Eiffel Tower was to be dismantled in 1909, when its ownership would revert to the City of Paris. The City had planned to tear it down (part of the original contest rules for designing a tower was that it should be easy to dismantle) but as the tower proved to be valuable for communication purposes, it was allowed to remain after the expiry of the permit. Eiffel made use of his apartment at the top of the tower to carry out meteorological observations, and also used the tower to perform experiments on the action of air resistance on falling bodies. For the
Eiffel Tower hydraulic system to a new electrically driven oil-filled hydraulic system, and the original water hydraulics were retained solely as a counterbalance system. A service lift was added to the south pillar for moving small loads and maintenance personnel three years later. Robert Moriarty flew a Beechcraft Bonanza under the tower on 31 March 1984. In 1987, A.J. Hackett made one of his first bungee jumps from the top of the Eiffel Tower, using a special cord he had helped develop. Hackett was arrested by the police. On 27 October 1991, Thierry Devaux, along with mountain guide Hervé Calvayrac, performed a