These guys are set up in Leucate, FR, no shortage of wind throughout the year there. They say it was invented in 1995 on their website. It sounds like they use this in their kiting school? A big hazard with tethered manlifting is uneven kite pull and stalling resulting in the guy being dropped or pulled earthward fast. The pendulum tether seems to deal with part of the problem outside of wind extremes. I wonder what injuries they have had over the years, if any?
Tethered manlifting conventionally approached, has killed and badly injured a number of folks in recent times around the world. Many have been talked about on this forum. Usually they tie off to a stationary object and then get locked out, the kite stalls and slams them to death against the ground. I understand a guy in South Africa did this tying off the a park bench which broke. He was flown into the side of a high rise building.
There is a lot of history to this practice going back over a 1000 years.
"The first records of man-lifting kites come from China. The (636) Book of Sui records that the tyrant Gao Yang, Emperor Wenxuan of Northern Qi (r. 550-559), executed prisoners by making them fly with bird-shaped kite wings (see ornithopter). For his Buddhist initiation ritual at the capital Ye, the emperor parodied the Buddhist ceremonial fangsheng 放生 "releasing caged animals (usually birds and fish)".
On one occasion the emperor visited the Tower of the Golden Phoenix to receive Buddhist ordination. He caused many prisoners condemned to death to be brought forward, had them harnessed with great bamboo mats [quchu 籧篨] as wings, and ordered them to fly down to the ground (from the top of the tower). This was called a 'liberation of living creatures'. All the prisoners died, but the emperor contemplated the spectacle with enjoyment and much laughter. The (1044) Zizhi Tongjian records that in 559, all the condemned kite test pilots died except for Eastern Wei prince Yuan Huangtou.
Gao Yang made Yuan Huangtou [Yuan Huang-Thou] and other prisoners take off from the Tower of the Phoenix attached to paper (kites in the form of) owls. Yuan Huangtou was the only one who succeeded in flying as far as the Purple Way, and there he came to earth.
The Purple Way (紫陌) road was 2.5 kilometers from the approximately 33-meter Golden Phoenix Tower (金凰台). These early manned kite flights presumably "required manhandling on the ground with considerable skill, and with the intention of keeping the kites flying as long and as far as possible."
In a story about the Japanese thief Ishikawa Goemon (1558–1594), he used a man-lifting kite to allow him to steal the golden scales from a pair of ornamental fish images which were mounted on the top of Nagoya Castle. His men manoeuvered him into the air on a trapeze attached to the tail of a giant kite. He flew to the rooftop where he stole the scales, and was then lowered and escaped. In the 17th century, Japanese architect Kawamura Zuiken used kites to lift his workmen during construction. George Po****, who invented a kite-drawn buggy in 1822, had previously used kites as a method of lifting men to inaccessible cliff tops, but it was not until around the 1880s that there was serious interest in developing man-lifting kites." http://en.wikipedia.org/wiki/Man-lifting_kite