In the United States, Alexander Graham Bell developed a tetrahedal kite, which was tried but not developed between 1905 and up to 1907. The United States did continue experimenting with man-carrying kites throughout the First World War. Boston-based kite maker Samuel F. Perkins made a kite train that allowed an observer to be carried skyward, but the contraption was very susceptible to wind conditions. It was used for demonstrations on the homefront, but never deployed to a war zone.
However, France and Germany did use kites on several fronts. In 1909, the French War Ministry ordered a man-lifting kite, and a Charles Dollfus held a competition to determine the best type. The winged box kite system of Captain Madiot won the Contest, but Madiot was killed in an airplane accident a year later. Following the accident, the French War Ministry asked Engineering Captain Jacques-Theodore Saconney (1874-1935) to design a kite train that could be used up an altitude of 600 meters (1,800 feet). Saconney's concept included an automobile with a winch that was driven by the automoble Engine as well as a trailer. The system was accepted by the French authorities, and it was even installed on the cruiser Edgar Quinet in 1911. Exercises were conducted in 1913 under the supervision of Captain Saconney, who had become the Director of the Aerology Laboratory and Telephoto at Chalais-Meudon in 1912.
Trials on board the Edgar Quinet.
Winch car.
Vehicles of the combined kite and balloon Company.
Readying a French observation kite
In 1914 Germany designed a folding box kite system for use on the Kaiser's u-boats. The kite was launched, and the observer in a basket was subsequently hauled up using a man-powered winch. The German Imperial Armed Forces did have a number of Felddrachenwarte for meteorological purposes all over Europé, but they seem to have used unmanned kites for weather observation at altitudes between 2,000 and 5,000 meters (6,000 to 15,000 feet). The naval equivalent was called Seedrachenwarte. The Austro-Hungarian Armed Forces had similar units.
Finally, the Imperial Russian Army used the Baden-Powell kite, while the Navy had Hargrave-type kites. A Lieutenant (N) Bolshev (Bolscheff) pioneered the use of observation kites after having worked with ballooons, but Little is known of the Russian experiences with kites.
Sources:
Walter J. Boyne (Ed.). Air Warfare. An International Encyclopedia. Vol 1, A-L. Santa Barbera: Clio, 2002
https://www.theatlantic.com/technology/archive/2012/02/gonzo-death-traps-from-the-early-days-of-aviation-man-lifting-kites/253674/
https://mashable.com/2016/09/05/man-kites/#89NpkG5.dEqj
http://kitehistory.com/Miscellaneous/Warkites.htm
http://aerohistory.org/1914-1918/mission.html
http://cerf.volant.historic.free.fr/pages/cervolantistes/saconney/la%20biographie%20saconney%20-%20Copie.pdf
drachen.org