixed positions. Self contained in a compact container weighing about 300 kg, the system can be installed on standard tactical vehicles, pick-up trucks, armored vehicles, as well as unmanned ground or naval platforms or small vessels. Powered through the tether, the Hovermast 100 can carry a payload weighing six kilograms (13.2 pounds).
The platform can be lifted within seconds to an altitude of 50 meters (164 ft) above ground providing 360⁰ over-the-hill vision, it is ideal for surveillance and observation missions. It can operate at relatively high wind velocity of up to 25 knots. Unlike mast mounted payloads that must be flushed to vertical position, the tethered sensor can also deploy form a slope of up to 20 degrees. In addition to transferring power the tether is also conducting wide-band data transfer from the payload to the ground, eliminating electromagnetic emissions that could be monitored or jammed. The system has already been supplied to the IDF and selected by several international customers.
The standard payload selected for the Hovermast 100 is the T-STAMP from Controp, at a weight of only 2.8 kg, this stabilized payload comprises either a cooled 3-5 micron IR Camera with x 6 optical zoom Lens or an uncooled 8-12 micron Camera with x4 optical zoom. In addition, T-STAMP carries a CCD Day TV Camera with x 10 optical Zoom and a laser pointer. The platform can also be configured to carry additional payloads, including radars, lasers designators, hyprospectral sensors, communications relays, SIGINT and cellular antennas. The system is made of advanced composite materials, is impermeable to water and dust, and operates in adverse weather conditions.