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  Remotely Piloted Vehicles (RPVs) have been around
for a long time. They started out in about the 1930s when remote control was beginning
to be reliable enough to trust an expensive airborne platform with its equipment. Most
early RPVs were target practice drones, but by World War II, top secret programs were
using them as decoys and for flying reconnaissance into dangerous areas. The craft were
large, heavy, noisy, and cumbersome. It took special piloting skills to fly because automation
was minimal or non-existent.
 Fast forward about 40 years and we started to
see vehicles like the Sparrow
being test flown. The September 1973 edition of American Aircraft modeler did a feature
article on it. At the time, such airplanes were considered larger than most modelers
could afford, and payloads like cameras were still for the adventurous. Special construction
techniques were devised for such serious airplanes. Today, of course, the is a plethora
of even ARF planes available at a relatively reasonable cost. The engines pack more power
per cubic inch of displacement, the radios are infinitely more reliable, and structural
materials now regularly include carbon fiber for strength. What will tomorrow bring?
By the beginning of the 21st century, unmanned aircraft have become so commonplace
in the military that officer flight school graduates were no longer required to pilot
many of the UAVs. The larger, multi-million dollar systems like the Predator and Reaper
drone still have officer pilots, but there are hundreds of smaller UAS packages that
are routinely carried in backpacks and employed by enlisted men on the front line. Most
take the form of a fixed-wing aircraft, but helicopters are making a big entrance now
for instances where the ability to dwell over a target for some time is needed.
One of the biggest difficulties for Unmanned Aircraft Systems is retrieval. It is
usually simple enough to launch an aircraft either by hand or from a catapult device,
but getting them back on the ground safely can be a real challenge. A number of systems
have been implemented in lieu of a wheels landing, including catching by hand for the
smallest craft, to flying the UAVs into a net for medium size ones.
The ScanEagle, developed by
Boeing and Insitu is a newer type of aerial recovery system that is much more
easily deployed than something like a net. It simply hangs a rope vertically and the
airplane flies into it so that a hook on the end of the wing snags it. A bungee cord
is used with the rope to cushion the impact. A GPS device mounted on the rope assembly
steers the ScanEagle right into itself. Pretty neat, eh? The video below shows the system
in operation. More American / European ingenuity at work!
The
Smithsonian magazine had a short write-up on the ScanEagle
retrieval system.
Posted June 25, 2011
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